Author Archives: Frank Schäfer

Pristobrycon careospinus ( = Serrasalmus careospinus)

6. February 2026

In 1992, W. L. Fink and A. Machado-Allison described two piranha species of the genus Pristobrycon from locations in the Rio Atabapo basin (Venezuela): P. careospinus and P. maculipinnis. The two species differ in color. While P. maculipinnis has small dots on its body and spots on its vertical fins, the fins of P. careospinus are unmarked and the spots on its body are large. Unfortunately, the scientists only had a few specimens at their disposal. They had six specimens of P. maculipinnis and only one of P. careospinus. This is naturally problematic given the well-known color variability of piranhas and the equally notorious color changes these fish undergo during their growth (scientifically known as ontogenetic color change). 

 

In 2006, piranhas from Venezuela with very impressive colors appeared on the ornamental fish market for the first time. At that time, they were identified as Pristobrycon maculipinnis, and it was considered likely that P. maculipinnis and P. careospinus were the same species.

We have finally succeeded in importing these beautiful piranhas again, this time four specimens. We now consider the Pristobrycon imported in 2006 and those recently reintroduced to belong to the species P. careospinus and believe that the earlier assumption that P. careospinus and P. maculipinnis were identical was incorrect.

The difference between Pristobrycon and other piranha genera is not visible externally. It is a bone feature, namely the palate (referred to in scientific publications as the palatine or ectopterygoid). This is toothed in typical Serrasalmus species, smooth and toothless in Pygocentrus species, and rough and toothless in Pristobrycon species. Recent molecular biological studies no longer classify P. careospinus in the genus Pristobrycon, but rather in Serrasalmus. The species may therefore be called Serrasalmus careospinus.

Virtually nothing is known about the behavior of this species. In nature, it apparently occurs mostly singly. In aquariums, piranhas are often notorious fin biters, which can make it necessary to keep them singly. On the other hand, Oliver Lucanus (verbal communication) kept a group of the beautiful species we are presenting here, under the name of P. maculipinnis, together for at least a while. Overall, representatives of the genus Pristobrycon (in the conventional sense) are only very rarely kept in aquariums, which is a pity, as all species usually remain under 20 cm in total length and some are very attractively colored. Detailed care reports are lacking in the aquarium literature, not to mention breeding reports. 

The pictures show specimens from the 2006 import and a collage of the four animals that have just arrived in our fishhouse, which naturally still need to recover from the stresses of transport, but are obviously in perfect health.

For our customers: the animals have code 283285 on our stock list. Please note that we only supply wholesale.

Text: Frank Schäfer, photos: Frank Schäfer & Erwin Schraml

Hyphessobrycon amapaensis

6. February 2026

The three-banded flag tetra, Hyphessobrycon heterorhabdus, was once one of the most sought-after small tetras. When tetras were very fashionable – in the 1950s to 1970s – this species was classified as a “problem fish” because it did not reproduce without tricks and gimmicks. However, keeping this species without breeding intentions was completely problem-free. Today, we know of a whole complex of three-banded flag tetra species, and identifying them is anything but easy. It is likely that the animals kept at that time were not H. heterorhabdus at all. More information on this can be found here: https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hyphessobrycon-heterorhabdus-2/

However, a very closely related species of this three-banded flag tetra is fairly easy to identify: Hyphessobrycon amapaensis, the Amapa three-banded flag tetra. This species was caught and brought back from Brazil during an ornamental fish expedition by Bitter and Hessfeld, which was still legally possible at the time (1997). A year later, it was scientifically described as a new species by Zarske and Gery. It was found in a savanna stream on the B156 in the state of Amapa. The water there was clear, slightly brownish, slightly acidic (pH 5.8 to 6.3), very soft (both KH and GH below 1° dH, conductivity 9-13 µS/cm) and around 25-27°C warm. The most interesting accompanying fish was Hyphessobrycon takasei (https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hyphessobrycon-takasei-2/).

The distinguishing feature of Hyphessobrycon amapaensis is the black section of the longitudinal stripe. In all three-striped flag tetras in the narrower sense, the longitudinal stripe consists of three differently colored, parallel stripes: one red, one light, and one black. In contrast to all other three-banded flag tetras, the black band of Hyphessobrycon amapaensis is greatly widened immediately behind the gill cover to the end of the pectoral fins and also extends into the caudal fin. The uppermost band is coral red and much clearer than in other three-banded flag tetras. To identify the species with certainty, you need to take your time. Depending on its mood, each fish can strongly contract the body cells that contain the black pigment – then the fish becomes light in color and the black markings almost invisible – or expand them. This is what makes the very rapid color change that so many fish exhibit possible. When Hyphessobrycon amapaensis is frightened, the black longitudinal band is often not easily recognizable.

Hyphessobrycon amapaensis is the only species of all three-banded flag tetras to have gained a firm place in the hobby. It is available in good quality as offspring in various sizes almost all year round, although its breeding still requires an experienced tetra breeder even today. Wild-caught specimens only come onto the market very sporadically. The pictures show captive-bred specimens in the md-lg size class. It is an ideal fish for well-maintained community aquariums. Soft, slightly acidic water is favorable for optimal coloration, but the fish are highly adaptable and practically any tap water is suitable for their care. The species is completely peaceful towards conspecifics and non-conspecific fish, and should be kept in a school. The maximum length is about 4 cm. They eat any commercially available ornamental fish food of a suitable size.

For our customers: depending on size and origin, the animals have the codes 259452 (breeding sm-md), 259453 (breeding md-lg), 259454 (breeding lg), 259463 (wild lg), and 259464 (wild xlg) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Danio frankei

6. February 2026

We often find that the fish species that are most commonly found in stores are not yet posted on our website. This is, of course, because there are always so many new and exciting species to introduce, but admittedly, even the supposedly old ones still have a lot to offer! 

Danio frankei appeared on the ornamental fish market in 1962, seemingly out of nowhere, and was described as a new species by Hermann Meinken based on aquarium specimens. Since then, there has been intense (and ultimately inconclusive) speculation in aquaristic and scientific literature to this day as to whether D. frankei is merely a mutation of D. rerio, the zebrafish, or whether it is a separate species. Only two things are certain: Firstly, D. rerio and D. frankei can easily be crossed, and the hybrids are fully fertile. Second: Danio frankei has never been found in the wild. Neither of these facts says anything about the species status of D. frankei. With many livebearing toothcarps, it is possible to breed hybrids, and here too there is no restriction on fertility. Nevertheless, no one would seriously doubt that platies and swordtails are different species. And for many other species, their natural origin remained unknown for decades. Famous examples include the Odessa barb (Pethia padamya) and the black paradise fish (Macropodus spechti). The aquarium rosy barb (Pethia conchonius), whose appearance has been very well documented since it was first imported in 1903, is also still unknown in the wild. Wild-caught rosy barbs from Bengal (from where the species was described) look completely different. If Danio frankei is a naturally occurring species, its occurrence can be assumed to be in northeastern India, an area where many regions remain inaccessible to this day.

Although Danio frankei (leopard danio) and D. rerio (zebra danio) have been crossed so often that purebred animals are now virtually extinct in the breeder´s farms, the phenotype* of the leopard danio has remained unchanged to this day – more than 70 years since its arrival in the hobby. There are breeding forms – golden, veil-finned, genetically modified (glowfish), etc. – but the original type still exists. It differs from the zebrafish not only in that it has spots instead of longitudinal stripes on its body (the genes responsible for this have been identified, by the way), but also in its intense golden body color. Very small, 5 mm long leopard danios look like golden neon tetras. A zebra danio never has this coloration. Until proven otherwise, it should therefore be assumed that B. frankei is a valid species.

Leopard danios are a pure joy in the aquarium. They are completely undemanding, absolutely peaceful schooling fish that are happy in any drinking water habitat and will eat any standard ornamental fish food of a suitable size. The water temperature can be between 16 and 30°C; keeping them in permanently warm water shortens their life expectancy, while keeping them in permanently cool water causes their colors to fade. It is therefore best to allow the fish to follow a certain seasonal rhythm, such as that found in the subtropics of India – the original home of the Zebra danio and probably also the leopard danio.

For our customers: Danio frankei has – depending on size – code 407602 (md) to 407604 (xlg) in the wild form, 407611 (sm) to 407615 (sh) as veiltail, 407623 (md-lg) as gold form, 407634 (lg-xlg) and 407635 (sh) as veil-tailed gold form on our stock list. Please note that we only supply wholesale customers.

*In biology, phenotype refers to external appearance, regardless of genetic identity. The opposite of this is referred to as genotype.

Text & photos: Frank Schäfer

Andinoacara rivulatus “Silverseam”

6. February 2026

Until relatively recently, the magnificent large-growing Andinoacara species were classified in the genus Aequidens. The genus Andinoacara comprises a total of eight recognized species. Three large-growing species—A. blombergi, A. rivulatus, and A. stalsbergi—form a species complex. These three species can therefore be relatively easily confused with one another. The easiest way to tell them apart is with the gold-edged variant of A. rivulatus (see https://www.aquariumglaser.de/en/25-perchlike-fishes/andinoacara-rivulatus-2/), as only this form has yellow-orange fin edges within the complex. A. stalsbergi has silver-white fin edges and is therefore also known as the “silverseam cichlid.” This is misleading in that it is not the decisive difference between the species, as both other species can also have silver-white seams. Instead, you have to look at the scales to identify them. In A. stalsbergi, the center of the scales is light (bright green-blue when alive), and the edges of the scales are dark. In the other two species, it is exactly the opposite. The caudal fin seam of the male A. rivulatus of the silverseam variant is significantly wider than in the other two species. This makes this form easy to recognize. 

Andinoacara rivulatus is relatively widespread along the Pacific slope of Peru and Ecuador. So it is not surprising that the species has developed different color variations. We have the “silverseam variant” of A. rivulatus as German offspring in stock. The “goldseam variant,” on the other hand, is mainly offered by Asian breeders.

All three Andinoacara species mentioned can grow to well over 20 cm in size, meaning they can become real giants. Keeping them in aquariums that are too small is a problem, as they then become “green terrors,” as they are known in English. Any tank mates will then have nothing to laugh about. In sufficiently large aquariums, however, they are rather calm large cichlids. Sexual maturity sets in much earlier, at around 8 cm in length. Andinoacara are open breeders with a parental family. They are undemanding in terms of water composition; any drinking water is suitable for care and breeding. They eat any standard ornamental fish food of a suitable size. The water temperature can be between 20 and 26°C, or slightly warmer for breeding. During brood preparation, these fish become active in interior tank design. It is therefore best to plant their aquarium with large, potted plants that will not suffer too much from the fish’s activity. The sexes can be distinguished quite easily by the seam of the tail fin, which is much narrower in females. But the old rule of cichlid care also applies here: while dominant males are always easy to recognize (in this case: broad tail fin seam and forehead hump), oppressed males like to camouflage themselves as females in terms of color and physique. So if you want to breed, you should purchase a group of younger fish, from which harmonious pairs will usually form naturally.

For our customers: the animals have codes 610012 (4-6 cm), 610013 (6-8 cm), and 610014 (10-12 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Brochis sp. aff. evelynae ( = Corydoras sp. aff. evelynae)

30. January 2026

In aquarium science, there are always fish that are shrouded in legend. One of these is definitely Hoplisoma evelynae, which was described as early as 1963 based on a single specimen collected by Axelrod in the upper Rio Solimoes region (the name given to the Amazon above its confluence with the Rio Negro). For some unknown reason, this species rarely finds its way into the hands of ornamental fish catchers. Over time, a real hype developed around this animal, which essentially looks like a skunk cory (Hoplisoma granti, commonly known in the hobby as Corydoras arcuatus) with an interrupted dorsal line, two parallel stripes across the flanks, and a striped caudal fin.

We have now been able to import a small number of armored catfish with exactly this pattern, but with the head shape of a Brochis of Clade 4 (the pointed-headed armored catfish) from Colombia. We had seen pictures of this species before, which originates from the Amazon region in Colombia and is shipped via Leticia. But we had not been able to import them until now. As far as we know, this fish has not yet been assigned a C or CW number (C98 and CW13 are similar, but in our opinion represent different species). Round-snouted animals – i.e. Hoplisoma – with very similar coloring have been assigned the C number 90. C90 differs from the “real” H. evelynae in that it has a prominent black saddle patch directly at the base of the dorsal fin.

Our fish are about 6 cm in total length and are probably sexually mature, but not yet fully grown. A photo of a show-size fish at Armando Ortega-Lara (2016) shows even more clearly than our specimens the special head shape that is so typical of Brochis of clade 4.

For our customers: the animals have code 229573 on our stock list. Please note that we only supply wholesale.

Literature:

Ortega-Lara, A. (2016): Guía visual de los principales peces ornamentales continentales de Colombia. SERIE RECURSOS PESQUEROS DE COLOMBIA – AUNAP. Santiago de Cali, Colombia.

Text & photos: Frank Schäfer

Sewellia patella

30. January 2026

Members of the Sewellia genus are also commonly referred to as “splendid hillstream loaches” because their markings are often very contrasting. However, there are also species with plain coloring, such as the most recently scientifically described species, S. pudens Kottelat, 2025. A total of 15 Sewellia species have been named, but it is difficult to say how many of these are valid due to the sometimes very poor quality of some of the descriptions.

There is no doubt, however, about the validity of Sewellia patella. The species is known to date from the basins of the Ba (Da Rang) River and the Sesan River, both in central Vietnam (Gia Lia and Kon Tum provinces). This species is quite similar at first glance to the well-known S. lineolata (https://www.aquariumglaser.de/en/fisharchive/sewellia-lineolata-2/,  all relevant care and breeding information can also be found there), but is clearly distinguished by its coloration. S. lineolata, S. marmorata, and S. pterolineata, all of which could be confused with S. patella at a glance, have a black band along the outside of the pectoral fins, which is completely absent in S. patella.

You can be absolutely sure when you look at the animals from below. As the only “confirmed” Sewellia species (S. analis, one of the questionable species, is also said to exhibit this characteristic), S. patella has two semicircular appendages on its anal fin, the purpose or function of which is unknown. However, they are probably related to reproduction or the behavior of the sexes towards each other, as these appendages are shaped differently in males and females. Another sexual difference is the presence of lobe-like appendages on the surface of the pelvic fins, which are difficult to see in living animals. These appendages are larger in males than in females.

In their original description, the authors Freyhof and Serov also provide valuable information about the natural habitat. According to their observations, S. patella prefers faster-flowing waters than, for example, S. lineolata. The flow velocity in the habitat of S. patella was between 0.6 and more than 1 m/s. This should at least be taken into account when acclimatizing the animals. Otherwise, based on our experience to date, everything that should be considered when caring for S. lineolata also applies. As the species is currently only known to occur in a small area and populations there are in sharp decline, it is considered endangered. It is therefore desirable to establish a stable aquarium population from captive-bred specimens. The maximum length of S. patella documented to date is 49 mm (standard length without tail fin).

For our customers: the animals have code 455113 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Ctenopoma acutirostre

30. January 2026

One of the most beautiful African labyrinth fish is the leopard bush fish, Ctenopoma acutirostre, which grows to a length of around 15-20 cm. It is native to the Congo and is usually collected from Stanley Pool for aquariums. There they live during the day under the floating meadows of water hyacinths (Eichhornia crassipes). Occasionally, however, imports also come from the central Congo region (Lac Mai Ndombe) or from Cameroon. The species is apparently widespread throughout the Congo basin. At dusk, they go out hunting. They drift through the water like dead fish, imitating a decaying fish carcass with their spotted pattern. This attracts small fish that want to feed on carrion and now serve as food for the leopard bush fish.

When it comes to breeding, the leopard bush fish has proven to be inaccessible in private hands. Although the animals are completely peaceful among themselves, and it is easy to distinguish between the sexes (sexually mature males have spines behind their eyes and on their flanks, which serve to hold the female during mating). Nevertheless, breeding in aquariums has so far only occurred by chance, with deliberate breeding attempts failing. It should certainly be taken into account that these fish are mainly active at night, mating also takes place at night, and the eggs have usually already been eaten as a tasty treat by the morning, but this only partially explains the failure of aquarists to breed them so far.

In Southeast Asia, however, the systematic breeding of these beautiful fish has been successful for years, and so we are able to offer adorable leopard babies on a regular basis. Like their parents, they have already mastered the innate hunting technique of playing dead. Fortunately, however, fish are not needed for their diet. Both young and adult leopard bush fish are easy to accustom to frozen food (mosquito larvae, etc.) and, once acclimated, also enjoy eating granules and other dry foods. 

C. acutirostre are completely peaceful towards fish that are about half the length of themselves and therefore no longer suitable as food, so they can also be kept well in community aquariums. However, the community should not consist of hectic fish, as leopard bush fish like it quiet and dim.

There are hardly two leopard bush fish with exactly the same pattern. However, the offspring all have the familiar leopard pattern. In wild-caught fish, on the other hand, the most unusual color variations occur, from completely monochrome brown to vertical stripes. In the past, this has led to confusion with Ctenopoma ocellatum, which also originates from the Congo. Another phenomenon that has only been observed in wild-caught fish so far is the occurrence of unusual body colors, such as orange or (very rarely) even purple. However, these colors disappear over time in the aquarium and after a few months at the latest, these fish look like almost all other C. acutirostre: beige body color with chocolate-colored spots. Leopard bush fish are long-lived; 10-15 years in the aquarium is completely normal, and anecdotally, there have been reports of animals twice that age.

There is not much to say about care. The water values are completely irrelevant; any drinking water is suitable for care. The water temperature can be between 22 and 30°C. Everything has already been said about feeding and socialization, as well as about tank setup. Just keep in mind that labyrinth fish can catch a cold when they come to the water surface to breathe. So in winter, when you ventilate, make sure that the air space above the aquarium does not cool down too much. But this applies to all labyrinth fish.

For our customers: depending on their size, the offspring have codes 115011 (3 cm) to 115015 (6-8 cm), and the wild-caught fish have codes 115001 (3-4 cm) to 115005 (14-16 cm). Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Geophagus cf. camopiensis „Araguari“

30. January 2026

The Brazilian state of Amapá is located in the far northeast of Brazil on the Atlantic Ocean. It is particularly interesting from a zoogeographical point of view because its rivers – such as the large Rio Araguari river system – are home to fish species that are otherwise only found in neighboring French Guiana in the Rio Oyapock. Due to the high price level in French Guiana, ornamental fish exports from there are hardly possible: the animals are simply too expensive.

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We are therefore delighted to be able to offer at least two of the coveted Oyapock fish species from Brazilian Amapá populations (Rio Araguari basin): Retroculus septentrionalis (perhaps more on this later, once the animals have settled in better and their colors have become more attractive) and Geophagus cf. camopiensis. 

Geophagus experts, with whom we are in constant correspondence, are fairly certain that this is Geophagus camopiensis, a species that was described as early as 1903 by Pellegrin from the Rio Camopi, a northern tributary of the Rio Oyapock in French Guiana. Collections made by aquarists in French Guiana have made it possible for us to know what this species looks like. A very large flank spot is particularly striking. The Amapá Geophagus that we were able to import were sent under the erroneous identification “Geophagus proximus.” The exporter was apparently misled by the large flank spot of adult animals. G. proximus is known to be the Geophagus species with the largest flank spot of all. In the Amapá population of G. cf. camopiensis, the flank spot is slightly smaller and often (not always!) very rectangular. Since it cannot be completely ruled out that our fish are an extremely similar but different species, we write the species name with cf. (which means “compare with”). We assume that Geophagus cf. camopiensis “Araguari” is identical to G. sp. “Araguari,” which was first imported in 1988.

Incidentally, there is at least one other Geopagus species in Amapá, which we were able to import for the first time in 2013. This was undoubtedly a form from the G. altifrons group with a very small flank spot. 

Geophagus cf. camopiensis “Araguari” is a colorful, hardy eartheater. The water temperature should be kept on the higher side (26-28°C, 30-32°C for breeding), but otherwise the fish are highly adaptable. They are openspawners, but the young are incubated in the mouth after hatching. Both parents participate in broodcaring. In technical terms, they are biparental, larvophilic mouthbrooders. The maximum length of these fish is 18-20 cm. In nature, they are often found in groups, similar to other Geophagus species. They are therefore comparatively peaceful large cichlids, although it must always be borne in mind that the behavior of cichlids is strongly influenced by the size and layout of the tank. As with all Geophagus species, a large area with sand for chewing is essential in the long term. A few larger, flat stones should be provided for spawning.

Many thanks to Andreas Jekel for the discussion and the pictures of adult animals!

For our customers: the animals have code 675322 (6-8 cm) and 675323 (8-10 cm) on our stock list. Please note that we only supply wholesale.

Text: Frank Schäfer, photos: Frank Schäfer & Andreas Jekel

Parailia pellucida

30. January 2026

The African glass catfish, Parailia pellucida, is a magnificent aquarium fish, but strangely enough, it is virtually unknown among hobbyists. Yet this species is almost always available. We import it regularly from Nigeria. 

The African glass catfish is not closely related to the Asian glass catfish (most commonly found in aquariums: Kryptopterus vitreolus, see https://www.aquariumglaser.de/en/10-catfishes/kryptopterus-vitreolus-2/). The latter belongs to the true catfish family (Siluridae), making it a cousin of the wels catfish, while African glass catfish belong to the Schilbeidae family. The similar appearance and behavior of both groups of glass catfish is therefore not based on kinship, but on similar living conditions, just as with bats and birds, which are also not closely related simply because they both have wings.

Externally, P. pellucida differs from Kryptopterus in that it has an adipose fin and eight long barbels (Kryptopterus has two). The maximum length of the African glass catfish is around 15 cm, but specimens over 8 cm in length are extremely rare. The genus Parailia comprises five species, but only P. pellucida is regularly available in the trade, with P. congica (from the Congo, otherwise very similar to P. pellucida) occasionally appearing. P. pellucida is extremely common in nature. The species is an important link in the food chain for larger fish species, but is also consumed directly (in the form of soup or sauce) due to its often massive occurrence. The large schools usually comprise animals of very different sizes, often mixed with other species (e.g., Pareutropius buffei). Here, too, small P. buffei are often found as bycatch in imports.

African glass catfish are completely peaceful plankton eaters that should always be kept in groups with their own kind. These fish love well-planted aquariums with plenty of cover and lighting that is not too bright, and they are easy to feed with all standard foods. African glass catfish are completely undemanding in terms of water hardness and pH value; any drinking water is suitable for keeping these catfish. In contrast to their better-known Asian cousins, African glass catfish are always clearly visible in the aquarium during the day, at least if the aquarium is not too brightly lit. The Asian species, on the other hand, prefer to stay hidden and wait for dusk.

The animals have probably never been bred intentionally; the males often turn very dark during courtship and regularly court in the aquarium. There is a report from 1977 according to which eight young animals suddenly appeared in the aquarium without any special intervention, initially staying in the root area of Java fern (Micropterus). So, if necessary, it would probably not be a serious problem to breed these fish for aquariums. However, there is currently no need for this, and for ecological reasons, sustainable wild capture (as is absolutely the case here) is preferable.

For our customers: the animals have code 155904 on our stock list. Please note that we only supply wholesale.

Text & photos: Frank Schäfer

Betta macrostoma

23. January 2026

Betta macrostoma is undoubtedly one of the most beautiful fighting fish—and one of the most sensitive. There is hardly any other fish species that is as susceptible to bacterial infections as this one. Many breeders have no choice but to run their tanks continuously through UV filters. A little tip: clay dissolved in the water also reliably “captures” bacteria.

We do not normally stock these precious fish, only occasionally offering a few pairs. However, we currently have a number of immature fish measuring 5-6 cm in length on offer; the maximum achievable size is around 8 cm. At a size of 5-6 cm, it is not yet possible to distinguish between the sexes with certainty, but these immature fish are considerably more adaptable to changing conditions. Usually, females at this age have more contrasting banding and a more delicate head profile. However, when the fish are caught and their colors fade depending on the situation, such subtle characteristics are usually not noticeable.Sexually mature males are easily recognized by a dark spot on their dorsal fin, which is always absent in females.

There are a few points to consider when caring for Betta macrostoma. First, they are excellent jumpers. In nature (the species is endemic to Borneo, where it is found in the Sultanate of Brunei), they live in small streams and often have to overcome small waterfalls. In addition, flying insects are an important part of their diet. The bettas jump well and aim precisely for this food. Due to their sensitivity to bacteria, the water should be humic acid (pH 5.5-6), which is best achieved in soft water; in such water, denitrification often works poorly, so it is essential to keep an eye on the nitrite level! Most harmful bacteria do not like the acidic pH value (unfortunately, this also applies to beneficial filter bacteria), the fish would not mind otherwise. Worm food (Tubifex, etc.) is taboo for B. macrostoma. It leads to intestinal diseases. Instead, the food should be rich in fiber. Insects and crustaceans are ideal food, and the animals also accept dry food, but this should not be their sole source of nutrition. 

The water temperature can be between 24 and 28°C. Even if the fish do not necessarily need it, dense planting with fast-growing aquatic plants is highly desirable. They maintain the water quality at a high level because they release bactericidal substances into the water and also process most of the ammonium excreted by the fish. This compensates to a certain extent for the often weak biological filter performance in acidic water.

For our customers: depending on their size, the animals have codes 384000 (sm) to 384004 (6-8 cm) on our stock list. Please note that we only supply wholesale customers. 

Text & photos: Frank Schäfer

Giuris margaritacea (G. aporocephalus)

23. January 2026

When one sees these sleeper gobies from the Indo-West Pacific region, where they are very common, for the first time, one spontaneously thinks of an oversized Australian spotted goby (Mogurnda). The main difference between Giuris and Mogurnda is – aquaristically speaking – that the tiny larvae of Giuris develop in the sea, while the much larger ones of Mogurnda develop in freshwater. 

In literature, Giuris margaritacea is described as a euryhaline fish that can live equally well in fresh, brackish or salt water. But at least the colourful population from Indonesia, which we have just been able to import, is probably a freshwater fish.

The extremely wide distribution of the species from the East African coast, the Indonesian islands, the Philippines, the western Australian coast and along the coast of Southeast Asia stands in strange contradiction to the rarity of these really magnificent fish in the hobby. G. margaritacea even seems to be a quite compatible animal. At least in the photo basin the couple (the female can be recognized by the clearly smaller and shorter first dorsal fin; the colour differences are rather mood-related) got along very well. By the way, aquarium observations indicate that this up to 40 cm long goby feeds mainly on insects and is not a fish-eater like the marble goby (Oxyeleotris marmorata). Nevertheless, one should be careful with community fish, all fish that fit into the mouth are endangered.

We could now import some 15-20 cm long, quite splendid specimens of this goby, which is also called Ophieleotris aporos (Manila goby) in the older aquarium literature.

ADDENDUM: In a revision of the Giuris species (Keith, P. and M. I. Mennesson (2020): Review of Giuris (Teleostei: Eleotridae) from Indo-Pacific islands, with description of three new species. Cybium v. 44 (no. 4): 331-349), the species G. aporocephalus (Macleay, 1884), which for decades was considered a synonym of G. margaritacea, was declared valid again. The animals we offer as G. margaritacea therefore belong to the species G. aporocephalus. Apart from the name, everything stated above applies to both species.

For our customers: the animals have code 418124 on our stocklist. Please note that we only supply wholesalers.

Text & photos: Frank Schäfer

Dimidiochromis compressiceps

23. January 2026

The Malawi eyebiter Dimidiochromis compressiceps (formerly: Haplochromis c.) is one of the most unusual cichlid species in Lake Malawi. It is a predatory fish, with males reaching up to 25 cm in length and females up to 20 cm. In 1966, the species was mistakenly considered to be a specialized eye eater. However, this behavior has never been observed in the lake. There, these fish, which grow to a length of about 4 cm, feed mainly on smaller fish, which they swallow whole. The predator’s extremely compressed body makes it almost invisible when it stands among Vallisneria plants with its head tilted slightly downward. Unlike most other predatory fish, Dimidiochromis compressiceps can target its prey with both eyes at the same time due to its narrow head profile.

Dimidiochromis compressiceps is found almost throughout the entire lake and also occurs in the outflow of Lake Malawi, the Shire River, and its lake-like extension, Lake Malombe. The animals look the same everywhere, except for those found near Chizumulu Island in Lake Malawi, which have a yellowish base color instead of the usual silver.

Predatory fish are usually not very territorial and relatively peaceful towards conspecifics and other fish that are not considered food. D. compressiceps is no exception. Usually, only one male in a group of these cichlids will turn blue and establish a breeding territory. Such a breeding territory consists of a sand pit, which is preferably created in the preferred habitat, i.e., Vallisneria stands. Vallisneria are—just as a reminder—underwater plants with long and narrow, ribbon-shaped leaves that form large underwater meadows in suitable habitats all over the world. Females from the surrounding area that are ready to spawn come to this nest. After spawning, as is usual with Haplochromis relatives, the males leave the females alone to care for the mouthbrood. Non-breeding males look like females in color and are treated as such by breeding males. The species reaches sexual maturity at a length of around 8 cm (males) and 6 cm (females). Once sexual maturity has been reached, the sexes can be distinguished quite reliably by the shape of the anal fin, which is significantly larger in males and also has egg spots. Males grow faster than females, so in a group of animals of the same age, the larger ones are usually the males.

Care and breeding are easy in an aquarium. However, the aquarium should not be too small, given the possible final size. Do not choose hectic cichlids (Mbunas) as companions, but rather other calm Haplochromis relatives, such as Nimbochromis, Cyrtocara, and the like. The pH value should not fall below 7.5 on a permanent basis, which is easier to achieve in harder water. The water temperature can be between 24 and 28°C. They will eat any standard ornamental fish food, including flake food, but nutritious bites (e.g., cichlid sticks, rich frozen food, etc.) should form the main part of their diet. For the setup, plant a Vallisneria meadow, and the substrate should be at least partially sand. Stones or roots should only be used very sparingly.

For our customers: depending on their size, the animals have codes 520230 (3 cm) to 320235 (11-12 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Megalechis thoracata (formerly: Hoplosternum thoracatum)

23. January 2026

The Port Hoplo Megalechis thoracata – maybe the synonym (now invalid) name Hoplosternum thoracatum is more familar to some readers – is one of the earliest aquarium fish at all. The fish has only one real disadvantage: the maximum size, which is about 15 cm (or sometimes even larger). However, the species has a comparatively small mouth and so it fits quite well in a community tank with more robust and somewhat larger fish. Megalechis have a great fan community who calls them the „fighting sausages“.

Breeding Megalechis is very interesting, for male Port Hoplos build up a foam nest, similar to that known from anabantoids. Megalechis prefers to build it under a swimming item (breeders often use the covers of old coffee boxes, but this is hardly ever available in the wild). The male is very pugnacious while guarding the nest and will even jump in the keeper´s face if this curious person comes too close to the nest!

We have from time to time offspring of a particularly pretty, very contrasty variant in stock. Despite their small size – 5-6 cm – the animals are already sexually differentiated (sexually ripe males have greatly enlarged pectoral fin spines and the bone plates covering the breast are much larger than the corresponding bone plates of the females) and in the females you can see the orange spawn shimmering through the belly sides.

For our customers: the animals have – depending on size – code 259301 (2-3 cm) to 259306 (11-13 cm) on our stocklist. Please note that we only supply wholesale.

Text & photos: Frank Schäfer

Inpaichthys luizae

16. January 2026

A pretty new tetra is Inpaichthys luizae, a species that was only formally described in January 2025. It occurs in areas that are hardly accessible to scientists and commercial fishermen because they are privately owned. What is known, however, is that these locations are tributaries of the Rio dos Peixes in Brazil, which in turn is a tributary of the Rio Juruena. The entire area belongs to the Rio Tapajós basin.

This fish first became known in the hobby at the end of 2023. At that time, it was referred to as Inpaichthys sp. “Black Arrow”. As with many new species, only a few specimens initially came onto the market at comparatively high prices; low three-digit euro amounts per specimen were demanded. However, it quickly became apparent that this species is just as productive and easy to breed as its well-known cousin Inpaichthys kerri, the royal tetra. At present (January 2026), the fish are still not cheap, but they are not unaffordable either. We source them as offspring from East Asia.

The sexes of these cute animals, which according to scientific descriptions reach a standard length of about 4 cm (i.e., without the tail fin), are quite easy to distinguish due to the stronger red coloration of the fins in males. This color is already clearly visible in adolescent animals. It can be assumed that aquarium specimens grow 1-2 cm larger than wild-caught fish, a phenomenon that can be attributed to the much better food supply for aquarium fish and, of course, the considerably higher age that fish in aquariums reach compared to wild specimens.

So far, the animals have proven to be absolutely typical small tetras, which do not differ from the royal tetra, Inpaichthys kerri, in terms of aquarium requirements. A very interesting phenomenon with I. luizae is the fact that most specimens have an adipose fin, but some do not. The absence of an adipose fin is very unusual in tetras; at the time, the presence of an adipose fin was one of the reasons for establishing the genus Inpaichthys, as otherwise it is very similar to the genus Nematobrycon (emperor tetras). All Nematobrycon species, without exception, lack the adipose fin. However, there are also specimens of I. luizae without adipose fins, but they are in the minority.

For our customers: the animals have code 264792 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Neolamprologus callipterus

16. January 2026

The snail cichlids of Lake Tanganyika continue to enjoy unbroken popularity. Their comical breeding behavior, in which they guard their spawn and young in empty snail shells, never ceases to fascinate. It is particularly interesting to observe an entire colony of these fish inhabiting what is essentially a snail shell city. In most snail cichlids, males and females are similarly small, allowing both to crawl into the snail shell.

This is not the case with Neolamprologus callipterus. Here, the males grow to a total length of 15 cm, three times the size of the females. Even very large snail shells (in the photo session we used an empty shell of the Asian Pila ampullacea, seehttps://www.aquariumglaser.de/en/31-crayfishes-shrimps-crabs-snails-mussels/pila-ampullacea-3/, with a diameter of around 6 cm) can no longer be actively occupied by fully grown males of N. callipterus. Younger animals – in the picture, the males are around 8 cm long and the females 4-5 cm – still do so, but such large snail shells do not exist in nature.

There, the males of N. callipterus gather empty snail shells to build large residential complexes. Only males with as many snail shells as possible have a chance of attracting females to move in with them. To fertilize the eggs laid inside the snail shells, the male must bring his rear end as close as possible to the mouth of the snail shell, where he releases his milk. The sperm enters the interior of the shell through the movements of the female and fertilizes the spawn there.

N. callipterus is easy to care for. Tap water is perfectly suitable in most areas. The pH value should not fall below 7.5 on a permanent basis. The water temperature can be between 24-28°C. They eat any standard ornamental fish food, although the large males also like to eat larger chunks. Roman snail shells are suitable as snail houses and can be purchased for little money in delicatessens. The best viewing opportunities are provided by a large aquarium with a sandy bottom. Scatter 20-30 snail shells in it. Now you can watch the male build his “snail shell city.”

For our customers: depending on their size, the animals have codes 543201 (2-3 cm) to 543203 (6-8 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Sturisoma nigrirostrum

16. January 2026

The genera Sturisoma (15 scientifically described and accepted species, east of the Andes = cis-Andean) and Sturisomatichthys (13 scientifically described and accepted species, west of the Andes = trans-Andean) are referred to in German as Störwelse (= sturgeon catfish), in English as Royal Farlowellas.

Sturisoma nigrirostrum from Peru is imported more or less regularly. The species is easily recognizable by the jet-black underside of its “beak,” a feature that also led to its scientific name. The type locality of the species is Contamana, Río Ucayali, Peru. Another similar species, also with a black rostrum underside from Peru, is the species Sturisoma graffini from the Madre de Dios region, which was only newly described in 2018. For various reasons, fish from this region are considerably more expensive than those from the Ucayali, so S. graffini is rarely found in the ornamental fish trade.

For unknown reasons, some of the Sturisoma nigrirostrum imports have an upward-curving rostrum. Ingo Seidel (personal communication) caught both forms—those with a normal nose and those with a hooked nose—together at the same location in Peru. This is a quirk of nature whose purpose is completely unclear. 

Caring for Sturisoma and Sturisomatichthys does not usually pose any major difficulties. Any tap water suitable for drinking is suitable for this purpose. These relatively large fish (20-25 cm) appreciate current and clean water, which is why powerful filtration must be provided and regular, generous partial water changes are mandatory. They eat all the usual foods for ornamental fish, with food tablets and similar forms being particularly suitable. In addition, plant-based food must always be offered (vegetable slices, crushed frozen peas, lettuce, dandelion leaves, etc.). The water temperature can be between 24 and 28°C.

As far as has been attempted to date, all Sturisoma species can be bred in aquariums. In any case, they spawn readily. As open breeders, they often spawn on the front glass of the aquarium, where the male, recognizable by a “sideburn” of odontodes that grows during the breeding season, looks after the eggs. It is usually quite easy to get the young fish to hatch, and rearing them is not difficult for the first one to two weeks. However, many breeders then experience massive losses. Those who succeed in rearing the young fish keep their methods a closely guarded secret, so that the cause of failure among those who do not succeed is still not entirely clear.

For our customers: the animals have code 294853 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Hoplisoma sp. C3 ( = Corydoras sp. C3)

16. January 2026

Hoplisoma sp. C3 (previously classified in the collective genus Corydoras) is a very beautiful armored catfish, especially adolescent specimens, because they often develop high dorsal fins at this age. However, this is a temporary phenomenon that can sometimes also be observed in Hoplisoma metae. Only fully adult males of C3 – the animals grow to a length of approximately 5-6 cm – develop such long fins again. H. sp. C3 are imported from Colombia and Venezuela and originate from the Rio Meta basin. They are shipped either as “Corydoras deckeri” or as “C. bondi.” Deliveries of “Corydoras bondi” (which is a different species found only in the Guiana countries) or “Corydoras deckeri” (which is a fantasy name that sounds scientific but is not scientific) are always a surprise. Sometimes they are Hoplisoma axelrodi, sometimes H. loxozonus, and sometimes the scientifically undescribed species C3.

All three species mentioned are very diverse. It therefore seems questionable whether they are actually three different species (apart from the coloration of typical specimens, there are no known differences) or perhaps rather a species swarm of occasionally hybridizing forms that do not quite fit into our concept of “species.”

C3 is typically colored like Hoplisoma loxozonus, but the black horizontal band runs down the middle of the body like in H. axelrodi, not along the back like in H. loxozonus. However, some of the color variants of C3 look so completely different that one might think they were different species, were it not for the fact that all these color variants are connected by intermediate stages. It is quite interesting that usually about 80%–90% of such Hoplisoma imports correspond in color to one of the three main forms mentioned (i.e., H. axelrodi, H. loxozonus, and H. sp. C3), and the rest are variants that differ significantly. What does not occur, or hardly ever occurs, is that the other two species are found among H. axelrodi, for example, or H. axelrodi as bycatch with the other species. This suggests that the three main forms normally occur spatially separated from each other in nature. 

Apart from the problematic identification or species delimitation, C3 is an easy-to-care-for armored catfish that has no special requirements and is also easy to breed. When breeding, it is advisable to select the males based on the shape of their pelvic fins (larger and pointed in males, smaller and rounded in females). The long dorsal fin membranes are only present in some animals, not all.

For our customers: depending on their size, the animals have codes 223601 (small) to 223604 (medium-large) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Polycentropsis abbreviata

16. January 2026

Polycentropsis abbreviata means roughly translated “short and similar to Polycentrus”. In fact the African Leaffish looks very similar to Polycentrus schomburgkii from South America. Both species witness the existence of the ancient super continent Gondwana. Gondwana was formed from what is now South America, Africa, India, Australia, and Antarctica. South America drifted away from Gondwana about 100 million years ago. The ancestor of the small leaffishes – both species, the African as well as the South American become only about 8 cm long – must have existed already at that time and most probably it looked very much alike the recent species. The P. abbreviata that still exists today comes from West Africa, from Benin to Gabon. We import it from Nigeria.

Polycentropsis abbreviata is known as the “African Leaffish”. The camouflage as a dead leaf is really astonishing. So the fish drifts around and preys on small fish and shrimps, which are caught with the very large evertable mouth. The ability to change coloration is amazing. The very same specimen can change within seconds from marbled to light beige or even almost black. Even very small leaffishes can do that. Specimens measuring 1-2 cm in length have a different, very contrasting black and white pattern. This coloration is also found in various labyrinth fish in very young stages, such as Ctenopoma weeksii, Sphaerichthys osphromenoides, and Ctenops nobilis. The purpose of this coloration has not yet been researched.

The broodcare of the African Leaffish is also remarkable. The male builds a kind of bubble nest under a broad leaf of a plant. This is similar to the bubblenest of the anabantoid fish, but the peculiar bubbles are larger. Here the fish spawn. The male alone takes care for eggs and newly hatched larvae. The broodcare ends when the youngsters swim free. Sadly the sexes can be only hardly told apart. Females tend to stay a bit smaller and have a smaller head.

The African Leaffish is only very rarely offered. The species needs to be fed with live food items like White Moskito larvae, large Daphnia, small earthworms, Tubifex and small feeder fish. Anyone who is able and willing to fulfill this demand will find the African Leaffish a fascinating study subject.

For our customers: the fish have code 162004 on our stocklist. Please note that we exclusively supply the wholesale trade.

Text & photos: Frank Schäfer

Discus wild Oriximiná

9. January 2026

Oriximiná is located on the Rio Trombetas in the Brazilian state of Pará. From there we receive fantastic blue discus in magnificent colors. For the tiresome question of species classification in discus, see here: https://www.aquariumglaser.de/en/fisharchive/the-scientific-species-name-of-discus-cichlids-an-open-question/

Blue discus are generally very variable in color (“polychromatic”), even those from the same location. That is why the “Oriximina Super Color,” “Oriximina Royal Blue,” “Oriximina Red,” and “Oriximina Cross” are all members of the same population, sorted more or less according to certain color characteristics. 

We currently have beautiful Oriximiná discus in stock again. The pictures show a small selection of these fish from the “Super Color” selection; the photos were taken recently for this post and are not archive images. Unfortunately, just when the annual discus season (the actual discus season begins around October and ends in April) should be in full swing, there are major delivery problems from Brazil. This time, it has nothing to do with climate change, environmental pollution, or overexploitation, but is due to human inadequacies. Of course, ornamental fish exports from Brazil – as everywhere else in the world – are subject to strict controls and regulations. This is fine and ensures the sustainability of this ecologically sensible, environmentally friendly extractivism. However, if a key position is filled by the wrong person, this can have far-reaching consequences. That is why, unfortunately, relatively few wild-caught discus from Brazil are currently available.

For our customers: the “Oriximina Super Color” fish shown have code 731065 (12-15 cm) on our stock list; the code numbers for other sizes start at 731064 (8-12 cm) and end at 731066 (14-17 cm, see https://www.aquariumglaser.de/en/25-perchlike-fishes/25e-perchlike-fishes-5-remaining-cichlids-from-south-and-central-america/wonderful_large_discus_from_oriximina_arrived__en/). Please note that we only supply wholesale customers. Only available in limited quantities!

Text & photos: Frank Schäfer

Melanotaenia nigrans

9. January 2026

In 1982, Gerald R. Allen and Norbert J. Cross published the first modern comprehensive overview of the rainbowfish known at that time. By that time, Allen had already described 12 new species since 1978. When he began systematically studying rainbowfish, only 19 Melanotaenia species had been described between 1843 and 1978, a period of 135 years. In 1982, 8 species were known from Australia, 14 from southern New Guinea, and 5 from northern New Guinea, for a total of 27 species. Today, 89 species are generally accepted! That is a tripling of the number of species in less than 45 years, and there is no end in sight. Almost every expedition to New Guinea still brings back new forms. The very first species ever described was Melanotaenia nigrans, which was described as Atherina nigrans in 1843. If you look at older aquarium literature up to the early 1980s, you will read that M. nigrans was imported in 1927 as the very first Australian ornamental fish species. 

Given the figures listed above, it should come as no surprise that this identification of the fish at the time was incorrect. In reality, it was the similar species M. duboulayi. The first genuine imports of M. nigrans did not take place until around 1976. Melanotaenia nigrans comes from northern Australia, where it is irregularly distributed: from the Kimberley region in Western Australia through the northern part of the Northern Territory to the Cape York Peninsula in northern Queensland, including a number of offshore islands such as Groote Eylandt in the Gulf of Carpentaria and some islands in the Torres Strait. There are persistent rumors that the species also occurs in New Guinea, but it has never been scientifically proven there. Since there are no exports from Australia, all animals in the trade are captive-bred specimens. The species is said to be naturalized in the Philippines.

This slender rainbowfish usually grows to around 7 cm in length, but older aquarium specimens can reach lengths of around 12 cm. Like so many rainbowfish, this species is also very variable in color. Its slender body shape and unusually strong shoaling behavior make it a beautiful contrast to other rainbowfish species. In nature, the species occurs together with M. trifasciata, M. australis, and M. inornata.

M. nigrans has no special requirements in terms of water parameters and nutrition. In nature, it is found in relatively soft water (maximum 135 µS/cm) with pH values between 5 and 8 and temperatures between 19 and 35°C. It is therefore generally highly adaptable, but this should not tempt you to expose the animals to sudden changes in their environment. They cannot tolerate this at all! In our experience, the species is not entirely insensitive and is more suitable for advanced enthusiasts.

For our customers: the animals have code 428352 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Schistura pridii

9. January 2026

We have received a very small number of one of the smallest and definitely one of the prettiest loaches in Thailand: Schistura pridii. These cute black and white dwarfs grow to only 3-4.5 cm in length. As far as known, this species, which was only scientifically described in 2003, only occurs in shallow, fast-flowing forest streams 30-100 cm deep with stony, gravelly bottoms in the upper Mae Teng River basin in Chiang Mai Province.

Due to its limited range, only a few specimens are caught each year so as not to endanger the population. Fortunately, a large part of the known occurrences are located in a nature reserve (the Doi Chiang Dao Wildlife Sanctuary). For dedicated aquarists, breeding these cute fish is a wonderful challenge. We are not aware of any breeding reports, but it can be assumed that breeding is similar to that of hillstream loches (Sewellia). 

The water in its natural habitat has a high current speed, is cool (64-75°F), relatively hard, and slightly alkaline. The substrate should consist of gravel that is not too fine in order to accommodate the high current speed; hollow, slightly larger stones serve as resting and hiding places. The species is not picky about food. Sexual differences are only slight and consist mainly in the slightly larger body size of the female. The animals are sociable and fairly peaceful, apart from small, harmless scuffles. From the above, it is clear that Schistura pridii should be kept by experienced keepers with breeding ambitions.

For our customers: the fish have code 454982 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Brienomyrus brachyistius

9. January 2026

We received a species of mormyrid from Nigeria that we had not seen for years: Brienomyrus brachyistius. This comparatively small species, with a maximum length of 17.5 cm, but usually remaining significantly smaller at 10-12 cm, is a close relative of the comparatively frequently imported species B. niger (see https://www.aquariumglaser.de/en/03-bony-tongues/brienomyrus_niger_en-2/).

These playful, intelligent fish are very lively and are less noticeable for their coloration than for their unusual, amusing behavior. All mormyrids belong to the weakly electric fish species. They have an electric organ in their tail stalk; it is so weak that the electrical discharges cannot be felt. They use this to scan their surroundings, similar to bats using ultrasound, but also to communicate with other members of their species. In fact, mormyrids have developed a type of “language” that is almost unique in the animal kingdom (only New World knifefish do something similar). This language is species-specific. Using special electrodes that record electrical discharges and convert them into a graphic image (similar to an ECG), it is possible in Africa (mormyrids are an exclusively African family with currently (2025) 22 genera and 236 species) to identify the species present in a body of water without dipping a net into the water. New species have even been discovered in this way!

Among our animals, there are some larger, slimmer fish that we believe to be males, and some stockier-looking animals that are probably females. Nothing is known about the reproductive biology of these mormyrids. In the aquarium, the animals readily eat any type of live, frozen, or dry food that fits in their mouths. The chemical composition of the water is irrelevant for their care, and the water temperature can be between 22 and 28°C. The fish are peaceful towards other species and do not damage plants. They are mainly crepuscular, so you should provide plenty of hiding places and dense vegetation to give them cover during the day.

For our customers: the fish have code 103502 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Nannostomus rubrocaudatus

9. January 2026

In 2002, a deep red dwarf pencil fish from Peru was imported under the names Nannostomus marginatus “Purple” or N. marginatus “Red.” Axel Zarske from the Senckenberg Natural History Collections Dresden, Museum of Zoology formally described this species in 2009 as Nannostomus rubrocaudatus. We had imported the type specimens on which the scientific description is based from Peru.

At first glance, the new species resembles the already known N. mortenthaleri (see https://www.aquariumglaser.de/en/fisharchive/nannostomus-mortenthaleri-2/), but can still be easily distinguished from this species. N. mortenthaleri, for example, always has a white belly. Further species characteristics are listed in the scientific description. The scientific first description is available as a free download at https://www.senckenberg.de/wp-content/uploads/2019/08/02_vertebrate_zoology_59-1_zarske.pdf.

Nannostomus rubrocaudatus does not exhibit very distinct sexual differences. The intensity of the red coloration varies greatly depending on mood. However, females never turn as red as males. What is particularly tricky is that males low in the hierarchy can fade significantly and camouflage themselves as females in terms of color; females can only be reliably identified by their differently shaped anal fins.

The maximum size of this species is around 3-3.5 cm. It is easy to care for, but should not be kept in small aquariums, as the males fight their rivals quite fiercely and the weaker specimen needs space to escape. If this is not available, damage may occur.

The natural range is in Peru, Dep. Loreto. Here, the species is collected for export near the village of Saramirisa on the Maranon (the upper Amazon) between the tributaries Rio Morona and Rio Santiago. The relatively high price of the fish is explained by the fact that the animals live among dense branches in the wild and have to be laboriously picked out individually. Mass catches, as with other Nannostomus species, where thousands of specimens can easily be caught with a net, are not possible with N. rubrocaudatus.

For our customers: Nannostomus rubrocaudatus has – depending on size – code 272261 (sm) to 272265 (lg-xlg) for wild-caught specimens and 272272 for captive-bred specimens on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Xiphophorus hellerii „Black Tiger“

19. December 2025

Breeding marbled swordtails on a red background is a challenge. With the “Black Tiger,” it has succeeded. Each “Black Tiger” has its own unique body markings. Until now, these swordtails have almost exclusively been offered with a whitish body color (in which case they are referred to as marble). Many of the black scales have a blue sheen (known as “mirror” in breeding circles), which shines and sparkles magnificently when light hits it from the side. The black coloration of these swordtails increases with age. These are beautiful animals, which were first supplied to us (in 2019) by a German breeder; we now obtain them from Sri Lanka. 

In view of the current weather disaster in Sri Lanka, we hope that the breeding farms have not suffered too much damage. In Sri Lanka, many families earn an indispensable additional income by raising the young fry delivered by the breeding farms into saleable fish in specially constructed ponds behind their houses. This extensive breeding method ensures that the fish are particularly healthy. Unfortunately, this form of ornamental fish rearing is also particularly susceptible to freak weather conditions. Some platy and guppy varieties have already been lost. However, we can still offer a good number of “Black Tiger” swordtails. Asking specifically for livebearers from Sri Lanka now will greatly help the families affected!

For our customers: the animals have code 420409 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Danio tinwini

19. December 2025

Aquarium Glaser has once again received the smallest known Danio species, which is closely related to the zebrafish (Danio rerio), from Burma. Danio tinwini was first imported in 2005, at that time still known as Danio sp. “Panther.” The species, which was scientifically described in 2009, grows to only about 2-3 cm in length and is ideal as a schooling fish for smaller aquariums. 

As mentioned, these fish are native to Burma. They are found in the state of Kachin, in the far north, in the border region with China. They are therefore subtropical fish that should not be kept in permanently warm conditions, otherwise they become susceptible to disease. 

This results in a temperature range of 15-27°C, depending on the season. The water values are otherwise irrelevant (any drinking water is suitable for care and breeding), and they eat any standard ornamental fish food of a suitable size. Danio tinwini is completely peaceful and does not damage plants.

For our customers: The species has the code number 413692. Please note that we only supply wholesale customers.

Text & photos. Frank Schäfer

Hoplisoma coppenamense (formerly: Corydoras coppenamensis)

19. December 2025

On the Guiana Shield of South America – a very old geological formation that covers large parts of Venezuela, Guyana, French Guiana, Suriname, and parts of Brazil and Colombia – there is a group of small, closely related species of armored catfish that look so similar that they were sometimes considered synonymous with each other: Hoplisoma bondi, H. coppenamense, and H. sipaliwini.

Probably the most attractive of the three is H. coppenamense, which was originally (in 1970) described as a subspecies of H. bondi, which was described from Venezuela. Most ichthyologists today no longer follow the somewhat vague concept of subspecies. They argue that either a fish is clearly recognizable in terms of its identity, in which case it is a species, or it is not, in which case there is no need for a subspecies name. This is a somewhat simplified representation, but it gets to the heart of the matter. After all, as far as we know, there are no hybrids (so-called intergrades) between H. bondi and H. coppenamense in the wild. Therefore, the division into two species is probably justified.

However, there is little difference in color between the two species. The markings of H. coppenamense are clearer and less blurred; the spots on the head are particularly prominent (only indistinct in H. bondi). In addition, H. coppenamense is slightly more elongated and has a rounder head than H. bondi. H. sipaliwini looks very similar to H. coppenamense, but has a dark stripe that runs diagonally forward from the base of the dorsal fin to the gill cover (see https://www.aquariumglaser.de/en/10-catfishes/corydoras-sipaliwini-2/). It is quite important to know the differences, because there have been no commercial exports from the Guyana countries for many years, and even C. bondi from Venezuela was last in stock in 2009. We are therefore dependent on aquarium breeding, and it is essential that these are kept pure.

The care of all three species is simple and typical for armored catfish. These 4.5 to 5 cm long animals have no special requirements in terms of water or nutrition. Breeding is also quite successful, but not particularly productive. Since only hobby breeders are involved in breeding these animals, they will probably remain a top rarity on the ornamental fish market for the foreseeable future.

For our customers: the offspring of H. coppenamense that we currently have available for sale have code 226302 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer & Erwin Schraml

Yasuhikotakia modesta

19. December 2025

We received from Thailand this wonderful sport of the Blue Loach (Yasuhikotakia modesta, formerly known as Botia modesta). The species is well known for its variability.

Most often the fish are blue with bright red fins (see https://www.aquariumglaser.de/en/07-carp-like-fishes-1-loaches/yasuhikotakia-modesta-2-3/, there you will also find lots more information about the species.), but the body colour can vary from blue over green to blue-grey and the fins can be anything from yellow over orange to deep red, all depending on the population. The tiger pattern a phenomenon that cannot be explained currenty, It appears from time to time, most often in younger specimens (this is the reason why it is often explained as a juvenile pattern), but it can also appear in adult fish.

For our customers: the fish have code 404002 on our stocklist. Please note that we exclusively supply the wholesale trade.

Text & photos: Frank Schäfer

Garra sp. Sunset-Goldscale

15. December 2025

The genus Garra is incredibly diverse and confusing. Currently (December 2025), 277 species names are associated with Garra, of which 171 are generally considered valid. The distribution area is huge and extends across parts of Africa and large parts of Asia; they can be found basically anywhere where it does not get too cold in winter. In the last comprehensive revision of Asian species from 1964, Menon distinguished only 37 species! In Africa, the genus is represented by at least 24 species. In Asia, its distribution ranges from Turkey (Garra caudomaculata, G. culiciphaga, G. kemali, G. klatti, G. menderescensis, G. orontesi, G. rezai, G. rufa, G. turcica, G. variabilis) across the Arabian Peninsula, Iran, and Iraq, and over the Himalayas to the east into the tropics. Caves and oases are also colonized. The genus is particularly species-rich in mountainous regions. From the above, it is clear that the genus Garra is currently very confusing.

We have once again received a magnificent Garra species from India (more precise details are lacking), which is traded as Garra sp. Sunset-Goldscale. The most striking feature is the large, shiny scales on the flanks, which are arranged differently on each individual. Depending on the incidence of light, they shimmer bright blue, red-orange, or golden. The fully grown males (the specimen photographed is approx. 9.5 cm long and the largest animal we have seen so far) have an impressive forehead appendage (scientifically called a proboscis) and snout tubercles. The shape of this proboscis is species-specific. So many new Garra species have been described from India recently that it is not possible to determine the exact species with a reasonable amount of effort, especially since it cannot be ruled out that this is a species that has not yet been scientifically recorded. Our animals most closely resemble the species Garra gotyla, but more detailed, lengthy investigations are necessary to obtain clarity here. In any case, these algae eaters are animals that are not only useful, but also attractive and interesting!

The key aquarium parameters are: clear, low-pollution water, pH and hardness are essentially irrelevant, but the pH value should not fall below 6 on a permanent basis, temperature should be on the low side (20-24°C, possibly 2°C higher for breeding). Very peaceful, sociable (group keeping of 6 or more specimens recommended), plants are not damaged but cleaned. Aufwuchs eaters (algae and microorganisms), therefore do not feed too much nutrient-rich but fiber-rich food. Dry food is accepted without any problems, supplemented with the usual frozen and live food types. Only the males have a proboscis. We are not aware of any breeding reports, but so far all Garra species that have been attempted to breed have proven to be gravel spawners without brood care.

For our customers: the fish have code 416442 (4-6 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Trigonostigma heteromorpha wild

11. December 2025

The harlequin barb, Trigonostigma heteromorpha (formerly Rasbora h.), is one of the most important aquarium fish of all. For this reason, it is traded almost exclusively as a captive-bred species, as the availability of wild-caught fish fluctuates greatly due to seasonal conditions (during the rainy season, the natural habitats are often inaccessible for months).

In the past 25 years or so, we have had fewer than 10 imports of wild-caught Trigonostigma heteromorpha; even this number may be too high, as until 2020 no distinction was made between T. heteromorpha and the very similar T. truncata (see https://www.aquariumglaser.de/en/08-carp-like-fishes-2-barbs-minnows-carps-goldfish-etc/trigonostigma-truncata-2/) from Thailand. We are therefore particularly pleased that we have once again succeeded in importing this species. The fish we are currently offering, which also served as models for the pictures in this post, come from the island of Bintan off the coast of Sumatra, specifically from the area around the city of Tanjung Pinang.

Visually, wild-caught fish hardly differ from captive-bred fish (see https://www.aquariumglaser.de/en/08-carp-like-fishes-2-barbs-minnows-carps-goldfish-etc/trigonostigma-heteromorpha-2/). The latter have been successfully bred since around 1925. It is very unlikely that wild-caught fish have been crossbred into aquarium strains since then. In professional ornamental fish breeding facilities, crossbreeding with other strains is strictly avoided. After all, a professional breeder has to cover the costs every month and, if possible, also make a profit. To do this, the breeding animals must be precisely calculable in terms of spawning date, hatching rate, optimal feed, growth rate, susceptibility to disease, etc. If they are not, professional breeding becomes a gamble that threatens the existence of the breeder. However, since every population of an animal species differs from other populations, even if only minimally, the reluctance of professional breeders (who act this way based on bitter experience) is understandable. Inbreeding, much feared by laymen, has no negative effects on most ornamental fish.

The newly imported wild-caught specimens are something of a holy grail for ambitious aquarists with a thirst for research (but also for professional fish experts), as they enable comparative studies of behavior with conspecifics that have been bred for over 100 years (that’s over 200 generations!). Against the backdrop of the catastrophic global species extinction we are currently experiencing, conservation breeding in aquariums is usually the only option to save endangered small fish species from final extinction. The insights provided by the harlequin barb are invaluable in this regard. Incidentally, the species is currently not considered endangered in the wild.

For our customers: the animals have code 452533 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Corydoras amapaensis

11. December 2025

Finally we were able to import again a small number of the extremely rarely offered long snouted Corydoras amapaensis. The distribution range of this extraordinary species lies in the Oyapock and Amapari river basins in the state of Amapá in Brazil and in French Guiana.

The species is highly variable in respect of coloration. The sexes can be distinguished best by the shape of the spines of the pectoral fins, which are thickened and hairy in males.

For our customers: the fish have code 221754 on our stocklist. Please note that we exclusively supply the wholesale trade.

Text & photos: Frank Schäfer

Barbonymus schwanefeldii

11. December 2025

One of the largest Asian barbs imported for aquarium keeping is Barbonymus schwanefeldii. It used to be known formerly as Barbus. This species, native to Borneo, Malaysia, and Thailand, grows up to 35 cm long. The red coloration of the tail fin is wonderful and is found in this intensity in hardly any other fish. Due to its size, B. schwanefeldii is of course also eaten in its native country and farmed as a food fish. Due to stocking measures for food purposes, it is now considered an invasive species in various parts of the world.

The genus Barbonymus was only established in 1999, with B. schwanefeldii as the genus type. There are nine species in the genus, but only one other species besides B. schwanefeldii is occasionally imported: B. altus. This species is so similar to B. schwanefeldii that there is hardly ever any distinction made between B. schwanefeldii and B. altus in the trade. The only difference between them is their coloration. B. schwanefeldii has clearly visible black stripes on the upper and lower edges of the caudal fin at all ages, which are either completely absent in B. altus or at most only faintly visible. In addition, B. schwanefeldii has a round black spot at the tip of the dorsal fin, which is absent in B. altus. However, specimens are also found in nature that cannot be clearly assigned to one species or the other. There are also bred forms of B. schwanefeldii. One is a yellowish form known as “gold” and the other is an albino form. The latter, however, could also be a bred form of B. altus, as these albinos are occasionally offered as aquarium breeds. Since B. altus appears to remain slightly smaller than B. schwanefeldii, it probably does not need such large aquariums and is correspondingly easier to breed in aquariums.

Both species are also known internationally as “tinfoil barb,” which refers to the strong silver sheen of their scales. B. altus appears slightly more yellowish, which is why it is sometimes sold as “golden tinfoil barb.” In German, both are called “Brassenbarbe” (bream barbel), in reference to the native bream (Abramis brama), a similarly high-backed carp fish. Incidentally, B. schwanefeldii was accidentally named B. schwanenfeldii in its first scientific description. Since there is agreement that this was a mistake – the species was named in 1854 in honor of Mr. H. W. Schwanefeld – the spelling without the “n” should be used.

When it comes to care, you can’t go far wrong with either Barbonymus species. They are large omnivores that also eat tender plants and are happy with any drinking water. The water temperature can be between 22 and 28°C. They are peaceful, sociable animals, but they need space to swim and grow.

Incidentally, in southern Thailand there is a small river near a cave where a holy man once lived. As a result, the river around the cave is also considered sacred, and the fish that live there are not caught or eaten. There, in crystal clear water, you can admire magnificent B. schwanefeldii, which are fed by devout people and swim around near the surface without any fear.

For our customers: we usually do not distinguish between Barbonymus altus and B. schwanefeldii and offer them all as B. schwanefeldii. Depending on their size, they have codes 371401 (3-4 cm) to 371407 (20-25 cm) on our stock list. The yellowish breeding form Gold has code 371502, albinos 371552 (3-5 cm) and 371553 (6-8 cm). In cases where we offer B. altus separately, B. altus measuring 10-12 cm in length have code 371405 on our stock list, and those measuring 5-7 cm have code 371403. Please note that we only supply wholesale customers.

Text: Frank Schäfer, photos: Frank Schäfer, HHach/pixabay, and Erwin Schraml

Petitella bleheri „PLATIN“

11. December 2025

So-called gold tetras are found in many species of characins in South America. Usually, only a few fish in a school are affected by the phenomenon in which guanine, the substance responsible for the shiny silver or gold glitter effect of the fish scales, is secreted at a much higher rate than usual. We explain this in detail here: https://www.aquariumglaser.de/en/fisharchive/hyphessobrycon-saizi-hyphessobrycon-eos-colombian-gold-tetra/) For the reasons described, the golden sheen cannot be fixed in breeding strains. The offspring of all gold tetras look like the regular form.

However, it is precisely in a tetra, in which wild-caught gold tetras are almost never found, that the genetic fixation of the golden sheen has been achieved. Breeders call this attractive silver-shining fish “diamond,” but it is usually referred to as “platinum” in the trade. The precious metal sheen of this rummynose tetra – technically speaking, Petitella bleheri – is due to a random genetic mutation, not parasite infestation. For information on distinguishing between the three rummynose tetras and general care instructions, see https://www.aquariumglaser.de/en/fisharchive/petitella-rummynose-tetras/

For our customers: you can find the animals on our stock list as “Hemigrammus rhodostomus Platinum” with the code numbers 257362 (md) and 257363 (md-lg). Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Ctenopoma kingsleyae

5. December 2025

The tailspot bushfish (Ctenopoma kingsleyae) originates from wooded areas in western Africa. It was one of the first labyrinth fish exported from Africa for aquariums. The first specimens from the lower Niger region arrived in Germany as early as 1912. Strangely enough, this calm, peaceful species was described at the time as very aggressive and incompatible, an observation that was never made again later on. With a maximum length of almost 20 cm (usually 12-15 cm), C. kingsleyae is one of the largest labyrinth fish in Africa.

The tail root spot, which is responsible for the common name, is found in several species. Depending on its mood, it can fade significantly or even appear white – normally it is black. In young fish up to about 5 cm in length, the tail root spot has a golden border. Typical of C. kingsleyae is the large silver spot directly below the eye, which is absent in all other similar species.

In terms of reproductive behavior, Ctenopoma kingsleyae is one of the primitive labyrinth fish. This species does not care for its young. The eggs are drifting on the water surface due to oil deposits and are left to fend for themselves after spawning. The sexes differ only slightly in appearance. Sexually mature C. kingsleyae (from approx. 8 cm total length) have spiny fields behind the eye and on the caudal peduncle, which help the male to wrap himself around the female in a U-shape during mating and turn her onto her back into the spawning position. The spiny field behind the eye is often difficult to see, while the spiny field on the caudal peduncle immediately in front of the caudal root spot appears faintly reddish and therefore often allows gender identification with the naked eye.

Although Ctenopoma kingsleyae may seem unattractive at first glance, these calmly swimming fish with their silvery-white fin edges are a wonderful contrast to colorful tetras, barbs, or cichlids. Very small fish (2-3 cm) and shrimp are regarded as food, but otherwise tank mates, whether animal or plant, are usually completely ignored. The fish are also very peaceful among themselves, regardless of gender.

The chemical composition of the water is irrelevant; any drinking water is suitable for care and breeding. The temperature can range between 20 and 30°C. To stimulate breeding, which is best attempted in winter, a dry period must be simulated. They will eat any standard ornamental fish food of a suitable size, whether dry, frozen, or live. The animals can be particularly pleased by throwing land insects (fat flies, grasshoppers, etc.) onto the water surface. This is the bushfish’s absolute favorite food.

For our customers: depending on their size, the animals have codes 117502 (4-6 cm) to 117504 (9-11 cm) as wild-caught specimens and 117511 (3-4 cm) to 117514 (8-12 cm) as captive-bred specimens. The animals photographed are large captive-bred specimens (117514). Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Nannostomus mortenthaleri

5. December 2025

Nannostomus mortenthaleri from Peru (Rio Nany tributary in the province of Loreto) was the most beautiful new discovery in aquatics in 2000. The close relative of the dwarf pencil, N. marginatus, remains small – approx. 4 cm – and is breathtakingly beautiful in color in the male sex. At least sometimes. Because apart from anatomical details, N. mortenthaleri exhibits behavior that clearly differs from most Nannostomus species. Among conspecifics, N. mortenthaleri forms a distinct hierarchy or pecking order.

Dominant males display an intense red color between the dark longitudinal bands. Lower-ranking males fade and take on the coloration of females. Conversely, dominant females can develop a significant amount of red. N. mortenthaleri‘s behavior is therefore more similar to that of a small Malawi cichlid (Mbuna) than to that of an pencil fish. It is therefore essential to keep this species in a larger group, as otherwise, just like with Mbunas, a tyrant may develop that oppresses all conspecifics so severely that it can even lead to deaths. The gender composition is irrelevant for keeping them in a community aquarium.

In all pencil fish, the shape of the anal fin has proven to be the most reliable sexual characteristic. Unfortunately, the differences are very slight in N. mortenthaleri. The anal fin of adult males is always slightly convex at the front edge, whereas in females it is straight. In addition, females lack the light stripe at the base of the dorsal fin. However, the most reliable way to distinguish between the sexes is by their behavior. We recommend purchasing a group of 10-20 specimens, which should be kept in a larger, heavily structured aquarium (with lots of roots and dense planting). The fish will certainly spawn here (they are open spawners over fine-leaved plants). Although there is hardly any offspring in community tanks, as the adult fish are very cannibalistic, at least you know whether there are really females in the group and can catch them specifically for breeding.

N. mortenthaleri are relatively easy to care for. They adapt well to different water parameters, although soft and slightly acidic water best corresponds to their natural conditions. The water temperature can be between 22 and 28°C. They will eat any standard ornamental fish food of a suitable size. N. mortenthaleri are usually peaceful towards other fish species, but caution should be exercised with closely related Nannostomus species with a similar body shape and coloration.

For our customers: N. mortenthaleri has code 272253 (md) – 272257 (xlg), depending on size. Offspring have code 272259 on our stock list.

Text & photos: Frank Schäfer

Carassius auratus Oranda Panda

5. December 2025

Black and white goldfish are referred to as “magpie-colored” in breeding circles, fish with telescope eyes as “Demekin,” and those with a simple double tail fin as “butterfly tail.” An Oranda, on the other hand, is a goldfish with a hood, in breeding terms. Accordingly, the cute pandas that we were finally able to import again are magpie-colored butterfly tails. But “Oranda Panda” sounds more catchy, don’t you think? There is a difference between the technical language of breeders and the sales designation. In the past, “Oranda Panda” were mainly supplied as Demekins. However, this hardly corresponds to Central European tastes anymore, which is why breeders in Asia now also breed animals with normally developed eyes for this market.

Oranda panda are generally not easy to breed because they are not homozygous. Goldfish have a huge genome, and several alleles are usually responsible for the expression of breed characteristics (veil fins, telescope eyes, hood, etc., but also color). Therefore, there is always a wide range within the same brood of a particular breed. When goldfish that look very uniform are available in stores, this is always due to careful selection and sorting and not to genetic factors. Basically, each animal is individually marked slightly differently, and there are also specimens that have almost no white markings and, conversely, those that have only a few black speckles on a white background.

We only have one regular supplier for these attractive animals, and even he cannot always meet demand. 

For our customers: the animals have codes 817499 (3-4 cm) and 817500 (4-5 cm) on our stock list. Please note that we only supply to wholesalers. Only available in limited quantities.

Text & photos: Frank Schäfer

Channa pyrophthalmus ( = sp. Fire & Ice)

5. December 2025

At the beginning of 2024, this snakehead species, which had long been known in the hobby as Channa sp. Fire & Ice, was scientifically described as Channa pyrophthalmus. So far, it is only known from the extreme southern border area between Burma and Thailand. We are currently able to offer this small and colorful Channa again. In nature, this species only reaches a length of 12-15 cm, but according to Niemeier, aquarium specimens can reach up to 25 cm.

This beautiful species belongs to the close relatives of Channa gachua and, like the latter, is a mouthbrooder. It has also been bred in aquariums. Since the small Channa, which can always be recognized by its characteristic facial markings, is one of the most aggressive members of its genus, it is best kept alone, for which a relatively small aquarium is sufficient. Pairs are only kept together for breeding. This corresponds to their behavior in nature, where the fish also live alone outside of the mating season. If kept in groups, large to very large aquariums with plenty of hiding places for subordinate animals are required.

The best food to give them is insects, e.g., crickets of the appropriate size, which are also readily accepted frozen. However, the fish will accept a wide range of foods: any coarse frozen and live food and, once accustomed, also granules or cichlid sticks; however, they do tend to become overweight, hence the recommendation to feed them insects. The chemical composition of the water is irrelevant for care and breeding; any drinking water is suitable. The temperature requirements are moderate; it is best to keep the species at room temperature (18-22°C) and only increase the temperature by 2-3°C for breeding.

For our customers: the fish have code 409363 on our stock list. Please note that we only supply wholesale.

Literature:

Britz, R., H. H. Tan & L. Rüber (2024): Four new species of Channa from Myanmar (Teleostei, Labyrinthici, Channidae). Raffles Bulletin of Zoology v. 72: 1-25.

Niemeier, D. (2024): Schlangenkopffische. Neustadt am Rübenberge, 552 pp

Text & photos: Frank Schäfer

Apistogramma agassizii PUTUMAYO

5. December 2025

For the first time, we are able to offer a small number of this “new” variant of the well-known Apistogramma agassizii. They were originally by-catches of the magnificent Putumayo variant of A. bitaeniata from Peru (see https://www.aquariumglaser.de/en/fisharchive/apistogramma-bitaeniata-putumayo-4/). We raised a few specimens to see what would become of them, and we can only say: it was worth it!

Just like the aforementioned A. bitaeniata, the Putumayo variant of A. agassizii has a high proportion of yellow in its coloration. There is a broad black band at the base of the dorsal fin. The caudal fin is also edged in jet black. Some (not all!) females of this variant have a double spot on their flanks, as is known from A. gephyra.

In our opinion, the Putumayo variant greatly enriches the known range of A. agassizii; yellow Agassizii have been known for a long time, but it has always been unclear where exactly they come from. Usually, wild-caught A. agassizii from Peru tend to belong to the so-called blue color type, although it should always be noted that there are no “pure-colored” wild-caught populations. See also https://www.aquariumglaser.de/en/25-perchlike-fishes/apistogramma-agassizii-peru-wild-2/

For our customers: the Putumayo variant of A. agassizii has code 614838 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Elassoma gilberti

28. November 2025

This species of pygmy sunfish was only formally described scientifically in 2009. It originates from Florida and Alabama, where it occurs alongside (but not together with) the very similar species E. okefenokee. Like all pygmy sunfish, they are small fish, with males reaching a maximum total length of 3 cm; females remain smaller. The sexes can best be distinguished in adult animals by the edges of their fins. The males have dark gray edges on their dorsal, caudal, and anal fins, which glow a magnificent neon blue when the light comes in the right angle. The females lack this color feature. Elassoma gilberti is capable of changing color very quickly. A male that was just moments ago resplendent in deep velvety black can change to a pale beige color within seconds when disturbed—and the approach of a camera is enough to cause this reaction. It is therefore a rare stroke of luck to capture a dominant black-colored male in a snapshot.

Unfortunately, this gem of a fish is rarely available. In normal dealer tanks, Elassoma gilberti are often very pale in color. This means that there is little difference between them and the well-known Elassoma evergladei (see: https://www.aquariumglaser.de/en/25-perchlike-fishes/elassoma-evergladei-4/). In terms of care requirements—quiet, densely planted aquariums, frozen and live food, room temperature (16-24°C, i.e., no additional heating)—the Elassoma species do not differ. All are continuous spawners during the breeding season. The eggs and, accordingly, the young are tiny, which makes rearing somewhat difficult. Overall, it can be said that the care and breeding of Elassoma correspond to those of the better-known dwarf badids (Dario spp.). The Elassoma gilberti we offer are captive-bred specimens.

For our customers: the fish have code 414732 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Homaloptera ogilviei

28. November 2025

Hillstream loaches belong to the loach family. The most beautiful representatives are found in the genus Homaloptera. Until a few years ago, this genus was very broadly defined; 72 species were described as Homaloptera spp. Today, however, the definition of the genus is much narrower and only six species are assigned to the genus Homaloptera: H. bilineata (Nepal, Burma, Thailand), H. confuzona (Mekong basin), H. ocellata (Java), H. ogilviei (Malaysia, Sumatra, Borneo), H. orthogoniata (Borneo), and H. parclitella (Malaysia, southern Thailand). They all look quite similar. In German, they are sometimes referred to as “Sattelfleckschmerlen” (saddle-spotted loaches), while in English they are called “lizard loaches”.

The English common name is quite apt, as these pretty fish glide over solid surfaces just like lizards, always maintaining contact with the ground. When they are at the frontglass of the aquarium, you can clearly see the two different suction apparatus that these fish have developed: one suction apparatus is located in the “armpits,” i.e., adjacent to the pectoral fins, and the other located in the pelvic area, adjacent to the pelvic fins. The existence of suction apparatus already indicates their habitat: flowing waters with solid ground.

We have been able to import Homaloptera ogilviei from Thailand. This small hillstream loach was first described from Malaysia in 1967 and later also found in Sumatra and Borneo. Its occurrence in Thailand has not been scientifically proven, but was to be expected for zoogeographical reasons. It can be safely assumed that the animals were collected in forest streams in the very south of the country.

With a maximum total length of approx. 5 cm, H. ogilviei are the smallest representatives of the genus known to date in the hobby. Their coloration is very variable, ranging from brown to black tones to brick red. However, the basic pattern is fairly similar in all animals.

These animals are demanding to care for: they require a low-germ environment, and the water must be enriched with humic substances from peat, alder cones, or leaves, otherwise the animals are very susceptible to parasites. In addition, as flowing water dwellers, these fish have a high oxygen requirement. The water should therefore not be too warm; 22–25 °C is ideal. Live food is preferred at first, but later the animals will also accept frozen and dry food. These beautiful fish are very peaceful, but like to impress each other in harmless fights for dominance, which are very interesting to watch. 

For our customers: the fish have code 421612 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Hyphessobrycon flammeus

28. November 2025

One of the first tetras ever imported for aquariums is Hyphessobrycon flammeus. Since its first import in 1924, the species has never disappeared from aquariums, as it is easy to breed and the fish are very productive. Due to its origin (the area around Rio de Janeiro in Brazil) and its pretty red color, the species quickly gained a popular name, namely “Flame Tetra,” especially since the species was still unknown to science at the time of its first import.

Unfortunately, the Flame Tetra is threatened with extinction in the wild, as its natural habitat (coastal forests) is disappearing more and more. There have been no imports for many decades, but by purchasing Flame Tetras, you can actively participate in species conservation, because as long as aquarists demand Flame Tetras, they will continue to be bred and can at least survive in aquariums.

The fish display their optimal coloration in natural conditions: brownish, relatively cool (16-22°C) water colored by humic substances. However, the fact that this species has existed for 100 years without any “blood renewal” in the hobby clearly shows that the Flame Tetra is an adaptable animal that can thrive under a wide variety of conditions. Any commercially available ornamental fish food of a suitable size is accepted. An important note: Hyphessobrycon flammeus kept individually or in pairs can become very aggressive towards tank mates, so please keep at least 10 specimens together, regardless of gender. Males differ from females in that they have a stronger black border on their anal fin and black ventral fin tips.

For our customers: depending on their size, the animals have codes 260300 to 269304 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Protopterus annectens Nigeria

28. November 2025

There are four species of lungfish in Africa, some of which are difficult to distinguish from one another. The situation in Congo is particularly confusing (see https://www.aquariumglaser.de/en/29-lungfishes/lungfishes-from-the-congo/). Only the species Protopterus dolloi is always easy to recognize due to its elongated body shape. The surest way to distinguish between the three species Protopterus aethiopicus, P. annectens, and P. amphibius is by the base of the dorsal fin. In P. amphibius, this begins just behind the pectoral fins, in P. annectens approximately halfway between the pectoral and pelvic fins (slightly closer to the pectoral fins), and in P. aethiopicus behind the midpoint between the pectoral and pelvic fins. Coloring characteristics are largely useless, as there is a very strong individual color variation. It is said that P. amphibius (this species only occurs in southeastern Africa and is therefore hardly ever exported, as there are no regular ornamental fish exports from the area where P. amphibius occurs) retains its external gills the longest, but P. annectens and P. aethiopicus also often do so for a very long time (see below). 

In any case, Protopterus annectens (West African lungfish) from Nigeria is most commonly found in the trade, even if this “frequency” is very relative. After all, the fish reach lengths of around one meter and are very incompatible with each other. For this reason, only a few specimens are imported each year.

We usually import these animals with a length of 15-25 cm. This means that the largest of them are just reaching sexual maturity. The species P. annectens is the only species of African lungfish in which scientific studies on externally recognizable sexual differences have been carried out on wild specimens to date. According to these studies, the males have longer and broader heads. Despite their lung respiration, P. annectens retain their external gills for many years, which are typical of all lungfish species as larvae, making them resemble newt larvae. Each West African lungfish has a unique body pattern. Within the same import and from the same catch area, there are leopard-like spotted and almost monochromatic animals. This has no significance in terms of gender or origin. 

Surprisingly, these large animals prefer to eat relatively small types of food. Although small fish are always at risk in their presence, worm food or granules are clearly preferred; in addition, the animals accept many types of frozen food, insects, etc. They find their food mainly through their sense of smell. Injuries often occur among them during feeding, as the greedy fish snap blindly around them. Fortunately, injuries heal well and the regenerative capacity of these primitive fish is legendary. 

Observing these animals (which are normally quite sluggish) is very interesting. They move their thread-like fins as if they were arms and legs. When aggressive, the attacker opens its mouth wide and stretches its “arms” upward. There is still much to learn about the behavior of these animals. The genus Protopterus has existed for about 400 million years, and the age of the modern species now in existence is estimated at about 26-42 million years (depending on the author, these figures vary considerably).

The males of P. annectens grow larger than the females. The species practices brood care in the male sex. During the dry season, the fish burrow into the ground and survive the drying up of their habitat in a cocoon; in this “dry sleep,” during which their metabolism is greatly reduced, lungfish can survive for several months, allegedly even years. Spawning occurs when the rainy season begins and the water rises again. Spawning takes place in a chamber in the ground, which is connected to the open water by a tunnel system. 

For our customers: depending on their size, the animals have codes 167602 (12-15 cm) to 167607 (60 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Petitella – Rummynose Tetras

25. November 2025

The rummynose tetras are a beautiful eye-catcher for any aquarium with peaceful fish. A shoal of these animals, and there should always be 15 – 20 specimens if possible, delights every observer because these animals really do swim permanently in a shoal; the vast majority of so-called shoal fish among aquarium fish do not do this. They tend to swim around the aquarium in scattered pools and only swim close together when danger threatens. Rummynose tetras are not difficult to care for and so they swim in many aquaria. Only the correct naming of the species is not easy. We know of three species that have been confused again and again. They used to be divided into two genera (Hemigrammus and Petitella), but nowadays all three are classified as Petitella: P. rhodostoma (formerly: Hemigrammus rhodostomus), P. bleheri (formerly: Hemigrammus b.) and Petitella georgiae.

 

These three species have been and are so often confused that you can get really confused. In fact, it’s relatively simple: the fish on the market are almost always Petitella bleheri, but they are almost always referred to as Petitella georgiae. Basically, it doesn’t matter which of the three species you buy, as they don’t differ in their requirements. Nevertheless, we will list the differences here for those who want to know exactly.

E. Ahl described a rummynose tetra as Hemigrammus rhodostomus a long time ago, in 1924. It was found near Belem in Brazil. And so, namely as Hemigrammus rhodostomus, every rummynose tetra in the aquarium hobby was subsequently named. It was certainly noticed that the fish looked slightly different depending on where they were found, but this was thought to be an intraspecific variation.

In 1964, the tetra specialist J. Gery and H. Boutiere described a species very similar to the already known rummynose tetra as Petitella georgiae. The differences in the coloration of the two species are insignificant, the reason for the species separation was due to differences in the dentition. This new species originates mainly from the upper reaches of the Amazon in Peru. It was not particularly widespread in the hobby because it is somewhat less colorful than the rummynose tetra, which was already known.

However, the most beautiful rummynose tetras came and still come from the Rio Negro. They have a magnificent red head coloration that extends far beyond the gill covers. Coveted fish need their own trade name and so the new name Petitella georgiae was used for this tetra without checking the accuracy of this undertaking.

In 1986, J. Gery together with V. Mahnert described this reddest of all rummynose tetras as a new species, Hemigrammus bleheri, and the chaos was perfect because each of the three species had already been illustrated in the literature under an incorrect name.

P. bleheri can always be easily recognized by the fact that, unlike the other two species, it does not have a black longitudinal band on the caudal peduncle, but only a pale grey line. Petitella georgiae and P. rhodostoma have a distinct, clearly visible dark longitudinal band and can hardly be distinguished visually. In acclimatized animals it is best to look at the end of the caudal peduncle. Petitella has only one spot at the top in front of the caudal fin, P. rhodostoma has a spot at the top and bottom.

We mostly import P. bleheri from Brazil, but for reasons of our in-house merchandise management analysis it sails under the name “Petitella georgiae”, but from time to time we also have wild-caught “real” P. georgiae from Peru in stock. P. rhodostoma is hardly ever sold under its real name. The pictures we show here are of so-called by-catches, which we sorted out from imports of other fish species. P. bleheri is not only offered as a wild catch, but also as offspring. There are also cultivated forms of P. bleheri: Gold, albino and platinum forms show the large scale on which this species is bred.

In terms of care, it can be said that the adaptability to different water conditions is so good that it can be said that rummynose tetras of all kinds can be kept well for years in any tap water suitable for drinking. Their coloration is optimal in water to which humic substances have been added. Soft and acidic water is required for breeding. The sexes differ in shape (females are larger and rounder in the belly area) and the males have small hooks on the anal fin with which they get entangled in the net. The water temperature should be between 24 and 28°C, a little higher for breeding, sometimes a little lower won’t do any harm either. They will eat any common ornamental fish food of a suitable size, plants remain undisturbed. Petitella are very peaceful towards all fish species.

For our customers: unfortunately, for accounting reasons, it is very difficult to change the names in our stock list. For this reason, P. bleheri cultivated forms (Gold 257301-257303, Albino 257352 and Platinum 257362-257363) and captive-bred specimens (code 257201-257205) can be found under Hemigrammus rhodostomus, wild-caught P. bleheri from the Rio Negro under Petitella georgiae (code 278001-278005) and the “real” P. georgiae from the upper Amazon (Peru) under P. georgiae/real wild PERU (code 278014). Please note that we only supply the wholesale trade.

Text & photos. Frank Schäfer

Maylandia sp. „Daktari“

21. November 2025

The colorful rock cichlids (Mbuna) of Lake Malawi are mainly kept for their bright colors, but they actually have more to offer in terms of behavior than just looking good. Maylandia sp. Daktari—a species not yet scientifically described—occurs only in a relatively small area in four populations; two of these populations are indistinguishable in appearance. In the population from Undu and Hai Reef in Tanzania, the dominant males are bright yellow, while in the Chiwindi and Liutche populations in Mozambique, the dominant males have a blue tinge over their backs. Almost all specimens available in the trade are offspring of the yellow morph.

By Mbuna standards, this species is considered peaceful and is also one of the smallest Mbunas, growing to only about 10 cm in length. However, males can be very aggressive towards each other. It is usually recommended to keep one male with several females per aquarium. However, there are now also many aquarists who successfully keep several males and several females. Non-dominant males take on the coloration of females and are then safe from persecution by the alpha male; the “real” females are relieved of the constant pursuit of the alpha male, as he puts just as much energy into courting the “false” females. Overall, this creates a relatively low-stress community.

Maylandia sp. Daktari (this species is also referred to in the literature under the synonyms Metriaclima sp. Daktari and Pseudotropheus sp. Daktari) lives in the transition zone between rock and sand. At the foot of a rock, a territorial, dominant male (called an alpha male) digs a tunnel that serves as a spawning ground. M. sp. Daktari is actually a planktivorous fish that picks small food organisms (plankton) from the open water column. Only the territorial male switches to an aufwuchs-eating lifestyle. Since this is a very nutrient-poor food source, a territorial male defends his territory very aggressively against unwanted competitors. It is assumed that alpha males cannot afford to leave their spawning territory to search for food, as the sparse aufwuchs growth would be eaten by other fish during this time.

Like all Mbuna, Maylandia sp. “Daktari” is an agamous mouthbrooder in the female sex, i.e., the two sexes do not form a bond beyond spawning, and the female is solely responsible for incubating the eggs in her mouth cavity.

For our customers: the animals have code 568263 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Synodontis flavitaeniatus

21. November 2025

This attractive squeaker catfish originates from the lower Congo (for example in the Pool Malebo area, formerly known as Stanley Pool). With a final size of around 20 cm, it is one of the medium-sized species of the genus. In the past, this catfish was considered to be as sensational as the zebra catfish (L46, Hypancistrus zebra) was a few decades later. In Aquarium Atlas, Volume 1, we read: “One of the most beautiful squeaker catfish, but very rare and expensive. Only about a dozen animals are caught each year.” Well, that is a nostalgic look back at the past; basically, Synodontis flavitaeniatus is by no means a common fish, but that is usually due to low demand rather than anything else. At present, however, this catfish is indeed becoming a rarity, as importing fish from the Congo is becoming increasingly complicated and breeding such catfish on a commercial basis is hardly worthwhile. This requires a consistently high demand as a basic prerequisite.

We haven’t had any S. flavitaeniatus in our facility for several years now. What is striking about this species is, on the one hand, the teeth, which already begin on the outside of the upper lip, and, on the other hand, the striped pattern. The former indicates that S. flavitaeniatus feeds in nature on animals that sit in depressions and which the catfish can pick out with its special teeth. The latter can be explained when you see this Synodontis sitting in relatively finely branched roots, which it prefers to all other hiding places. This is because it then visually disappears into nothingness. The reddish-yellow-brown striping that is so conspicuous in swimming animals is perfect camouflage in this environment!

S. flavitaeniatus can be kept in aquariums for decades without much effort. Like most squeaker catfish, they form a hierarchy among themselves. This regularly results in skin abrasions, but these heal easily and without complications. The animals are relatively peaceful towards fish of other species. Any tank mates should not be too delicate, but S. flavitaeniatus are a wonderful addition to a West African aquarium with medium-sized tetras, barbs, and cichlids. These crepuscular fish need daytime hiding places, but after a certain acclimatization period, they are also very active during the day, especially at feeding times. The chemical composition of the water is irrelevant; any drinking water is suitable for their care. The water temperature can range from 22-28°C. They will eat any standard ornamental fish food of a suitable size.

For our customers: depending on their size, the animals have codes 179500 (3-4 cm) to 179504 (10-12 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Baryancistrus xanthellus L18

21. November 2025

The fishing season for the beautiful Golden Nugget catfish of the genus Baryancistrus lasts from around the end of May to the end of September. Due to the varying sizes of the spots on their bodies and the varying widths of the fin edges on their dorsal and caudal fins, as well as the varying intensity of the yellow coloration of the spots, several L numbers have been assigned to these animals for aquarium purposes: L18, L81, L85, and L177. In addition, there are other local variants, which are given a letter in addition to the L number, such as L81b (https://www.aquariumglaser.de/en/10-catfishes/10b-catfishes-suckermouths-plecos-and-l-numbers/a_new_golden_nugget_en/),  L81c (https://www.aquariumglaser.de/en/10-catfishes/baryancistrus-xanthellus-l81c-sao-felix-2/) or L81n (https://www.aquariumglaser.de/en/10-catfishes/10b-catfishes-suckermouths-plecos-and-l-numbers/baryancistrus_sp_l81n_en/). From a scientific point of view, however, they all belong to a single species, namely Baryancistrus xanthellus, which is widespread in the Rio Xingu and its tributaries in Brazil. All differences can only be seen in young animals (up to approx. 15 cm in length). When adult (from approx. 20 cm), they all look the same (at least as far as we know); the maximum length given in scientific literature is 30 cm (total length, i.e. including the tail fin). The spots are then very small and the yellow fin edges have almost disappeared. For adult animals, see https://www.aquariumglaser.de/en/10-catfishes/10b-catfishes-suckermouths-plecos-and-l-numbers/baryancistrus_xanthellus_l18_adult_en/.

The classic among the Golden Nuggets is still L18. Unlike other armored catfish from the Rio Xingu, this species is not directly threatened by the construction of the Belo Monte dam, as they are inhabitants of calmly flowing water. These biotopes will continue to exist despite the dam. From an aquaristic point of view, all Baryancistrus are a challenge for experts, as they need vast amounts of food, high water temperatures (28-32°C), large aquariums, and optimal water care in order to grow into large, breedable specimens. B. xanthellus are generally peaceful towards each other and towards fish of other species; as long as they have their striking juvenile coloration, they are even quite sociable and like to stay in groups with their own kind. Later, they become more and more solitary.

For our customers: L18 have – depending on size – code 26480-L 018-0 (3-4 cm) to 26480-L 018-8 (25-30 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Hyphessobrycon negodagua

21. November 2025

At present the small tetras of South America experience a new boom. Numerous species have been and are being described scientifically. Thus also the ornamental fish collectors leave their beaten tracks and look for these animals, particularly since initially peppered prices are paid for the novelties. Naturally, such a thing only works for a short time, then offspring of the particularly attractive species come onto the market, the less attractive ones disappear again and wild catches only come to us once in a blue moon as rarities for a few specialists. 

One of these new species is Hyphessobrycon negodagua, which was scientifically described in 2001. Its area of origin is in the northeast of Brazil, in the state of Bahia. There, this tetra with a maximum length of 3 – 3.5 cm inhabits the Rio Pratinah, a tributary of the Rio Santo Antonio, which in turn drains into the Rio Paraguaçú, which is one of the important coastal rivers of Brazil without connection to other river systems. H. negodagua differs from almost all other Hyphessobrycon species by the absence of the typical tetra adipose fin in most specimens, the unique coloration of the males in courtship display also makes them distinctive. Freshly imported and not yet acclimated animals are silvery, but acclimated males show already after a few days their fiery courtship dances, during which they turn black, which contrasts very effectively with the white fin seams. The fluttering courtship swim of this pretty species prompted Hans-Georg Evers to call it the “Butterfly Dwarf Tetra”.

The care of the animals is simple and corresponds to that of other small tetras. Incidentally, the species name “negodagua” refers to a mythical man-like monster (Nego d’agua) that lurks at the bottom of rivers and attacks inattentive fishermen at night. Why scientists associated the small, peaceful tetra with this monster, they do not reveal….

For our customers: the animals have code 261232 on our stock list. Please note that we only supply wholesale. 

Text & photos: Frank Schäfer

Betta simplex

14. November 2025

This small (5-6 cm) mouthbrooding species from Thailand is a very nice addition to the assortment of wild collected Betta we occasionally have in stock. Betta simplex is a close relative to the species Betta picta from Java, Betta falx from Sumatra, and Betta taeniata from Borneo. All the mentioned species share obviously the same ancestor. 

The males have a broad green to blue (reddish in B. falx) seam in the anal and the caudal fin, which is almost lacking in females.

Our B. simplex are young adults and particulary nice at that age. In contrast to many other mouthbrooding Betta species, B. simplex is not adopted to soft, acidic water, for the natural habitat (near the town of Krabi in the south of Thailand) is characterised by lime stone hills. Like in most species of mouthbrooding Betta the males are compartively peaceful against each other and one can keep usually several males together in the same tank without any problems. However, the aquarium should be well furnished and contain well growing plants.

For our customers: the fish have code 387752 on our stocklist. Please note that we exclusively supply the wholesale trade.

Text & photos: Frank Schäfer

Fundulus julisia

14. November 2025

The global loss of biodiversity, i.e., species diversity, is terrible. People who are particularly interested in nature, and this includes aquarists in particular, feel the extinction of species almost as physical pain. Small fish species are among the few organisms that are very well suited for conservation breeding over a very long period of time and many generations. This is a proven fact, and several fish species that have become extinct in the wild continue to live in aquariums. This means that future generations of humans may be able to reverse the mistakes made by our generation and return species that were once extinct from the aquarium back to a renaturalized habitat.

Unfortunately, species that are critically endangered are usually not very attractive at first glance. This is a shame, because the best life insurance for an animal species is still the highest possible demand in the trade. Then many breeders are interested in satisfying this demand and conservation breeding is on a firm footing – even if not necessarily for idealistic reasons. 

Fundulus julisia is an example of a highly endangered species that is only cared for and bred by a very small number of specialists. Due to large-scale changes to the environment in its original habitat in the US state of Tennessee caused by water engineering and agriculture, this once widespread species has been pushed back to the headwaters of a few small streams. There, during the spawning season, the magnificently colorful males are very easy prey for fish-eating birds (e.g., herons). In addition, invasive gambusia fish deliberately released into the wild prey on the young of Fundulus. The survival of Fundulus julisia in the wild is therefore like dancing on a razor’s edge: something can go wrong at any time. 

For several years now, we have been offering F. julisia from German hobby breeders. These animals are kept by the breeders in natural conditions in the open air. In the fall, when the fish go into hibernation, we receive the surplus offspring. Unfortunately, the animals then only show a hint of their true colors. This stands in the way of widespread marketing. Only connoisseurs and experts know what a treasure they are getting when they give Fundulus julisia a habitat (and a chance to survive) in an aquarium.

Here are the care details in bullet points: Water: not too soft and slightly alkaline; tap water is usually very suitable. Temperature: varies depending on the season. Hibernation at 10-15°C under short-day conditions (less than 10 hours of light per day) is necessary, otherwise the animals will not be in the mood to mate the following spring. The rest of the year 18-26°C. Food: all common dry, frozen, and live foods are readily accepted. Social behavior: peaceful fish that likes to swim in groups with conspecifics. Sexual differences: males are more colorful, with a much larger anal fin and a light band at the edge of the dorsal and caudal fins (difficult to see outside the breeding season). Size: 6-8 cm.

For our customers: the animals have codes 326602 (sm) and 326603 (lg) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Mastacembelus unicolor

14. November 2025

The large (around 60 cm) spiny eel Mastacembelus unicolor was scientifically recorded early on. The two researchers Kuhl and van Hasselt discovered it in the western part of Java during their stay there from 1820 to 1823 and also made a drawing of the animal. The two paid for their thirst for knowledge with their lives, dying of tropical diseases in 1821 (Kuhl) at the age of 24 and in 1823 (van Hasselt) at the age of 26. Their records and collected specimens were later used by other scientists as the basis for species descriptions. Cuvier described Mastacembelus unicolor on this basis in 1832.

M. unicolor remained completely unknown in aquariums for a long time, although the species is widespread in Indonesia but apparently not common anywhere. We first received two adult specimens of the species by chance in 2018 (see https://www.aquariumglaser.de/en/22-spiny-eels/mastacembelus-unicolor-2/) and in 2024 in a younger specimen measuring 20-25 cm in length (https://www.aquariumglaser.de/en/fisharchive/mastacembelus-unicolor-4/). Now, for the first time, we have managed to import a slightly larger number of juvenile animals (10-20 cm in length). The conclusion from this is that juveniles differ greatly in color from sexually mature specimens. The species-typical snow-white stripe at the edge of the dorsal, caudal, and anal fins only develops from a length of about 20 cm; fortunately, this color change can be observed in all transitions in our current import. And we learn something else from this import: there are two color phases in young M. unicolor, one more reddish and one blackish-brown. 

Once again, this shows how valuable wild-caught imports are for gaining knowledge, especially of fish species that, due to their characteristics (in this case, their achievable final size), are only of interest to a few specialists as aquarium fish.

For our customers: the animals have code 426722 on our stock list. Please note that we only supply wholesalers.

Text & photos: Frank Schäfer

Synodontis angelicus

14. November 2025

With 133 species, the squeaker catfish (Synodontis) inhabit practically the entire African continent. The smallest species grow to 6-7 cm in length, the largest to 60-70 cm. They play a very minor role in aquariums. Only the Upside-Down catfish (Synodontis nigriventris) and a few species from Lake Tanganyika are true aquarium fish with a larger following. Of the large number of other species, only S. eupterus is frequently found in the trade because it is relatively easy and productive to breed; the rest are considered to be a case for catfish specialists.

Synodontis angelicus comes from the Congo, a medium-sized species usually 15-25 cm long, but the largest specimen ever measured is said to have been an impressive 55 cm! Before the large number of black plecos with white spots from South America became known, S. angelicus (the species name translates as “angel-like”) was considered the most beautiful catfish species and was even given the German common name “Perlhuhnwels” (guinea fowl catfish). The common English name is „Angel squeaker“. This honor has hardly been bestowed on any other Synodontis species. 

Even today, S. angelicus is still a beautiful fish, but its dark side is also well known. It can be very quarrelsome, especially when only one or a few specimens are kept together, and will chase all the other fish. There are significant individual differences, but it is important to be aware of this, because where can you put the fish if it turns out to be a tyrant? Similar to cichlids, the best way to counteract this unpleasant trait is to keep several (10+) specimens in aquariums that are as large as possible with plenty of hiding places.

S. angelicus is undemanding in terms of food and water chemistry and can be classified as easy to care for. The water temperature should be between 24-28°C.

For our customers: depending on their size, the animals have codes 172000 (3-4 cm) to 172006 (12-15 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Curimata vittata

14. November 2025

The genus Curimata currently comprises 13 species; only one of these occasionally finds its way into our aquariums, namely Curimata vittata. The other species simply offer no incentive to keep them. They are shiny silver-colored animals that can reach a length of 15-20 cm and feed mainly on plant material.

Curimata vittata also reaches this length, but unlike its genus counterparts, it is quite attractively colored. An irregular tiger pattern runs across its back, its generally silver-colored flanks shine greenish or golden depending on the incidence of light, and a golden-yellow band runs along the middle of its body.

The strange mouth structure shows that they are Aufwuchs feeders. From our hobby, we are familiar with kissing gouramis (Helostoma) and flagtail tetras (Semaprochilodus), which also feed in this way. Only fine particles should be fed to these fish, as they have a narrow throat. Suitable foods include plant-based flake food finely rubbed between the fingers, frozen cyclops, Artemia nauplii, or finely ground oatmeal (caution: this pollutes the water heavily). C. vittata is widespread in the Amazon, upper Orinoco, and Essequibo River; our specimens come from Colombia. They are peaceful, somewhat shy fish that should definitely be kept in groups. Single fish are extremely shy.

For our customers: the animals have code 251203 on our stock list. Please note that we only supply wholesale customers.

Text & Photos: Frank Schäfer

Fluviphylax rubens

7. November 2025

The miniature lampeyes of the genus Fluviphylax are the smallest relatives of killifish. When fully grown, their body length is less than 2 cm standard length (i.e., without the tail fin), usually around 1.5 cm. Until recently, these dwarfs were only known from Brazil, from where we were occasionally able to import them, but that was quite some time ago; we also once received animals from Venezuela that are very similar to F. rubens (see https://www.aquariumglaser.de/en/18-toothcarps-killis-and-livebearers/dwarf_lampeyes_fluviphylax_from_venezuela_en/). The eight scientifically described species of Fluviphylax are currently placed in their own family, the Fluviphylacidae.

It was not until October 2024 that the first species from Colombia was described, namely Fluviphylax rubens. We are very pleased to be able to offer this biological peculiarity for the first time (recognized).

The differences between Fluviphylax species are subtle, which is hardly surprising given how delicate these creatures are. The decisive criterion for us in classifying our Colombian import as F. rubens is primarily the males’ anal fin, which is enormously elongated in comparison to their body height. The strong red coloration that the type specimens in the field exhibited, and which led to the species name “rubens” ( = the reddish one), is only faintly visible in our males. However, this is a phenomenon that many red-colored fish exhibit in the early stages after importation and, in our opinion, is not particularly significant.

However, we were quite surprised to find that, upon reviewing the photos of our new arrivals, a second species could clearly be identified. We have not yet determined the species of these fish; in any case, it is not possible for us to sort our imported animals. This would cause too much stress for these miniature fish, which we want to spare them at all costs. The most striking difference between the species is easiest to see in reflected light photos. This makes the luminous marks along the edge of the belly particularly prominent. While Fluviphylax rubens has a row of luminous marks along the edge of its belly, the unidentified species has a continuous band. The unidentified species also has different body proportions (slightly more elongated) and a differently shaped anal fin. It is also known from Brazil that several Fluviphylax species occur in close proximity to each other at some sites (in this case F. obscurus, F. simplex, and F. zonatus, all from the Manaus area).

To our knowledge, successful breeding of Fluviphylax has only been reported once, namely by Bork and Mayland in 1994; Those with a special interest are referred to this article. There is not much to say about care at this point; such fish naturally belong in the hands of specialists who know what they are doing and are familiar with the available literature on these animals.

For our customers: these creatures have code 325691 on our stock list. Please note that we only supply wholesale customers.

Literature:

Bork, D.& H. J. Mayland (1994): Fluviphylax pygmaeus. Ein (beinahe) unbekannter Poeciliidae, der erstaunlich große Eier legt. Das Aquarium, Heft 298 (4/1994):14-15

Huber, J.H. (2024): Short description of Fluviphylax rubens n. sp., a new so-called lampeye Cyprinodontiformes from Colombia with exceptionally few dorsal-fin rays. Cybium, 48 (4): 327-331

Text & photos: Frank Schäfer

 

Apistogramma flabellicauda

7. November 2025

There are three species of Apistogramma that even a very experienced Apistogramma enthusiast cannot reliably distinguish from one another: A. uaupesi (scientifically described in 1980 from the Rio Uaupes in Brazil, previously given the common name “segelflossen ( = sailfin) apistogramma” by Schmettkamp, later referred to by various authors as “red-wedge ( = rotkeil)” or “blood-throated ( = blutkehl) apistogramma”), A. flabellicauda and A. lineata; the latter two were described in 2011 from the upper Orinoco basin in Colombia. It has been known for decades that A. uaupesi is extremely polychromatic, i.e., at least the males can look very different. Aquarists repeatedly report that different color forms always occur within the same brood. This corresponds to the situation in nature, where males with different colors and markings are found at the same location. Since A. flabellicauda and A. lineata have been described solely on the basis of color characteristics, which have not proven to be consistent in breeding stock, the validity of these two species is repeatedly questioned.

There is no “final” decision on this issue, nor is one to be expected. Basically, it doesn’t matter whether an Apistogramma is referred to as A. flabellicauda or A. uaupesi “upper Orinoco.” On the other hand, there is always the risk that the important location data will be lost when specimens are passed on to other enthusiasts. In such cases, it therefore makes sense to use a different scientific name, if one is available, regardless of whether it is considered valid or a synonym. Even if A. uaupesi, A. flabellicauda, and A. lineata are most likely synonyms according to the majority of existing species concepts, this is irrelevant for breeding practice. In breeding, it is important to preserve the genetic identity of populations, i.e., members of the same species that have no contact with each other under natural conditions. Only such animals are worth preserving from the point of view of species conservation and systematics, while crossbreeding of different local forms leads to a domesticated animal. Domesticated animals are certainly suitable for community aquariums, but have no value beyond that. 

Apistogramma flabellicauda, like the other two “species,” are adapted to fairly specific biotopes. It is widely reported that the substrate in their natural habitat consists of fine white sand. Within the biotope, it is primarily dead wood and dead leaf accumulations that structure the underwater landscape. The water is clear and clean, with a very low pH of around 4.5 and hardly any detectable hardness. These factors are important for care insofar as their effects on the fish must be imitated. Fine sand is needed for chewing, otherwise there is a risk of disease in the mouth and throat. Low pH and hardly any hardness ensure low germ pressure in the water. If this can be guaranteed in another way, both values can be neglected. Only for breeding is it necessary to ensure near-natural water values, otherwise the spawn will not develop. The water temperature should be in the range of 24-28°C, at the upper end for breeding and at the lower end for normal care. They will eat pretty much any standard ornamental fish food of a suitable size, but Tubifex and red mosquito larvae (bloodworm) should be avoided if they come from waters with high levels of organic pollution. However, well-rinsed and clean Tubifex and red mosquito larvae, which are low in bacteria, are considered safe, at least in our wholesale business.

For our customers: the animals have code 619152 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Bunocephalus aleuropsis and B. colombianus

7. November 2025

We received four larger (10-15 cm) banjo catfish from Colombia, which turned out to be four different species. The two Xyliphius specimens were identified relatively quickly; one is a specimen of X. lepturus and the other is an almost entirely black specimen of X. melanurus (see https://www.aquariumglaser.de/fischarchiv/xyliphius-cf-lepturus-und-x-cf-melanurus/). The two “real” Bunocephalus were more difficult to identify. One animal looks very similar to a “normal” B. coracoideus, but has significantly shorter coracoid processes (see https://www.aquariumglaser.de/en/fisharchive/bunocephalus-coracoideus-4/ for what these are). This is probably B. aleuropsis, a species described from Peru as early as 1870, which is widespread in the Amazon region and apparently also in the Orinoco.

The second species has still not been identified with certainty; all characteristics strongly suggest B. colombianus, but our specimen has no recognizable coracoid processes, whereas the specimen on which the first description was based, the holotype, has very clearly pronounced processes. However, since our specimen has a very high back and is well-fed, it may also be that the coracoid processes are simply too far inside the body to be visible. However, a comparison of this animal with previous imports of B. colombianus (of which we unfortunately have no photographs of the abdomen) shows a great deal of similarity in appearance.

What is particularly striking about these two fish is how differently shaped their mouths are. While B. aleuropsis has a comparatively narrow mouth opening, that of B. colombianus is strikingly wide.

For our customers: B. aleuropsis has code 212863 and B. colombianus has code 212913 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Bunocephalus coracoideus

7. November 2025

Banjo catfish (Bunocephalus) are extremely common in nature. That’s why we always have them in stock. We usually refer to these animals as Bunocephalus coracoideus, which may be correct in many cases. But when you look at such a swarm of banjo catfish, you notice that there are always other species mixed in. As a rule, it is not possible to identify them with reasonable effort, let alone sort them, but it is extremely exciting to raise and observe a group of perhaps 20 of these animals in an aquarium. Then you notice how variable these animals are in coloration, that there are clear differences in anatomy (especially the bone ridges along the middle of the back in front of the dorsal fin), and also that there are species that prefer to burrow more than others.

As mentioned, Bunocephalus are usually not identified in more detail in the trade and are marketed under the name B. coracoideus. It gets tricky when Bunocephalus that are visually distinguishable from the “mainstream” are imported; we try to identify these as accurately as possible, of course. That is why we will briefly describe here what we currently understand to be the “real” B. coracoideus.

The species name “coracoideus” refers to a very characteristic feature of this species, the coracoid bones. These are bony processes that, in this case, support the pectoral fins. Since these bony processes lie directly under the skin, they are also clearly visible in living animals. According to current knowledge, B. coracoideus has the most pronounced coracoid bones in the genus Bunocephalus, which currently comprises 14 species. The ventral parts of the processes extend almost to the base of the ventral fins. A second feature that characterizes the species B. coracoideus very well are the bony protuberances along the middle of the head. Three distinct larger elevations can be seen here, and a small one immediately in front of the dorsal fin. This combination of features allows for a fairly reliable identification in most cases. Colouring is not such a good characteristic, as it is very variable. However, it almost always consists of a front part covering the head that differs from the colouring of the tail. A well-known synonym for B. coracoideus is B. bicolor; “bicolor” means “two-colored”.

B. coracoideus is widespread throughout the Amazon region and can therefore come to us from practically all ornamental fish exporting countries that have access to the Amazon. Currently, for example, we have some very beautiful specimens from Colombia in stock. However, genetic studies have shown that different populations of B. coracoideus, which are visually indistinguishable from one another, differ so significantly in terms of their genetic makeup that they should actually be considered different species. This is important to know in practice, especially when attempting to breed them. If you want to breed Bunocephalus, which is entirely possible, although not commonly practiced, you should always assemble your breeding stock from animals from the same import to avoid producing unwanted hybrids.

For our customers: B. coracoideus has code 212901 (2-3 cm) to 212907 (10-12 cm) on our stock list, depending on size. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Silver Molly Orange Spots

7. November 2025

Whenever one of our suppliers offers a “new variety,” we order a box to see what it is. However, we know from experience that the term “new variety” is often used very flexibly. The spectrum ranges from “old news, but new to our list” to “wow, we’ve never seen anything like this before.” 

This time it was a molly that was delivered to us as a “new variety” under the variety name “Spring.” Why does an orange-spotted silver molly remind you of spring? We don’t know. However, these animals from the group technically classified as Poecilia latipinna are not entirely uninteresting. The alpha male, i.e., the highest-ranking animal, is almost entirely orange in color. Many females and lower-ranking males, on the other hand, only have orange stripes. In between, there are all conceivable transitions. This results in a very colorful picture and corresponds quite well to the conditions in wild mollies, where only the alpha fish is colorful. A group of these mollies is therefore certainly an enrichment of the assortment, but individual fish are less so.

For our customers: the animals have code 432327 on our stock list. Please note that we only supply wholesale.

Text & photos: Frank Schäfer

Hoplisoma colossus ( = CW45, Corydoras sp. „Lessex“)

31. October 2025

In 2009, we successfully imported a large, beautiful armored catfish from the Rio Jutai in Brazil for the first time. At the time, we referred to the animals as Corydoras sp. aff. armatus because their particularly high dorsal fin and general body shape were very reminiscent of C. armatus. However, C. armatus (current name: Hoplisoma armatus) never has a bright orange-yellow neck spot or orange-yellow gill covers like the new import. The exporters named the fish “Lessex”; later, Ian Fuller gave it the code number CW45. In 2023, the scientific description of the species was published as Corydoras colossus. Currently, C. colossus is classified in the genus Hoplisoma, so its correct name is Hoplisoma colossus.

So far, this species has only been found in the Rio Jutai. This river has dark water with a pH value of around 6 and very low hardness. The bottom usually consists of fine, white sand with larger deposits of dead leaves from land plants. The striking orange-yellow shiny areas are interpreted as a warning to potential predators, as both the dorsal fin and the pectoral fins are connected to poison-producing glands. Anyone who has ever been stung by a armored catfish knows that this can be very painful. Since the production of the poison is energy-intensive, it has proven advantageous in the course of evolution to warn potential predators first. If the predator (usually a bird) still tries to eat the fish, it experiences a painful surprise and avoids any prey with such conspicuous coloring in the future.

In the aquarium, Hoplisoma colossus are magnificent and undemanding armored catfish that adapt well to different water conditions. However, they develop their most beautiful coloration under nature-like conditions. The animals are easy-going omnivores that are very peaceful among themselves and towards other fish species. Like almost all armored catfish, H. colossus should be kept in groups. The water temperature can be between 24 and 30°C.

For our customers: the fish have code 222134 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Pelvicachromis kribensis “Nyété” (formerly P. taeniatus “Nyété”)

31. October 2025

The city of Niété is located in the southern part of Cameroon and is part of the Océan department in the South Province. It is traversed by the Nyété River, which is a tributary of the Lobé River. The beautiful Pelvicachromis kribensis occurs there in a special color variant known in the hobby as “Nyété.” It looks very similar to the “Lobé” variant. The males of both species can be distinguished by the fact that the ‘Lobé’ males have no spots on their tail fin, in contrast to the “Nyété,” which are magnificently decorated in this respect; “Nyété” usually have 3-5 golden-rimmed eye spots in the upper part of the tail fin. This characteristic is inherited, making it a reliable distinguishing feature between “Nyété” and “Lobé.” 

Until a few years ago, all „emerald cichlids“ were grouped into a single species, Pelvicachromis taeniatus. Currently, three species are distinguished within this narrower family complex, namely P. taeniatus (Nigeria), P. kribensis (Cameroon), and P. drachenfelsi (Cameroon, formerly P. taeniatus “Wouri”).

This species should be kept under subdued lighting, otherwise the fish often become shy and pale. Soft, slightly acidic water best suits their needs. They will eat any standard ornamental fish food. The water temperature should mainly be in the range of 22-26°C; temperatures that are too high are less favorable for P. kribensis than the lower temperature range. It is important that at least part of the substrate consists of fine sand, which the fish like to chew on. Good water hygiene is crucial for the successful care of these fish, which is most easily achieved by regular and generous partial water changes. If this is neglected, P. kribensis quickly develop bacterial infections, which are usually incurable.

All Pelvicachromis have a mother-father family, in which the more colorful female is responsible for caring for the eggs laid in a cave and the newly hatched young. During this time, the male only defends the wider area around the spawning cave. When the young leave the cave, the mother and father join forces and raise the brood together. 

For our customers: the animals have code 562512 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Macropodus ocellatus

31. October 2025

The roundtail or Chinese paradise fish (Macropodus ocellatus, formerly M. chinensis) is a fish for connoisseurs and experts. For connoisseurs because it is extremely inconspicuous in its plain plumage – i.e. as a rule in the dealer’s tank. Those who are not familiar with it will therefore usually not buy it. But connoisseurs know: in their breeding plumage, the males of this species are truly wonderfully colored!

M. ocellatus is for experts because, as a fish from the subtropics (native to parts of China, Japan, and Korea), it must be kept in a seasonal rhythm. If this is not observed, the animals will not become in the mood to spawn, will remain pale, and their immune systems will be so severely compromised that they will sooner or later succumb to bacterial infections.

That is why an outdoor container—which can be an aquarium, a mortar tub, a small pond, or similar—is the ideal habitat for this species, which can become about 6-7 cm long in males and only 4-5 cm long in females. However, M. ocellatus is not truly winter-hardy in our latitudes. During the coldest time of the year, you must therefore ensure that the container either remains frost-free or that the fish are housed in an unheated but frost-free room during the frost period.

We usually receive our Chinese paradise fish in the fall from German outdoor keeping. Often we are given the location where they were initially found, but often we are not. The animals currently in our stock are such “nameless” ones. They are very strong, healthy fish 3-4 cm long, i.e., just reached sexual maturity.

For our customers: the animals have code 425402 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Saxatilia sveni (formerly: Crenicichla sveni)

31. October 2025

From Colombia (Rio Meta basin), we have obtained Saxatilia sveni, which is very rarely imported, together with Crenicichla (Batrachops) sp. “Belly Crawler” ( = C. sp. aff. sedentaria), which also occurs there. This representative of the former Crenicichla saxatilis group, which is currently grouped in a separate genus Saxatilia, grows to a considerable size, 25-30 cm. Our specimens are therefore still considered juveniles. However, they are already quarrelsome, which is why relatively large aquariums with numerous hiding places should be provided.

For our customers: the animals have codes 673533 (7-9 cm) and 673534 (10-12 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Crenicichla (Batrachops) sp. “Belly Crawler”

31. October 2025

The genus Crenicichla was once the largest of all cichlid genera, with 139 scientifically described species, 93 of which are generally recognized as valid species. In addition, there are a large number of species that are already known to aquarists but have not yet been scientifically studied. The genus has since been subdivided (see https://www.aquariumglaser.de/en/25-perchlike-fishes/the-crenicichla-have-been-reclassified/). The “Belly Crawler” therefore belongs to the subgenus Batrachops, which currently includes nine accepted species.

The “Belly Crawler” is a species from fast-flowing areas in the Rio Meta basin in Colombia that has not yet been scientifically recorded. As with so many fast-flowing cichlids, the Belly Crawler’s swim bladder is greatly reduced, making it impossible for the fish to float in open water. But they don’t need to.

Scientifically speaking, the Belly Crawler is closely related to Crenicichla (Batrachops) sedentaria from Peru, which swims normally but looks similar, and C. (B.) geayi from the Orinoco basin in Colombia and Venezuela. The latter lives close to the bottom but can still swim normally.

Crenicichla (B.) sp. “Belly Crawler” grows to a length of approx. 23 cm (males) and 18 cm (females). The sexes can be easily distinguished by the coloration of the dorsal fin, where the female has a round spot that the male lacks. Like almost all Crenicichla, the species can be characterized as relatively quarrelsome, but fighting is usually limited to impressive threats with wide-open mouths and lowered gills. The species is – typical for Crenicichla – a cave breeder with a parental family.

For our customers: the fish have codes 672613 (7-9 cm) and 672614 (10-12 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Hoplisoma sp. aff. concolor Rio Tomo CW217

24. October 2025

We consider the import of this beautiful new Hoplisoma to be sensational. According to the supplier, it comes from a small tributary of the Rio Tomo in eastern Colombia. The fishermen refer to this tributary as Cano Negro. The water is described as “crystal clear.” The Rio Tomo itself is a tributary of the Orinoco, approximately 650 km long. CW217 is the only armored catfish in the Cano Negro; there are no H. concolor there. We would like to take this opportunity to express our sincere thanks to our supplier for this information!

The new Hoplisoma “Rio Tomo” is undoubtedly a close relative of Hoplisoma concolor (see https://www.aquariumglaser.de/en/fisharchive/hoplisoma-concolor-2/). Ian Fuller (www.corydorasworld.com) assigned the code number CW217 to this strikingly colored fish. It should be noted that despite the physical similarity between CW217 and H. concolor, fish with this coloration never occur among “normal” H. concolor. CW217 is therefore not a color variant in the usual sense, as color variants are always found sporadically in populations of normally colored animals. According to most common species concepts, CW217 would be considered a subspecies (i.e., a geographically isolated population of a species that is, however, consistent in its characteristics) or, according to the so-called phylogenetic species concept, a separate species.

It is hoped that breeding these magnificent fish will be successful. The coloration of the young fish would also provide important clues as to their species affiliation. We know from other twin species (e.g., Osteogaster rabauti and O. zygata) that they are difficult to distinguish as adults, but that the young look completely different. For the time being, however, CW217 is only rarely available as a wild catch and in small numbers. The sexes are quite easy to distinguish. Males have long, pointed pelvic fins, while those of females are comparatively short and rounded. In addition, males often develop long dorsal fins (which, unfortunately, does not mean that all fish with short dorsal fins are females). All pictures in this post show the same pair from our first import. We have just imported a few more specimens and will provide more pictures as soon as possible.

For our customers: the fish have code 226015 on our stock list; the animals currently imported are still in quarantine but will be available on the stock list shortly. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Phenacogaster cf. capitulata

24. October 2025

Currently (September 2025), 28 species are assigned to this genus. The genus was established in 1907 by Eigenmann for the species Tetragonopterus pectinatus, described in 1870 by Cope from Peru (Pebas). Cope’s description was not accompanied by any illustration, so Fowler drew the holotype in 1907, which he classified in the genus Astyanax. Based on this drawing, it would be difficult to recognize a Phenacogaster; no wonder, then, that Steindachner fabricated two synonyms for P. pectinata in 1876 and 1882: Tetragonopterus tabatingae and T. bairdii. That was it for the 19th century.

The characin specialist Eigenmann described two species in 1909 and three more in 1911, while Norman (1934), Ahl (1936), and Fowler (1941) each described one species. Thus, by the middle of the 20th century, nine species were known, although this is a simplified representation, as not all of them were classified under Phenacogaster. Conversely, the fish described by Fowler in 1911 as Phenacogaster bondi is now classified as Gymnocorymbus, which is undoubtedly correct.

Then there was a long period of silence surrounding this group of tetras. It was not until 1995 that another species description followed, together with a new diagnosis of the genus. Brazilian ichthyologist Zilda Margarete Seixas de Lucena, already senior author of the 1995 paper, discovered these small tetras for herself and began researching them. The result is impressive. One of the species described in 2023, P. lucenae, was named in honor of Lucena and is the 15th new species since 1995! In terms of color, Phenacogaster are certainly no revelation. Most are small, transparent fish, usually with a shoulder spot, often with a tail root spot. They look very, very similar. Anyone who wants to delve into the finer points of species differentiation should start with the 2010 work “Descrição de nove espécies novas de Phenacogaster (Ostariophysi: Characiformes: Characidae) e comentários sobre as demais espécies do gênero” by Lucena & Malabarba (free download here: https://www.scielo.br/j/zool/a/47FyqVP45DrQ3wNV9Jwqt3k/?lang=pt), which discusses all species recorded to date and provides an identification key.

We have now been able to import a previously unknown Phenacogaster species from Peru for the first time. It should be clear that, based on the above list, an exact identification is complicated, as most newly described species are only known from preserved material. But our little newcomer—the animals are about 3 cm long (including the tail fin)—has no shoulder spot, no tail root spot, and comes from Peru. That narrows down the selection. We are probably looking at Phenacogaster capitulata, which was described in 2010 from the Neshuya River basin (part of the Rio Ucayali basin).

When in mating mood, the presumed males develop pretty orange fins with a white tip on the dorsal fin. This makes them vaguely reminiscent of the hummingbird tetra (Trochilocharax ornatus) in color, but they are considerably paler. The neon colors in some pictures are a result of the flash; to the naked eye, the fish are mainly transparent. They are peaceful animals that are best kept in a dimly lit aquarium with dark substrate. Their large eyes indicate that these fish do not like bright light. In terms of care and food, the animals have proven to be completely undemanding in our experience.

For our customers: the animals have code 278312 on our stock list. Please note that we only supply wholesale.

Text & photos: Frank Schäfer

Hyphessobrycon acaciae

24. October 2025

Imagine you have a first import and don’t even realize it! That’s what’s happening to us right now with a tetra. We received some very beautiful, large Hemigrammus coeruleus from Colombia. At least, that’s what we thought. By chance, Peter and Martin Hoffmann, from whom we often and gladly receive rare tetra offspring, needed a few H. coeruleus. Some time later, they asked where they came from. When we answered (Colombia), they said: Flavio is right again: they are Hyphessobrycon acaciae. Flavio refers to Flavio Lima, the tetra specialist from Brazil (Universidade Estadual de Campinas). The two had asked him about the identification of the fish, as they had noticed some differences from the usual coeruleus. 

With the naked eye, it is almost impossible to tell the difference between freshly imported Hemigrammus coeruleus and Hyphessobrycon acaciae, even though they are classified in two different genera. Technically speaking, the only difference between the genera Hemigrammus and Hyphessobrycon is that the base of the tail fin is unscaled in Hyphessobrycon, but scaled in Hemigrammus. This is not noticeable in living fish underwater. It has been known for decades that four of the main groups of South American small characins (the genus pairs Hemigrammus/Hyphessobrycon and Moenkhausia/Astyanax) are artificially classified and do not represent a natural relationship. But the work involved is very lengthy and complex, and it will certainly take quite some time before we really understand it.

For us, this means that we will now always have to carry out a special examination when Hemigrammus coeruleus from Colombia arrive. Using a powerful magnifying glass, we have to check the tail fin for the characteristic scaling, as the subtle differences in coloration are not visible in freshly imported animals that have not yet acclimatized. In terms of general care requirements, the two species do not differ. Both species are peaceful schooling fish that can reach a total length of 5-6 cm (including the tail fin). For H. coeruleus, see here: https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hemigrammus-coeruleus-4/

Text & photos: Frank Schäfer

Lugubria sp. Xingu1 (formerly: Crenicichla)

24. October 2025

In the 1990s, when Brazil’s large river cichlids experienced something of a boom, four species from the former collective genus Crenicichla also arrived in Europe for the first time. Due to the lack of a scientific name, they were designated Crenicichla sp. Xingu I – IV. All four grow to a considerable size for ornamental fish, reaching lengths of 30-40 cm, and are robust animals that can assert themselves. Very large aquariums are therefore a basic requirement for keeping these animals. They were banned from export for a long time, but Brazil has now lifted the ban. 

Strangely enough, Lugubria sp. Xingu I has not yet been scientifically studied. The young fish up to 5 cm in length are bright red, then they turn orange, which led to the nickname “French fries” for the fish. Adult specimens look completely different; the males are then brass yellow with vertical lines, the females gray-green with a bright red band in the middle of their bodies. At water temperatures above 30°C, when they are in breeding mood, the females look absolutely magnificent, with the entire middle of their bodies glowing coral red and their dorsal fins having a dazzling white edge, while their heads and tail stems are coal black.

We have young fish in our stock that are distinctly schooling fish. When kept in a school, they sometimes retain their beautiful coloration up to a length of 20 cm. Once they reach this size, the keeper must be careful! During “puberty,” before they become sexually active, these fish are extremely incompatible with each other! Only when the sexes are clearly recognizable can one attempt to pair them up. However, the small number of reported breedings —like all Lugubria species, these animals are cave breeders with a parental family—shows that this is rarely successful.

For our customers: L. sp. Xingu I/Orange has code 671801 (5-7 cm) and 671802 (6-8 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Heterandria formosa

24. October 2025

In old aquarium books, you can still read that the males of the Least Killifish (Heterandria formosa) could claim the title of “smallest fish in the world.” They grow to a maximum length of only about 2 cm, which is significantly smaller than the females, which grow to a length of up to 3.5 cm. But nowadays, 2 cm is no longer really competitive when it comes to records for small fish. With such lengths, you can hardly make it into the top 100!

There has been much speculation about what kind of fish is the smallest in the world. It is also not easy to come up with an objective method to find out. Fish grow throughout their lives. This makes it fundamentally difficult to provide reliable size data for fish. As with most livebearers, Least Killifish have both small and large males. This is genetically determined in these animals. In aquarium literature, the total length, i.e., including fins, is usually given. In extreme cases, this can be very misleading, as many fish species have elongated fin rays, such as the swordtail. A male with a sword as long as its body is not uncommon, but specifying the total length, i.e., from the tip of the snout to the end of the sword, as a measure of size makes little sense.

Be that as it may, we have just received a nice number of Least Killifish, including real dwarf males and also really large females. Most specimens are somewhere in between in terms of size.

The females of the Least Killifish only give birth to 1-2 young per day during a breeding period, but this continues over several days. They should therefore not be placed in spawning boxes, but in densely planted, small extra aquariums, from which the young are collected daily and transferred to a rearing aquarium.

The natural distribution of Least Killifish is in the eastern part of the United States. The climate there is not tropical, but subtropical. This should be taken into account when caring for them and the fish should not be kept too warm all year round. Ideally, they should be kept in tubs in the garden or on the balcony during the summer months. 

For our customers: the animals have code 421482 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Lentipes dimetrodon

17. October 2025

This dwarf goby, a relative of the of neon gobies (Stiphodon), was scientifically described in 1999. To date, the species is only known from coastal rivers in western New Guinea (Irian Jaya). However, since it undergoes its juvenile development in the sea, like all sicydiine gobies, it is more than likely that it is much more widespread.

The species Lentipes dimetrodon was described on the basis of six specimens, 5 males and 1 female. The largest male was 23.5 mm long, the female 19 mm (both measurements without tail fin). Unfortunately, the live coloration of the female remains unknown. Our animals are therefore probably fully grown (approx. 25-30 mm with tail fin). When you look into the holding tank, the jet-black little guys with bright blue-white fin edges immediately catch the eye. With their fins spread, they repeatedly rise into the free water column, impressing their conspecifics. 

A surprise awaited us in the photo tank. Suddenly, the little creatures developed a broad yellowish to salmon-colored zone in the middle of their bodies. Sometimes they are black, sometimes gray-brown in color. It is great fun to watch these lively aufwuchs eaters. Photographing them is less enjoyable, because these little creatures move at lightning speed and it is incredibly difficult to get a sharp photo of a swimming specimen with spread fins in front of the desired background.

Regardless, because these fish are very rarely available in the trade, it is really worth trying to breed them. Rearing saltwater fish is no longer an insurmountable problem. Of course, this would require being able to identify the females of L. dimetrodon. Unfortunately, we cannot do this…

For our customers: the animals have code 423622 on our stock list. Please note that we only supply wholesalers.

Text & photos: Frank Schäfer

Glossolepis dorityi

17. October 2025

We have once again received offspring of this beautiful rainbow fish. For basic information, please refer to this post: https://www.aquariumglaser.de/en/17-rainbow-fishes-and-co/glossolepis_dorityi_lake_nenggwambu__en/

Unfortunately, it is quite likely that Glossolepis dorityi, which was only scientifically described in 2001, is already extinct in the wild. We quote here from the entry in the International Red List (IUCN): “This species is known only from Lake Nenggwambu (Lake Kali Biru), a small (4-5 hectares) floodplain lake in the Grime River system, about 60 km west of the Papua provincial capital of Jayapura, Indonesia, and nearby Lake Tum (erroneously called Lake Jaigum) (G.R. Allen pers. comm. 2019). Other searches have not found populations elsewhere, but it is possible it occurs in other lakes.” 

The population of Tum Lake ( = Jaigum Lake) could no longer be found in 2009, as Johannes Graf, an experienced traveler and expert on rainbow fish, discovered. In Lake Nenggwambu, the once crystal-clear water is now a murky broth, and all the underwater plants that used to grow there in abundance have disappeared. The cause lies in carp and tilapia that were released for food purposes.

The populations from both lakes (there are no color differences between the two) in human care still appear to be stable. You can help save this species from extinction by buying such fish for your aquarium. Only if breeders of the species can find homes for their offspring will they continue to breed them!

For our customers: the animals have code 417133 on our stock list. Please note that we only supply wholesale.

Source:

Allen, G.R., Hammer, M. & Unmack, P. 2020. Glossolepis dorityi. The IUCN Red List of Threatened Species 2020: e.T161080437A161080455. https://dx.doi.org/10.2305/IUCN.UK.2020-3.RLTS.T161080437A161080455.en. Accessed on 09 September 2025

Text & photos: Frank Schäfer

Poecilia wingei Endler Guppy Campoma No 46

17. October 2025

It is not without reason that guppys are among the most popular ornamental fish in the world, ranking high in the top ten. The play of colors is almost endless. This applies to the “classic” guppy Poecilia reticulata as well as its slightly smaller cousin P. wingei, the Endler guppy, and the countless hybrids that have been and are being bred between these species.

The wild forms of the classic guppy are rarely kept in aquariums, but wild forms of the Endler’s guppy are extremely popular. In order to designate them in a reasonably uniform manner, they have been numbered, although there is no binding reference register. The web pages on which the numbers were originally assigned no longer exist. This means that it is not possible to research them. So we do not know whether what we have now received as No.46 and are offering under this designation is identical to the original No.46. But that doesn’t matter, because we have pictures of it.

Incidentally, these “Campoma numbers” do not refer to different locations where they were found. Most of them were caught either together or in close proximity to each other. In nature, Campoma guppys are just as variable in color as classic guppies. Hardly any two males look exactly alike. However, selective breeding can be used to quickly establish the characteristics that are particularly appealing. As a result, the Campoma No.46 now look fairly uniform. However, if they are allowed to reproduce without strict selection, a wide variety of color variations will gradually appear. This is normal and does not indicate that they are hybrids.

For our customers: the fish have code 419018 on our stock list. Please note that we only supply wholesale.

Text & photos: Frank Schäfer

Bunocephalus coracoideus

16. October 2025

Banjo catfish (Bunocephalus) are extremely common in nature. That’s why we always have them in stock. We usually refer to these animals as Bunocephalus coracoideus, which may be correct in many cases. But when you look at such a swarm of banjo catfish, you notice that there are always other species mixed in. As a rule, it is not possible to identify them with reasonable effort, let alone sort them, but it is extremely exciting to raise and observe a group of perhaps 20 of these animals in an aquarium. Then you notice how variable these animals are in coloration, that there are clear differences in anatomy (especially the bone ridges along the middle of the back in front of the dorsal fin), and also that there are species that prefer to burrow more than others.

As mentioned, Bunocephalus are usually not identified in more detail in the trade and are marketed under the name B. coracoideus. It gets tricky when Bunocephalus that are visually distinguishable from the “mainstream” are imported; we try to identify these as accurately as possible, of course. That is why we will briefly describe here what we currently understand to be the “real” B. coracoideus.

The species name “coracoideus” refers to a very characteristic feature of this species, the coracoid bones. These are bony processes that, in this case, support the pectoral fins. Since these bony processes lie directly under the skin, they are also clearly visible in living animals. According to current knowledge, B. coracoideus has the most pronounced coracoid bones in the genus Bunocephalus, which currently comprises 14 species. The ventral parts of the processes extend almost to the base of the ventral fins. A second feature that characterizes the species B. coracoideus very well are the bony protuberances along the middle of the head. Three distinct larger elevations can be seen here, and a small one immediately in front of the dorsal fin. This combination of features allows for a fairly reliable identification in most cases. Colouring is not such a good characteristic, as it is very variable. However, it almost always consists of a front part covering the head that differs from the colouring of the tail. A well-known synonym for B. coracoideus is B. bicolor; “bicolor” means “two-colored”.

B. coracoideus is widespread throughout the Amazon region and can therefore come to us from practically all ornamental fish exporting countries that have access to the Amazon. Currently, for example, we have some very beautiful specimens from Colombia in stock. However, genetic studies have shown that different populations of B. coracoideus, which are visually indistinguishable from one another, differ so significantly in terms of their genetic makeup that they should actually be considered different species. This is important to know in practice, especially when attempting to breed them. If you want to breed Bunocephalus, which is entirely possible, although not commonly practiced, you should always assemble your breeding stock from animals from the same import to avoid producing unwanted hybrids.

For our customers: B. coracoideus has code 212901 (2-3 cm) to 212907 (10-12 cm) on our stock list, depending on size. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Garra qiaojiensis

10. October 2025

Many good aquarium fish have come to us from the extremely species-rich genus Garra. The “doctor fish” Garra rufa (https://www.aquariumglaser.de/en/fisharchive/garra-rufa-2/), Garra flavatra (https://www.aquariumglaser.de/en/08-carp-like-fishes-2-barbs-minnows-carps-goldfish-etc/garra_flavatra_en/) is very pretty, and Garra panitvongi (https://www.aquariumglaser.de/en/fisharchive/garra-panitvongi-sp-red-tail-2/) is bizarre and beautiful.

Now we received two specimens of a Garra species as samples, whose beauty took our breath away. This is Garra qiaojiensis, which occurs only very locally in the Irrawaddy system of China and Burma. Our fish come from the Putao region in Burma. They are approximately 9 cm long. Based on certain characteristics (one specimen has a red spot on its shoulder, which the other fish does not have, there are also differences in the coloration of the pelvic fins, and one fish appears to be slimmer than the other), we believe that they are a pair.

What took our breath away next, however, was the price. Our supplier only had a small number of animals in stock, all of which we have now imported.

For our customers: the animals have codes 416383 (8-10 cm) and 416384 (10-12 cm) on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Spinipterus moijiri

10. October 2025

The discovery of a new genus of driftwood catfish—Spinipterus—is quite sensational. In 2011, the first species of the newly described genus (S. acsi) was described and the new genus was established for it. In 2019, the second species (S. moijiri) was added, which is significantly more attractive in appearance and displays a beautiful jaguar pattern when fully grown. In younger animals, the spots are still full, but later they become more ring-shaped. S. acsi grows to about 8 cm, S. moijiri to about 10 cm in length. S. acsi occurs in the upper Amazon basin (Peru, Brazil), S. moijiri in Peru (Rio Nanay) and Brazil (Rio Purus and Rio Japura). We obtained our animals from Peru.

They are very peaceful, strictly nocturnal catfish, which can be compared to Tatia from an aquaristic point of view. Both Spinipterus species have been successfully bred on several occasions. It has been found that these fish are best kept in groups. Unlike most Tatia species, they do not usually care for their young, but simply scatter the eggs freely in the tank. However, there have been isolated observations of females guarding the eggs in a tube.

As with all driftwood catfish, the sexes can be easily distinguished once they reach sexual maturity by the different shapes of their anal fins. The most important care measure for Spinipterus is certainly feeding. On the one hand, care must be taken to ensure that the animals get something to eat; this means that, at least in the early stages of acclimatisation, they may need to be fed even after the lights have been turned off. Conversely, once the fish have settled in and start appearing for feeding during the day, care must be taken to ensure that they do not become overweight. They are good and efficient eaters! They will happily eat any commercially available ornamental fish food. In nature, insects and their larvae are probably their main food source. Water hardness and pH are irrelevant, the water temperature can be within the usual range (24 to 28°C), and it does not matter if it is slightly higher or lower at times.

For our customers: the animals have code 295232 on our stock list. Please note that we only supply wholesalers.

Text & photos: Frank Schäfer

Nannostomus erythrurus

10. October 2025

The three-banded pencilfish, Nannostomus trifasciatus, is one of the most popular ornamental fish. It combines numerous characteristics that make it desirable: beautiful coloration, peaceful nature, small size, and easy feeding. However, few people know that the name “Nannostomus trifasciatus” actually refers to several species. The “real” N. trifasciatus is relatively rare in stores. It comes from the area around Manaus in Brazil and Tabatinga/Leticia in the border triangle of Peru, Colombia, and Brazil. Its distinguishing feature: above the broad, dark longitudinal band, there is an additional narrow red stripe. Unfortunately, this stripe is easily overexposed and is therefore often difficult to see in photographs.

The twin species, N. erythrurus, is very widespread. It was first described from Guyana, but is also found in Peru and in the lower reaches of the Amazon in Brazil. The red stripe mentioned above is always absent here; only a red shoulder spot is often found. The similarity between N. erythrurus and N. trifasciatus is so great that until 2013, N. erythrurus was usually considered a synonym of N. trifasciatus; N. erythrurus was described as early as 1909.

From time to time, we receive such beautiful N. erythrurus from Peru and Brazil that we also distinguish them as a special species. Otherwise, no distinction is usually made between the two species in the trade.

N. erythrurus and N. trifasciatus do not differ in terms of the positive characteristics listed above. Both are ideal aquarium fish.

For our customers: N. erythrurus has code 272013, N. trifasciatus code 272301-272306 (depending on size). Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Sicyopterus microcephalus (incorrectly imported as S. longifilis)

10. October 2025

The genus Sicyopterus comprises the largest species of the increasingly popular sicydiine gobies, which include Stiphodon, Sicyopus, Sicydium, Lentipes, and others. All of these gobies undergo their larval development in the sea, while the adults live in pure freshwater and lay their eggs there. Since the larvae have hardly any yolk reserves, they must be carried relatively quickly into the sea by the current. This is why sicydiine gobies are only found in flowing waters and not very far from the sea. Depending on which ocean current the larvae are carried into, they may end up in freshwater far from their birthplace. This explains the sometimes huge distribution areas of many species.

 

Unfortunately, the detailed classification of the genus Sicyopterus is poorly understood. The approximately 27 to 33 currently recognized species (depending on the author) all look quite similar and are all very variable in color. Depending on their mood, age, and sex, they can have very different coloration. This makes them difficult to identify. It was not until 2018, for example, that Sicyopterus longifilis was first identified in Japan, a country that has been very well studied ichthyologically. Until then, only two other species of the genus were known from there, namely S. lagocephalus and S. japonicus. In clarifying the identity of the species new to Japan, the researchers (Maeda & Saeki, 2018) discovered that S. brevis, described in 1912 at the same time as S. longifilis from Ceram, is in fact only the female of S. longifilis (male).

The most important distinguishing feature of S. longifilis for us aquarists is the combination of very long, free dorsal fin rays (at least in males; the dorsal fin rays of females are also free and elongated, but not quite as long) and the absence of a notch in the middle of the upper lip; the latter is best seen when the animal is suctioned to the front glass. The animals we imported under the name S. longifilis have long, extended dorsal fin rays, but they also have another lip feature: papillae on the upper lip. These are typical for S. microcephalus, but are absent in S. longifilis. Therefore, the pictures shown here are most likely of S. microcephalus and not S. longifilis.

Sicyopterus should be kept in aquariums that resemble a stream, i.e., with sand, gravel, and rubble areas. A few roots won’t hurt, but planting should be kept to a minimum. The fish appreciate a strong current. They often burrow into the ground, especially under flat stones, where they also spawn. Sicyopterus are easy to feed. Naturally herbivorous, they enjoy all kinds of dry and frozen food, as long as it is not too coarse. Hardness and pH value are insignificant; any tap water suitable for drinking is also suitable for the care and breeding of Sicyopterus. The water temperature can be between 20 and 28°C. Sicyopterus are generally peaceful fish, and intraspecific squabbles are always harmless in nature, at least in our experience. The species grows to a length of approx. 10 cm (including tail fin).

For our customers: the fish have code 455163 (5-7 cm) on our stock list. Please note that we only supply wholesale customers.

Literature:

Maeda, K. & T. Saeki (2018): Revision of species in Sicyopterus (Gobiidae: Sicydiinae) described by de Beaufort (1912), with a first record of Sicyopterus longifilis from Japan. Species Diversity v. 23: 253-262.

Text & photos: Frank Schäfer

Aspidoras raimundi C125 Red

12. September 2025

The genus Aspidoras has recently undergone a revision, resulting in several regroupings. Among other things, the species A. menezesi and A. spilotus, well known at least by name in the hobby, have been synonymized with A. raimundi. Cory-catfish enthusiasts agree that C125 and CW119 also belong here. More information on the wild type of A. raimundi can be found here: https://www.aquariumglaser.de/en/10-catfishes/aspidoras-raimundi-ceara-2/

According to our breeder, who first supplied us with these animals 11 years ago, the red form with red eyes appeared spontaneously among his offspring of wild-colored C125. Their exact origin was/is still unclear to us; we only know that they came from Brazil. As you can see, the red strain has been well stabilized. The final size of these beautiful and peaceful armored catfish is 4-4.5 cm. The usual care recommendations for armored catfish apply.

For our customers: the animals have code 208582 on our stock list. Please note that we only supply wholesale.

Literature:

Tencatt, LFC, Britto, MR, Isbrücker, IJH & CS Pavanelli (2022): Taxonomy of the armored catfish genus Aspidoras (Siluriformes: Callichthyidae) revisited, with the description of a new species. Neotrop Ichthyol. 2022; 20(3):e220040. https://doi.org/10.1590/1982-0224-2022-0040 

Text & photos: Frank Schäfer

Hoplisoma sp. CW127 BRED

12. September 2025

One of the most magnificent armored catfish to become available in recent years is undoubtedly the CW127 from the Rio Jamanxim. For more information, see https://www.aquariumglaser.de/en/fisharchive/corydoras-sp-aff-parallelus-cw127-4/

We now have German captive-bred specimens of these magnificent animals in stock for the first time.

For our customers: the animals have code 240262 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Apistogramma eunotus “Orange Tail”

12. September 2025

In this day and age, when absurd debates are being held about banning private animal husbandry as far as possible (“positive list”), we must always remember the great successes that have been achieved with many fish groups thanks to the aquarium hobby. The genus Apistogramma is a prime example of this. Until 1977, 31 species were known, but only 20 of these were valid. Today, almost 100 valid species are known (94 to be precise), and there are still a few that are already known in the hobby but have not yet been scientifically described. This enormous increase in knowledge would have been unthinkable without the interest of aquarists in these fish. If we now consider that knowledge of species is the absolute prerequisite for every conceivable form of species protection, the example of Apistogramma clearly shows that wild imports do not threaten species, but on the contrary form the basis for their protection.

The “first wave” of Apistogramma discoveries in the early 1980s also included a species from Peru that became known in the hobby as the “orange-tailed Apistogramma”: A. eunotus. This species, which is quite large by Apistogramma standards—males can easily reach 8.5 cm in length—originates from lowland rivers in Peru and neighboring areas of Colombia. Like almost all Apistogramma, the males are polychromatic, meaning that males of different colors can be found at the same location. However, the orange-tailed color morph, which is considered particularly attractive in the hobby, is relatively rare. Very often, entire imports of A. eunotus do not contain any males with colored tail fins. However, we have just received an import from Peru with a high proportion of such fish.

Apistogramma eunotus is special in that it not only dislikes the highly acidic water values (pH below 5.5) required for breeding in many species of the genus, but actually avoids them. A. eunotus also does not appreciate high concentrations of humic substances, which are almost essential for many Apistogramma species. Breeding this typical cave spawner with a mother-father family is also successful in slightly alkaline water of medium hardness. In nature, very different values have been found in A. eunotus biotopes, but never very acidic water. The water temperature in the aquarium should be between 23 and 27°C; in the wild, values between 18 and 31°C have been measured. Like all Apistogramma species, this one also needs places with fine sandy soil to chew through. Feeding is unproblematic; any commercially available ornamental fish food of a suitable size is readily accepted.

For our customers: the animals have code 619002 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Hemiodus semitaeniatus

12. September 2025

With 23 species, the genus Hemiodus is quite species-rich. The majority of species grow to a length of 15-20 cm, with the largest reaching around 30 cm. Previously, three genera were distinguished (Hemiodus, Hemiodopsis, and Pterohemiodus). However, the characteristics considered to be differences between the genera proved to be insufficiently relevant. Therefore, all three were merged back into one genus – Hemiodus. 

Hemiodus are sensitive to stress. Their capture, acclimatization, and transport can therefore only be successful with the utmost care. This is the reason why these fish are relatively rare in the trade. All species observed in aquariums to date exhibit a slanted swimming behavior. These elegant animals should always be kept in schools of at least eight, as individual fish can be very nervous. Another basic requirement is a large aquarium with plenty of free swimming space. Hemiodus are peaceful towards each other and towards fish of other species. There have been no reports of breeding in aquariums. Hemiodus can be described as undemanding in terms of water values (pH and hardness) and food (any standard ornamental fish food of a suitable size is readily accepted), but the water should be clear and rich in oxygen. A temperature between 24 and 28°C is probably optimal for all species.

The only species of the genus that is offered relatively regularly is Hemiodus gracilis. It has a characteristic pattern. A strong black longitudinal band begins approximately in the middle of the body and continues into the lower half of the caudal fin. Below this black band, the edge of the tail fin of H. gracilis is deep red – very attractive! H. semitaeniatus and H. goeldii are almost identical in color, but in both species the lower edge of the tail fin is white rather than red. H. semitaeniatus has significantly more scales in the longitudinal row than H. gracilis and H. goeldii (these have only about 50 fairly large scales in the longitudinal row, H. semitaeniatus has over 50, making the scales significantly smaller in relation to the body). You can easily shorten the scale counting by only counting the scales along the edge of the back before the base of the dorsal fin. Here, H. semitaeniatus has well over 20 scales, while H. goeldii has only 12.

We recently received „H. gracilis“ from Colombia, which unfortunately show no red in their tail fins. Closer investigation revealed that they are actually H. semitaeniatus. This species is widespread in South America: it has been reported in Brazil, Bolivia, Guyana, Colombia, Paraguay, Peru, and Venezuela. However, recent genetic studies on Hemiodus (Nogueira et al., 2020) suggest that this is more likely to be a species complex than a single species. The largest specimen of H. semitaeniatus measured to date was 20 cm long.

For our customers: the animals have code 258282 (4-6 cm) on our stock list. Please note that we only supply wholesale customers.

Literature:

Nogueira, A. F., C. Oliveira, F. Langeani & A. L. Netto-Ferreira (2020): Overlooked biodiversity of mitochondrial lineages in Hemiodus (Ostariophysi, Characiformes). Zoologica Scripta v. 50 (no. 3): 337-351.

Text & photos: Frank Schäfer

Pimelodus tetramerus

12. September 2025

The genus Pimelodus is quite species-rich, with 35 recognized species currently, and also very confusing due to a lack of recent revision. These South American catfish play only a minor role in aquariums. The only species regularly available in stores is Pimelodus pictus, the angel catfish, and P. ornatus is an expensive rarity sought after by specialists. Other species occasionally appear in small numbers in the trade, but are generally insignificant. With the species presented here, which we have occasionally been able to import from Venezuela or, as is currently the case, from Peru, the spectrum could be expanded by another species, as the animals are very attractive: Pimelodus tetramerus.

The species was described in 2006 from the Tocantins and Tapajos rivers in Brazil. Imports were made from the Rio Xingu, Venezuela, Colombia, and Peru. Grant (2021) suspects a species complex behind the various imports; although we do not rule out this possibility, the externally recognizable differences between animals from the various export areas are so minor that we do not distinguish between them. The size of the imported animals is usually around 6-9 cm; P. tetramerus grows to about 20 cm in length.

Unlike many other catfish, Pimelodus species are also active during the day. At least as juveniles, they are distinctly schooling fish, so you should always purchase 5-10 specimens at once. They are completely peaceful towards other fish, but smaller tank mates will of course be regarded as food. Pimelodus are as undemanding in terms of nutrition as they are in terms of water values, which is why even beginners can enjoy these beautiful fish. You just have to be careful with their extremely sharp fin spines. Both the pectoral fins and the dorsal fin have fin spines that are sharper than we have seen in almost any other fish species. It is therefore generally better to catch these catfish with a cup or similar, as there is a high risk of them becoming terribly entangled in any net.

For our customers: the animals have code 280113 on our stock list. Please note that we only supply wholesale.

Literature: 

Grant, S. (2021): Pims; Pimelodidae, Heptapteridae and Pseudopimelodidae Catfishes. Neuenstadt am Rübenberge, 220 pp.

Ribeiro, F. R. V. & C. A. S. de Lucena (2006): Nova espécie de Pimelodus (Siluriformes, Pimelodidae) dos rios Tapajós e Tocantins, Brasil. Iheringia, Série Zoologia (Porto Alegre) v. 96 (no. 3): 321-327.

Harttia punctata

5. September 2025

From the species-rich genus Harttia—currently divided into 28 species—hardly any ever find their way into our aquariums. The fish are relatively close relatives of the popular royal farlowellas (Sturisoma and Sturisomatichthys) and resemble them in many behaviors, but are considerably more demanding. Harttia need very clean, oxygen-rich, and warm water to thrive; in addition, fine food, such as the fish’s natural diet (algae and the microorganisms living in it), should make up the majority of their diet. Even minor care mistakes can be fatal for such fish. It is obvious that even catching and transporting them poses particular challenges. On the other hand, healthy animals have even been bred in aquariums.

Harttia punctata is one of two species found together in the Rio Tocantins in Brazil. The most important difference between the two species – the other being H. duriventris – lies in the shields on the abdomen. In H. duriventris, the entire belly is covered with bone plates, while in H. punctata, large parts of the belly are bare. Overall, however, it has been found that the pattern on the belly is quite variable within the species. H. punctata and H. duriventris hardly differ in color, but H. punctata has more numerous, more contrasting spots. In two randomly selected animals from our current import, the abdominal shields correspond to H. punctata. Since all the fish are very similar in color, we think that they all belong to the same species. However, we cannot rule out the possibility that some H. duriventris may be hiding among them.

Just like Sturisoma and Sturisomatichthys, Harttia are not cave breeders, but open breeders. The eggs are preferably laid on stones with a strong current flowing over the surface and guarded by the male until they hatch. Sexual differences seem to be limited to the fact that the males have a slightly wider head and a wider, spiked first pectoral fin ray. Rearing is broadly similar to that of royal farlowella.

All in all, Harttia punctata are fish for truly experienced aquarists looking for a challenge.

For our customers: the animals have code 255384 on our stock list. Please note that we only supply wholesale.

Literature:

Seidel, I. (2010): Ingos Harnischwelszucht. Tetra Verlag, Berlin-Velten, 272 pp

Text & photos: Frank Schäfer

Sternarchorhynchus mendesi

5. September 2025

The number of species in the genus Sternarchorhynchus has exploded in recent years. In 1994, only four species were known, but by 2006, the number had risen to ten, and today (2025), 32 species are recognized! This makes Sternarchorhynchus the most species-rich genus within the Apteronotidae family. 

With a shipment of Apteronotus macrostomus (in the hobby known as A. leptorhynchus, see https://www.aquariumglaser.de/en/11-gymnotiformes-knifefishes-of-the-new-world/apteronotus-leptorhynchus-a-macrostomus-2/) from Colombia, we also received a single specimen of a Sternarchorhynchus species. According to the latest revision of the genus by de Santana & Vari (2010), there are seven species of the genus in Colombia: S. gnomus, S. marreroi, S. mendesi, S. mormyrus, S. oxyrhynchus, S. roseni, and S. yepezi. There are hardly any color differences between the species. Almost all are monochromatic dark brown with a light eel stripe; only S. gnomus lacks the light dorsal stripe or has only a faint one. If one follows the identification key for the species from the Orinoco in the aforementioned work, the shape of the mouth initially leads to S. oxyrhynchus; however, for those of us who are not deeply familiar with the subject matter, this characteristic is somewhat deceptive because we do not have good means of comparison.

The remaining key leads to S. mendesi (distinct dorsal stripe, no scales on the back). S. oxyrhynchus has 212–242 fin rays in the anal fin, making it a very elongated fish, while S. mendesi has 174–182. The photographed animal has approximately 177 anal fin rays (without an X-ray, slight inaccuracies in counting are possible at the very front and very back, but these are not critical for species identification). So it’s official: we have successfully imported Sternarchorhynchus mendesi for the first time!

This is remarkable in that S. mendesi is currently known from only eight specimens, all of which were found in the Río San Juan and Río Guanipa river basins in northeastern Venezuela. Apteronotus macrostomus, on the other hand, is caught in the Rio Meta basin in Colombia for export as an ornamental fish.

The largest specimen of S. mendesi known to date was just over 20 cm long. The imported fish has proven to be easy to care for so far; its current length is about 15 cm. At the end of its body, it has a small regenerative tail; as is well known, knifefish have the very unusual ability to regenerate lost parts of their spine at the end of their body, provided that no vital internal organs are affected. The animal proved to be completely peaceful towards even small tank mates (three-quarter-sized guppies). Sternarchorhynchus can be easily fed with frozen and live food in the aquarium; tubifex and bloodworm are particularly popular. South American knifefish have generally proven to be very adaptable in terms of water parameters such as hardness and pH value. The animals are mainly crepuscular, but come out of hiding during the day when feeding. The animals are only moderately compatible with conspecifics, see https://www.aquariumglaser.de/en/11-gymnotiformes-knifefishes-of-the-new-world/sternrachorhynchus-from-peru/. Since Sternarchorhynchus have sharp teeth in their mouths, they can theoretically injure each other. When keeping several animals together, it is therefore important to pay close attention so that you can intervene in time if necessary.

For our customers: the animal has code 293984 on our stock list. Please note that we only supply wholesale customers.

Literature: 

de Santana, C. D. & R. P. Vari (2010): Electric fishes of the genus Sternarchorhynchus (Teleostei, Ostariophysi, Gymnotiformes); phylogenetic and revisionary studies. Zoological Journal of the Linnean Society v. 159 (no. 1): 223-371.

Text & photos: Frank Schäfer

Pseudocrenilabrus multicolor

5. September 2025

The longest-serving mouthbrooding cichlid in our aquariums is Pseudocrenilabrus multicolor. It was introduced to Germany from Egypt as early as 1902. The animals, which are usually 4-5 cm long—the maximum length given in the literature is 8 cm—have never died out in the hobby since then. It can even be assumed that these fish have been kept and bred in conservation breeding for over 100 years without “new blood,” i.e., without any new imports. Only recently has it become somewhat quiet around it. We are therefore very pleased to be able to offer it again.

P. multicolor cannot compete with the colorful mouthbrooding cichlids from Lake Malawi, even though it is very colorful. But its colors are iridescent and small, while its larger cousins are strikingly colorful. On the other hand, it is always a great pleasure to observe the brood care of this lively little animal. Unlike most Malawi cichlids, the mother P. multicolor keeps the young fish in her mouth for many days (about a week) after they are first released, in case of supposed danger and at night.

P. multicolor should be kept at temperatures between 20 and 28°C in well-planted tanks, which should also have some areas of bare sand. During the spawning season, the male builds a shallow pit and attracts the fairer sex by displaying his magnificent colors and surfing across the bottom with his tail fin, showing her the way to the love nest. They will eat any standard ornamental fish food of a suitable size, whether dry, frozen, or live food. Due to its relatively small size, P. multicolor does not need large aquariums, but the males should not be underestimated during the spawning season. Filled with hormones, they successfully take on significantly larger opponents, and harmless peaceful fish also have nothing to laugh about.

For our customers: the animals have code 566303 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Otocinclus cf. macrospilus = O. mangaba?

5. September 2025

The small sucker catfish of the genus Otocinclus are among the most popular “cleaners” in aquariums. They tirelessly clean all surfaces they can reach. Since they usually only grow to 3-4 cm, rarely up to 5 cm in length, and perform their cleaning activities very delicately, they do not damage even relatively delicate plants, but ensure that they look clean and fresh.

Unfortunately, most of the 20 currently accepted species look very similar to each other. In 1997, Scott A. Schaefer published a major revision of the genus, in which 15 species were distinguished. This revision was intensively discussed in aquarium circles, and attempts were made on its basis to finally assign the correct names to the species available in the hobby. The success was rather modest. The majority of Otocinclus traded still sail under the name “Otocinclus affinis,” although this inconspicuous species from southern South America is hardly ever found in stores. Most of the animals designated as such belong to the species O. vestitus.

A pretty and very hardy species has been imported from Brazil for decades. It is called “Otocinclus cf. macrospilus” because of the very large spot on its tail root. The word ‘macrospilus’ means “with a large spot.” The species Otocinclus macrospilus was scientifically described as early as 1942 and illustrated in a very good drawing. The specimens on which the description was based were found in the Rio Morona, upper Amazon basin, Loreto department in Peru. Although the animals imported from Brazil visually matched O. macrospilus well, the locations where they were found were very far apart. Research revealed that the Brazilian specimens are caught in the Rio Purus; at least some of them come from the political municipality of Lábrea, located on the Rio Purus. This prompted the addition of “cf.” (stands for ‘confer’ and means “compare with”) to express a certain reservation in the determination. Rightly so, as it now turns out. One of the recently newly described species—Otocinclus mangaba from the Rio Madeira basin—is much more similar to the Otocinclus from the Rio Purus. The Rio Purus and the Rio Madeira flow parallel to each other for long stretches toward the Amazon and are only about 200 km apart on average.

A feature that is rare in Otocinclus is typical of O. mangaba: the abdominal region between the large pectoral bone plates on the sides of the body is bare – just like in Otocinclus from the Rio Purus! The coloration of O. mangaba also corresponds very well to that of the animals from the Rio Purus. Some differences in detail are due to individual color variation, while others are mood-related. In the preserved holotype of O. mangaba, the large tail root spot appears to be divided into two parts, a front and a rear half. This is also the case in freshly imported animals, but this color feature largely disappears in well-acclimated animals.

Basically, it doesn’t matter which Otocinclus species you buy, as they are all excellent aquarium fish and outstanding cleaners. They should be kept in groups that are as large as possible, as they are social animals. And it is essential to ensure that they get enough food. Slices of vegetables (zucchini, potato, carrot, etc.) should always be available (replace daily, otherwise it will pollute the water), along with fine frozen food (cyclops, artemia, water fleas) and food tablets. This is the recipe for round and happy otos. Hardness and pH value are insignificant for these fish; any tap water suitable for drinking is suitable for their care. Males are smaller and slimmer, but there are no other differences between the sexes. Breeding is similar to that of armored catfish, i.e., the animals spawn in groups. Otocinclus do not care for their young.

For our customers: Otocinclus cf. macrospilus/O. mangaba have codes 274113-274116 on our stock list, depending on size. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Ivanacara bimaculata

29. August 2025

This cichlid was scientifically named and illustrated as early as 1912 under the name Nannacara bimaculata. However, it remained a phantom in the hobby. Its distribution area in Guyana (Potaro River) is considered one of the most difficult areas to travel to in South America. It was not until 1997 that Frans Vermeulen, together with Wim Suikers, was able to collect a few specimens and bring them back to the Netherlands. It became apparent that the species was very similar in behavior and appearance to I. adoketa, which at that time was still classified in the genus Nannacara. Consequently, the species was then incorporated into the genus Ivanacara, which was described in 2006.

To this day, this fish has remained a top rarity, as breeding it is just as challenging as breeding I. adoketa (see https://www.aquariumglaser.de/en/fisharchive/ivanacara-adoketa-nannacara-a-2/). Everything that has been said about I. adoketa also applies to I. bimaculata, which is why we refer to the corresponding entry at this point.

We are delighted to now be able to offer these beautiful cichlids as 3-4 cm long offspring. The young fish we currently have in stock already give an idea of how beautiful these fish will become. Even at this size, males and females are quite easy to distinguish by their color. Incidentally, according to the literature, males of I. bimaculata can grow to a maximum length of 13 cm and therefore no longer quite meet the definition of “dwarf cichlid” – by definition, this title is reserved for species with a maximum total length of 10 cm. Females, however, remain smaller. According to our breeders, I. bimaculata remains much smaller than stated in the literature – at least this strain. Males are said to be fully grown at a total length of about 6 cm; very old animals may still grow 1-2 cm.

For our customers: the animals have code 684062 on our stock list. Please note that we only supply wholesale customers.

Text & photos: Frank Schäfer

Synodontis sp. aff. nigriventris ZEBRA

29. August 2025

The upside-down catfish Synodontis nigriventris is the most popular species from the species-rich genus Synodontis. The comical behavior of these animals, which prefer to swim belly-up, is certainly the main reason for this. In addition, the species remains small, well under 10 cm. In fact, we have never seen animals larger than about 7 cm (including the tail fin). More information about the species can be found here: https://www.aquariumglaser.de/en/fisharchive/synodontis-nigriventris-4/

In addition to this species, we also occasionally have the “zebra” in stock. As far as we know, this species comes exclusively from the Lac Mai Ndombe area, a huge blackwater lake in central Congo. It differs from the “common” upside-down catfish in its extremely contrasting coloration, especially on the belly. The species name “nigriventris” means “with a black belly.” The belly of the common upside-down catfish is dark in color. If you look closely, you can see black dots on a dark background. In the “zebra,” however, the belly coloration consists of a complex marble pattern that is different for each individual fish. Overall, the pattern of the “Zebra” is reminiscent of the juvenile coloration of several Synodontis species. 

In terms of all care aspects and final size, the “Zebra” does not differ from the common upside-down catfish, except that it is perhaps even a little more social. It is almost impossible to photograph a single specimen when there are several in the aquarium.

For our customers: The animals have code 183413 on our stock list. Please note that we only supply wholesale.

Text & photos: Frank Schäfer

Tatia perugiae and Tatia cf. altae

29. August 2025

The driftwood catfish Tatia perugiae has become firmly established in the hobby. The species is small (4-6 cm), very pretty in color, and easy to breed in the aquarium. In addition, the animals are very peaceful and undemanding in terms of water composition and food. It is understandable that they usually only leave their hiding places to feed and then swim around busily. We source the species as offspring or from Peru. There are at least two color forms, one with relatively small and one with large dark spots (see collage of the two pictures on the right; all fish in this collage are sexually mature males). But overall, the species is highly variable in coloration, and each individual can be recognized by its personal spot pattern, which is as specific as a fingerprint.

Unfortunately, this species has already undergone several genus changes. It was first placed in Tatia, then in Centromochlus, then in Duringlanis, and now, in the most recent review by Luisa Maria Sarmento-Soares & Ronaldo Fernando Martins-Pinheiro (2020), back in Tatia. In the study by Calegari et al. (2019), which is only one year older, Duringlanis was still identified as a valid genus—in short, one should search for both genus names when compiling information on these fish.

In the same journal as Sarmento-Soares & Martins-Pinheiro, Henry W. Fowler described a very similar species from Colombia (Morelia, headwaters of the Rio Caqueta) as Centromochlus altae 75 years earlier. He wrote at the time that this species was very similar to Steindachner’s Centromochlus perugiae from 1882 (which originates from eastern Ecuador), but had a different pattern of spots.

We have occasionally been able to import Tatia from Colombia, which are probably T. altae. Apart from the shape of the spots, the very pretty yellowish base color of the Colombian animals is striking, especially in the head area. All other characteristics and properties correspond to T. perugiae. The differences in coloration between the two species (if they are species and not just location variants) can be most easily seen in the collage attached to this post. Tatia altae has a light net pattern of fine lines on a dark background, while T. perugiae has round dark spots scattered on a light background.

All driftwood catfish—including Tatia perugiae and T. altae—practice internal fertilization. The specially shaped anal fin serves this purpose. A fertilized female can therefore lay viable eggs later in the absence of males, which they prefer to do in round caves. It has been shown that these small Tatia species like it warm, with 26-28°C being the most favorable temperature.

For our customers: Tatia perugiae has code 295811 (bred) and (depending on size) 295820-295822 (wild) on our stock list. Tatia altae has code 295401 on our stock list. Please note that we only supply wholesale.

Literature:

Calegari, B. B., R. P. Vari & R. E. Reis (2019): Phylogenetic systematics of the driftwood catfishes (Siluriformes: Auchenipteridae): a combined morphological and molecular analysis. Zoological Journal of the Linnean Society v. 187 (3): 661-773

Sarmento-Soares, L. M. & R. F. Martins-Pinheiro (2020): A reappraisal of phylogenetic relationships among auchenipterid catfishes of the subfamily Centromochlinae and diagnosis of its genera (Teleostei: Siluriformes). Proceedings of the Academy of Natural Sciences of Philadelphia, 167 (1): 85-146) 

Text & photos: Frank Schäfer

Hypoptopoma psilogaster

29. August 2025

The genus Hypoptopoma comprises small to medium-sized (the largest species is just over 10 cm long) armored catfish, which at first glance look like an enlarged version of Otocinclus. A characteristic feature of this genus is that the eyes are located on the sides of the head, giving a Hypoptopoma sitting on a plant stem an almost 360° field of vision. This feature is also found in the genus Oxyropsis, which, however, has a compressed, flattened caudal peduncle, while the caudal peduncle of all members of the genus Hypoptopoma is highly oval in cross-section. Furthermore, members of the genus Nannoptopoma have a similar eye position. With a maximum length of 3-4 cm, they remain significantly smaller than Hypoptopoma.

Unfortunately, species identification is a tricky business, even though a comprehensive revision of the genus was published in 2010. Once again, we received a beautiful Hypoptopoma species from Peru. The tail fin pattern is very striking, which led to its identification as Hypoptopoma psilogaster. In addition, the distribution area specified for H. psilogaster in the aforementioned revision fits: the Ampiyacu, Itaya, Nanay, Napo, and Yaguas rivers in the western Amazon basin. It is possible that we may also receive a mix of very similar species; we can never completely rule this out.

The maximum final size of H. psilogaster is given as 7 cm standard length, i.e. without the tail fin. The animals are peaceful both among themselves and towards fish of other species. Water temperatures can range from 22 to 28°C, with average values being most favorable. The hardness and pH value are hardly significant for care; any tap water suitable for drinking is also suitable for keeping these fish. In addition to algae and other growths, you should always offer these fish some vegetables (potatoes, zucchini, carrots, etc.) as food. It will be difficult to feed them solely on the algae growth in the aquarium. These catfish also like to snack on any standard ornamental fish food, with food tablets being particularly popular.

In any case, they are pretty animals and a different kind of algae eater than usual!

For our customers: the animals have code 262262 on our stock list. Please note that we only supply wholesale.

Text & photos: Frank Schäfer

Poecilia reticulata Guppy Tricolor Cobra

22. August 2025

The meaning and nonsense of commercial names for guppys is a matter of debate. But there is no doubt that the so-called Guppy Tricolor Cobra is a truly colorful guppy. To some, the term “colorful guppy” may seem like a pleonasm, like “white gray horse” or “cold ice.” Of course, guppys are almost always very colorful. But that refers to the overall impression of the fish. 

With the Guppy Tricolor Cobra, the uneven coloring is the actual breeding goal. Each of the males looks as if an experimental child had tried out the new paint box; hardly any two specimens are completely alike. Particularly attractive are the diverse body colors. Colorful body colors are not that common in guppys, or even desirable. Many breeds are deliberately bred with black bodies, for example, in order to bring out the luminosity of the tail fin.

For our customers: Guppy Tricolor Cobra has code 418404 on our stock list. Please note that we only supply wholesale.

Text & photos: Frank Schäfer

Andinoacara pulcher (formerly: Aequidens pulcher)

22. August 2025

There are relatively few aquarium fish for which a really common popular name has developed. Andinoacara pulcher (formerly: Aequidens pulcher) is one of them. It is regularly found in aquarium books under the name “Blue Acara”. The year of first introduction is given as 1906.

As with most well-known aquarium fish, it is no longer as easy to identify a species as it was almost 120 years ago. Trips to the areas of occurrence (in this case: Trinidad and Venezuela) have brought new insights. Many very similar, but in direct comparison certainly different forms were discovered. And so we cannot be one hundred percent sure that the Blue Acaras that we have been able to offer in their natural form again for a long time (nowadays the “Neon Blue” breeding form is usually kept, see https://www.aquariumglaser.de/en/fisharchive/andinoacara-pulcher-neon-blue-2/) are really Andinoacara pulcher or perhaps belong to another closely related species. These are German offspring, the origin of the ancestors, which were probably imported decades ago, can no longer be reconstructed.

Regardless, if you are looking for beautifully colored, rather big cichlids that neither reshape the entire aquarium to their taste nor regard every aquarium inhabitant as fair game for personal amusement, Blue Acaras are a good choice. The animals reach sexual maturity at 6-8 cm in length. The sexes are hardly distinguishable externally, which is why it is best to buy a group of 6-10 animals and give away any surplus once a pair has been found. The maximum length given in the literature is up to 18 cm. Of course, nobody knows how much aquarist’s fiction is hidden here. But you should reckon with 15 cm.

Andinoacara pulcher is an open brooder with a biparental family, i.e. both partners take care of spawn and fry. If possible, they prefer a transportable breeding substrate (e.g. a rough dead leaf or similar) to another solid substrate for spawning, but they are flexible. Any drinking water is suitable for maintenance and breeding. The water temperature for this fish can be in the range 22-28°C, it will also tolerate slightly higher or lower temperatures from time to time, but this should not become a permanent condition. They will eat any standard ornamental fish food of a suitable size.

For our customers: the animals have code 609501 on our stock list. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

Nomorhamphus celebensis and N. towoetii

22. August 2025

Most species of Nomorhamphus halfbeaks come from the island of Sulawesi (formerly: Celebes). Some, such as N. ebrardtii or N. rex, are mainly traded as wild-caught specimens, others, including N. liemi, are also bred. Black Celebes halfbeaks are very rare in the trade. We can sometimes offer captive-bred specimens of Nomorhamphus celebensis of 4-6 cm in length, sometimes also wild-caught specimens. Then it gets tricky, as we do not know the exact localities and without them an exact species classification is hardly possible. There are three scientifically described species of black Celebes halfbeaks: the aforementioned N. celebensis, plus N. towoetii and N. aenigma. Another species known in the hobby, which is characterized by an orange zone in the dorsal fin area, is still the subject of debate. At present, most authors consider it to be a color form of N. towoetii. Basically it wouldn’t matter, but there are behavioral differences. N. celebensis is the most peaceful of all halfbeaks, whereas N. towoetii is considered to be very quarrelsome. We are not yet aware of any evaluations of N. aenigma in this respect.

Let’s start with N. celebensis: This species may not be as colorful, but it is peaceful. You can socialize them well with each other as well as with fish of other species. During courtship the males become deep black with light vertical bands. In earlier reports (before around 1980), N. liemi, which had not yet been scientifically described at the time, was referred to as N. celebensis. These care and breeding reports, in which the males are described as very territorial, therefore do not refer to the “true” N. celebensis. While the males of this viviparous species stop growing at around 6 cm in length, the females can grow considerably larger at around 10 cm. When breeding, it is crucial to save the young from the parents, as they are very cannibalistic. Pregnant females should not be transferred to the litter aquarium too late, otherwise stillbirths may occur, but not too early either, as the lively animals like free swimming space. As you can see, even breeding supposedly “simple” livebearers has its pitfalls.

Now to N. towoetii: as already mentioned, this species is considered quarrelsome. It remains smaller than N. celebensis, females reach a maximum length of 8 cm, males 5-6 cm. The most certain difference between the two species N. celebensis and N. towoetii is that in N. celebensis the females always remain gray, while the females of N. towoetii can turn almost as black as the males. Currently (July 2025) we have been able to import wild-caught specimens, which should be N. towoetii due to the coloration of the females, but they are extremely peaceful among themselves and even like to swim in schools.

The strange shape of their mouths suggests that these fish mainly eat insects that fall to the surface of the water. In the aquarium, however, they are very fond of flake food. Care is easy in this respect. Nomorhamphus can be found in cool running waters. They do not necessarily need a strong current, but clean water. Good filtration and regular water changes are therefore essential. Unfortunately, there is serious misinformation about the occurrence of these fish, particularly in the scientific literature, which can lead to serious mistakes in keeping them. According to the literature, N. celebensis is native to Lake Poso and N. towoetii to Lake Towuti. However, they do not and did not occur there, but in the cool tributaries of the highlands, sometimes also in runoffs. In Lake Poso the water temperature is usually between 27 and 28°C, the water is slightly alkaline (pH around 8) and the water is relatively soft (total hardness around 5° dH, of which 4° KH). In the streams where Nomorhamphus live, however, the temperature hardly ever rises above 22°C!

Unfortunately, Nomorhamphus celebensis is (at least on paper) a critically endangered species. The main reasons given for this are the invasive fish species that have been introduced into Lake Poso, water pollution from various sources and intensive food fishing. However, this assessment is put into perspective when one considers that there are at most stray Nomorhamphus in the lake itself. There is no evidence of negative consequences of catching and exporting as aquarium fish; it is very unlikely that they exist. Nevertheless, it would be nice if a stable ex-situ population of these halfbeaks could be established; we have had to learn from bitter experience in the past how quickly a commercially unimportant fish species such as N. celebensis and N. towoetii can become extinct due to economic interests that are seen as overriding.

For our customers: the animals have code 438802 (as N. celebensis) on our stocklist. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

Papyrocranus afer

22. August 2025

The knifefish are very widespread in tropical Africa with three species. With a total length of about 60 cm, Papyrocranus afer belongs to the large knifefish, while a second African species, Xenomystus nigri, which also occurs in Nigeria, is one of the smallest (Old World) knifefish with a final length of 15-20 cm. The third, generally accepted species is Papyrocranus congoensis from the Congo, which is almost never available for the aquarium; it probably grows only slightly larger than 20 cm.

Strangely enough, there are hardly any aquaristic reports on P. afer, although at least some colour forms of P. afer have very attractively pattern. However, there is a breeding report by Ong Kay Yong, which appeared in the journal TFH in 1965. According to this report, P. afer is a paternal brood carer.

Among each other the animals are said to be very pugnacious. We cannot observe an increased incompatibility in P. afer, in our fishhouse 15 – 20 cm long P. afer live peacefully together in larger numbers (about 50 specimens). But in the long term we have not yet cared for the species, therefore one should take the warnings seriously and observe the fish well if one cares for several specimens, in order to be able to intervene quickly in case of possible disputes. 

Basically Papyrocranus are twilight and nocturnal predatory fish, which are to be cared for similar to their aquaristically better known Asian relatives of the genus Chitala. Although P. afer has several geographically assignable colour forms, they have not been described as independent species or subspecies so far. The animals we usually import from Nigeria are mostly light spotted forms.

Papyrocranus are obligatory air-breathers, which regularly swim to the surface of the water to catch their breath.

For our customers: the animals have code 155305 on our stocklist. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

Protocheirodon pi

22. August 2025

In 1977 the „bible for all characin friends“ was punblished: Jaques Géry´s „Characoids of the world“. Almost at the end of this book a picture of a so far undescribed glass tetra was published that had an extremely unusual air bladder. This animal was described only one year later – in 1979 – by Richard P. Vari  as a new species, Leptagoiniates pi. The specific name refers to the shape of the air bladder that reminds one in the ancient Greek letter pi (π). Due to the transpareny of the animals the air baldder can be seen very good in live specimens. It was not easy for Vari to place the new species in a already described genus, but finally he decided to place it in Leptagoniates due to anatomical reasons.

New techniques bring new ideas. Two independent molecular analysis showed that the two species placed so far in Leptagoniates (namely L. steindachneri and L. pi) are not closely related at all, but have to be placed even in different subfamilies: L. steindachneri in the Aphyocharacinae, L. pi in the Cheirodontinae. L. pi is a species that is very close to the basal evolutionary branch of the Cheirodontinae. So recently Vari, Bruno F. Melo, and Claudio Oliviera erected a new genus for L. pi, Protocheirodon. This genus is so far monotypical; this means it contains only one known species, Protocheirodon pi. The description of Leptagoniates pi was one of the very first publications of R. Vari. Sadly this publication was one of the last of Richard P. Vari and published posthumous. He died, aged 66, on January 15th, 2016 from cancer.

To the best of our knowledge Lepatagoniates steindachneri has not been imported yet as an ornamental fish. Protocheirodon pi, on the other hand, is available from time to time from Peru. The species has a very wide distribution in South America and can be found in almost all major river systems in the central and western part of Amazonia, including the Solimoes, the Purus, Madeira, and Ucayali. The fish is found unsually over sandy bottoms in quiet waters along the banks of the rivers and in backwaters. There is no sexual dimorphism described, but we feel that the females become bigger than the males. However, this is not proofed by anatomical examination.

Keeping Protocheirodon pi is not complicated at all. We suggest the common name „Crystal Tetra“ for the species. The company of other fish makes P. pi feel safe. This must not necessarily be conspecifics, other peaceful fish can also do that job. P. pi is not a schooling fish in the strict sense of the term. Once the fish have settled in a tank they will inhabit very small territories that will be defended in a harmless way against other Crystal Tetras. One can term P. pi as an absolutely peaceful species. The fish will readily take any usual fishfood that fits in size. Plants are ignored. P. pi attains a maximum lengst of about 5 cm.

For our customers: the fish have code 266003 on our stocklist. Please note that we exclusively supply the wholesale trade.

Text & Photos: Frank Schäfer

Hoplisoma concolor

15. August 2025

Hoplisoma concolor (formerly Corydoras concolor) is a distinctive species from the Orinoco basin in Colombia and Venezuela. Its synonymization with Corydoras esperanzae was long overlooked, but is now completely undisputed. The first person to describe it, Castro, simply overlooked H. concolor in his 1987 work on the armored catfish of Colombia (the species had already been described by Weitzman in 1961), and the illustrations of C. esperanzae in this study clearly show H. concolor.

Typical for this species is the extremely steep forehead. The species name “concolor” ( = the monochromatic) essentially means that the species lacks a conspicuous melanophore pattern. However, there is an eye band (sometimes difficult to see, depending on the mood). Small juveniles have a fine dot pattern and can sometimes be confused with H. polystictus, which, however, does not have an eye band. H. polystictus is almost certainly very closely related to H. concolor, but originates from southern South America (Rio Paraguay basin). Adult animals cannot be confused.

The breeding of H. concolor is not diffucult ank possible – apart from major water changes – without any special triggers, similar to H. axelrodi. It is not often practiced because, although adult H. concolor are very beautiful. But young animals are very drab coloured and can therefore only be sold to connoisseurs.

For our customers: the animals have code 226004 on our stock list. Please note that we only supply wholesale customers.

Literature:

Castro, D. M. (1987): The fresh-water fishes of the genus Corydoras from Colombia, including two new species (Pisces, Siluriformes, Callichthyidae). Boletin Ecotrópica. No. 16: 23-57, Pls. 1-11

Text & photos. Frank Schäfer

Jordanella floridae

15. August 2025

This killifish from North America is one of the evergreens in the aquarium hobby and has delighted many generations of aquarists. Unfortunately it has become quiet around this attractive animal in the last years. But now beautiful American Flag fish are available again from Southeast Asian breeders. 

Jordanella floridae grows 4-6 cm long and is very temperature tolerant, which is why it is also well suited for stocking mini ponds in the warm season, where it reliably prevents the occurrence of mosquito larvae. Furthermore, filamentous algae are part of the food spectrum, which certainly does not annoy the pond owner. The eggs are also laid in algae cushions, the male defends the spawning ground against possible predators. In very small aquariums or miniature ponds, the American Flag is kept in pairs, otherwise group keeping is also possible without any problems.

Males and females are easily distinguished by the black spot in the dorsal fin, which only the females show.

As soon as the water temperature falls permanently below 15°C, you have to bring the American Flag into the house.

For our customers: the animals have code 327503 on our stocklist. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

Betta splendens Crowntail Black Orchid

15. August 2025

Crowntail bettas enjoy great popularity. Although the breeding form was probably already known in the 1960s and the gene for the crowntail factor is dominantly inherited, the fish only made their breakthrough in Central Europe and America at the beginning of this millennium. Their exact history is not documented, the first known verifiable mention was in Jörg Vierke’s labyrinth fish book from 1978, but crowntails had already existed for a long time by then. Freaks differentiate crowntails according to the number of splits in the free fin ray ends and several other criteria. But these are cases for specialists, such fine distinctions are not practicable in the trade.

We occasionally have wonderful black crowntails in stock under the name “Black Orchid” from a Thai breeding company. Black fighting fish have always been a special feature, as the color is inherited in a double recessive manner (i.e. “concealed”) and breeding them requires a lot of skill and breeding knowledge. The “Black Orchid” also has glossy cover colors, which makes it even more attractive.

The black crowntails should be kept in the same way as all other Siamese fighting fish, so under normal circumstances only one male should be kept per aquarium and care must be taken when socializing that the other fish do not pick at the fins. Overly lively fish species are not suitable as companions for bettas, as are veil guppies, which are very often attacked by bettas.

For our customers: the animals have code 390163 on our stock list. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

Girardinus metallicus “Black Belly”

15. August 2025

The Metallic Topminnow, Girardinus metallicus, like all Girardinus species (currently 7 species are recognized), originates from Cuba. It is the only species that has been able to establish itself in the hobby. Black-bellied males do not occur in nature, at least nobody has ever found any there; in the hobby, on the other hand, one finds almost only these beautiful animals. 

While it is generally assumed that the black-bellied (only the males have this characteristic) Girardinus metallicus is a breeding form, there are also voices to the contrary, which indicate that the courtship behavior of the black-bellied is clearly different from the courtship behavior of the normally colored animals and that it is therefore perhaps an undescribed species.

Be that as it may: the Metallic Topminnow, which is usually 3-4 cm (max. 5 cm) long in the male sex and 5 cm (max. 9 cm) long in the female, is a very lively and beautiful livebearer, whose care can be recommended without reservation.

For our customers: the animals have code 416704 on our stocklist. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

Nannoptopoma sp. Zebra Rio Tigre (LDA110)

8. August 2025

Armored catfish are known to be a very species-rich and diverse group of fish. The largest species can grow to a length of one meter; Nannoptopoma are among the smallest known species, reaching only about 3-4 cm in total length.

The genus Nannoptopoma is easily recognizable by its eyes, which are positioned very far to the sides of the head, allowing the fish to see both upwards and downwards. This eye position is otherwise only found in the considerably larger Hypoptopoma and Oxyropsis. At times, Nannoptopoma was even considered synonymous with Hypoptopoma, but the latest scientific research has reconfirmed the separation and independence of Nannoptopoma (Delapieve et al, 2018).

So far, only two species of dwarf sucker catfish of the genus Nannoptopoma have been scientifically described, namely N. spectabile and N. sternoptychum; in the hobby, we also know of two undescribed species from Peru, which were presented in Aqualog Bookazine #9 as LDA109 and 110. While N. spectabile and N. sternoptychum are not very striking in color and differ mainly anatomically (the pectoral fins are considerably longer in N. sternoptychum, and the species also has a row of conspicuous bone plates in the pectoral girdle area), LDA 109 and 110 are very attractively colored with high contrast and differ significantly from each other in color.

Freshly imported Nannoptopoma are quite sensitive, which is probably due to the quality of the holding conditions in their country of origin. Once they have successfully acclimatized (sturdy yogurt has proven to be a very effective food for rebuilding disturbed intestinal flora, Mike Meuschke, verbal communication), they are by no means extremely demanding. Sufficient dead leaves should always be available in the aquarium as a staple food (beech, oak, sea almond, small amounts of walnut). Some keepers recommend larger aquariums, which largely feed the animals on their own and offer more stable water conditions. In any case, Nannoptopoma species are only suitable for experienced aquarists, especially since they are often quite shy.

Nannoptopoma sp. Zebra / LDA110 from Peru (Rio Tigre basin) is anatomically closer to N. spectabile than N. sternoptychum and is also often referred to as N. spectabile in the trade. As with N. spectabile, the tips of the pectoral fins do not reach the base of the anal fin and there are no bony plates on the ventral side above the shoulder girdle. However, there is no doubt that LDA110 is a scientifically new, undescribed species, as N. spectabile is more or less uniformly brown in color. Nannoptopoma sp. Zebra Rio Tigre (LDA110) was and is also referred to as N. sp. “Peru,” which is unfortunate, as three of the four species mentioned here occur in Peru.

To our knowledge, breeding has not yet been reported, but the closely related N. spectabile has already been successfully bred in aquariums (Weidner & Dotzer, 2004). The reproductive behavior is reminiscent of Hypoptopoma, i.e., the animals are not cave spawners, but the eggs are laid openly (e.g., on one of the aquarium panes), but the males care for the brood until the young swim freely. Males and females seem to differ in LDA110 by the spines on their pelvic fins (with spines in the presumed males). In addition, the head coloration of some animals is rather reddish (presumed males), while others are rather pale (presumed females).

For our customers: the animals have code 271294 on our stock list. Please note that we only supply wholesale.

Literature:

Delapieve, M. L. S., P. Lehmann A and R. E. Reis (2018): An appraisal of the phylogenetic relationships of Hypoptopomatini cascudinhos with description of two new genera and three new species (Siluriformes: Loricariidae). Neotropical Ichthyology v. 15 (no. 4) e170079 (für den 18 Dez. 2017): 1-37

Weidner,T. & Dotzer,P.(2004): Klein, aber oho! Nannoptopoma cf. spectabilis. (Das Aquarium, 415,1:21-24): 2004/01:21-24

Text & photos: Frank Schäfer

Nomorhamphus cf. kolonodalensis

8. August 2025

For the first time we succeeded in importing a highly interesting, apparently small half-beak species from Sulawesi (formerly Celebes), which is most probably N. kolonodalensis. This species was scientifically described in 2000. It is named after the Kolonodale region. The Black Sulawesi Halfbeaks Nomorhamphus celebensis and N. towoetii, which were imported together with this species, also come from this region. 

As far as we know, only images of live females of N. kolonodalensis have been published so far. These correspond very well with our animals. The males are polychromatic; some match well with the color description in the original scientific description, others do not. As some doubts therefore remain, we have decided to insert a “cf.” between the genus and species names to make it clear that we do not consider the identification to be entirely certain.

Our specimens are 4-5 cm long in both sexes (total length with caudal fin). The largest specimen mentioned in the first description was 67.9 mm long (without caudal fin). Presumably the fish will still grow a little. But they are already highly sexually active. Particularly striking is the frequent beak-opening displayed by the males as an act of display and courtship. It is therefore displayed against both males and females. We were unable to establish any correlation between coloration and beak-tearing activity. A male with completely colorless fins was just as active as one with orange fins. Only the particularly striking males with red-orange fins and strong black markings in the dorsal and anal fins showed restraint.

Because of this strongly pronounced imposing behavior, the small fish should be kept in large aquaria with plenty of current and cover in the surface area (tall plants such as Vallisneria, whose leaves float on the surface of the water). Suppressed specimens could otherwise be harmed by distress. However, we have not observed any physical injuries caused by bites. Nomorhamphus species require cool water between 18 and 23°C. Apart from that, care is not difficult. The water should be slightly alkaline. Flake food is readily accepted, but feeding fruit flies (Drosophila) and live midge larvae will certainly have a positive effect on their well-being and the number of offspring. All Nomorhamphus species are viviparous.

For our customers: the namils have code 438873 on our stocklist. Please note that we exclusively supply the wholesale trade.

Text & photos: Frank Schäfer

Trichopsis schalleri

8. August 2025

Schaller’s Croaking Gourami is one of the unfortunately rarely available labyrinth fish. These pretty animals mostly come from central Thailand (they can be found comparatively far north and also in Vietnam) and grow to around 4 cm in length. This makes them slightly larger than the Dwarf Croaking Gurami (Trichopsis pumila 2.5-3 cm) and slightly smaller than the Large Croaking Gurami (T. vittata up to 6 cm).

They are very undemanding fish that are ideal for a community aquarium with small, peaceful fish from Southeast Asia – e.g. Rasbora species. In contrast to many other labyrinth fish, the males like to build their foam nest under a broad plant leaf or in caves, only rarely is it placed on the surface of the water.

Croaking gourami are so called because they can produce audible growling sounds. These sounds are produced by the fish running a bone over tendons that run over the air-filled swim bladder. Croaking gouramis play the guitar, so to speak. The croaking itself is a show of strength. The fish croak and whoever croaks the loudest wins. When mating, the males also croak to show that they are really great and strong. But the females also croak in this species and are very emancipated.

The sexes are difficult to distinguish in Trichopsis and can only be distinguished when the animals are ready to spawn. Then you can see in the backlight that the ovaries of the females rise diagonally backwards towards the middle of the body, so the intestines appear like a triangle. The testicles of the males are thin strands along the spine and are barely visible. This makes the intestines appear rounded towards the tail when viewed against the light.

Sometimes, but only very rarely find vertically striped animals can be found among our Schallers Growling Gurami. This phenomenon occurs in both sexes. It is not yet clear whether this is a mutation or another species.

The water values do not play a role in their care, any drinking water is suitable. The water temperature can be in the range of 24-28°C, or slightly higher for breeding. They will eat any ornamental fish food of a suitable size. Plants are not bothered by Croaking gouramis.

For our customers: the animals have code 470903 on our stock list. Please note that we only supply the wholesale trade.

Text & Photos: Frank Schäfer

Synodontis petricola ( = S. lucipinnis)

8. August 2025

The squeaking catfish (Synodontis) of Lake Tanganyika became world-famous when one of their species was found to have cuckoo breeding behavior. This involves the catfish sneaking their spawn to mouthbrooding cichlids. The catfish are not only hatched by the cichlids, but the brood parasites even feed on the young cichlid stepsiblings in the mother’s mouth. Many aquarists wanted to observe this fascinating and unique behavior and so the demand for Synodontis from Lake Tanganyika increased enormously. It soon became apparent that there were several species of catfish, some of which looked very similar. The identification of these catfish made life difficult for scientists and aquarists. However, it soon became apparent that many of the lake’s Synodontis do not exhibit cuckoo behavior, but are crevice spawners, depositing their eggs in rock crevices etc. and then leaving them to fend for themselves.

Among the non-parasitic catfishes, Synodontis petricola is the most frequently imported and bred species. Similar to the Tropheus cichlids of the lake, there are many different looking Synodontis petricola (“phenotypes”). It was long disputed whether these were different species. The Synodontis petricola-like ones are distinguished from the other similar-looking sqeakers in the lake by a snow-white dorsal fin spine, which makes them easy to recognize. A relatively small phenotype of this Synodontis petricola group was scientifically described in 2006 as Synodontis lucipinnis. It and a very similar, even smaller form were called “Dwarf petricola” in the hobby.

A major new study on the Synodontis of Lake Tanganyika and its inflows and outflows was recently published (September 2024) (Englmaier et al.). With freshly collected, extensive material and a re-examination of the museum material, both morphological ( = physical) and genetic characteristics were critically examined and put to the test once again. One of the findings was that S. lucipinnis falls within the variance of S. petricola and does not exist as an independent species. The authors confirm the large number of phenotypes in S. petricola, there are also (as was to be expected) genetic differences between them, but these differences are too minor to justify the establishment of separate species. In the same paper – this should only be mentioned here in passing – the cuckoo catfish S. grandiops is equated with the cuckoo catfish S. multipunctatus, so the valid name for the cuckoo catfish is again S. multipunctatus. And S. ilebrevis is synonymized with S. polli, the latter being the valid name.

Synodontis petricola is a beautiful squeaker that is one of the smaller species in the Synodontis genus, usually measuring 8-10 cm in length (very old animals may even reach 15 cm in huge aquaria). Their attractive coloration, lively nature and interesting behaviour are the reasons for their great popularity. S. petricola is currently offered almost exclusively as a captive-bred species and is a perfect catfish for Tanganyika cichlid aquariums, but also fits well in other societies. The water should have a pH value above 7.5 and be 25°C or warmer, otherwise the fish have no special requirements. They are usually peaceful with each other and with other fish. A few exceptions prove the rule. They will eat all common ornamental fish food. These catfish live in shallow water in the wild; in the wild they are only really active at night and at dusk. During the day they seek out dimly lit hiding places, which should also be offered to them in the aquarium. After acclimatization, however, S. petricola are often out and about in the aquarium during the day, especially at feeding times.

For our customers: these catfish have code 185400 (2-3 cm) to 185406 (12-14 cm) on our stock list. Please note that we only supply the wholesale trade.

Literature:

Englmaier, G. K., R. Blažek, R. Zimmermann, V. Bartáková, M. Polačik, J. Žák, D. P. Mulokozi, C. Katongo, H. H. Büscher, L. Mabo, S. Koblmüller, A. Palandačić & M. Reichard (2024): Revised taxonomy of Synodontis catfishes (Siluriformes: Mochokidae) from the Lake Tanganyika basin reveals lower species diversity than expected. Zoological Journal of the Linnean Society v. 202 (art. zlae130): 1-38.

Text & photos: Frank Schäfer