Author Archives: Frank Schäfer

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

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

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

We were able to import this cute dwarf tetra from Peru for the first time in April 2003. Since then, we have succeeded in importing it from time to time. The fish was initially provisionally called “Heterocharax sp. – Orangefin Tetra” or “Hummingbird Tetra”, sometimes also referred to as “Tyttocharax sp.”. A. Zarske scientifically described the species in 2010 as Trochilocharax ornatus and also created a new genus for it. Depending on the lighting, the barely 2 cm long jewels shimmer blue or are transparent. This dwarf tetra is extremely lively and has so far proved to be easy to keep.

Males and females are very easy to distinguish, as the males have an elongated dorsal fin and colored ventral fins. The maximum length of these animals is less than 2 cm (excluding the caudal fin), males are significantly larger than females. The hummingbird tetras are adaptable with regard to close-up feeding and chemical water conditions. Any common ornamental fish food of a suitable size is readily accepted. They ignore other fish and plants.

Interestingly, these tetras have internal fertilization. It is not yet clear how they do it, but the females lay fertilized eggs on plant leaves and roots without the presence of males; of course, they must first be kept together with males. Apart from the tiny size of the young, breeding does not present any particular difficulties. You can find a free breeding report online (in German only) here: https://www.datz.de/suesswasser/243-der-kolibrisalmler-ein-zwerg-mit-innerer-befruchtung

For our customers: The fish have code 258332 on our stocklist. Please note that we only supply the wholesale trade.

Lexicon: Heterocharax: means “deviant Charax”. Charax is a different genus of characin. Trochilocharax: after the scientific word for “hummingbirds”, Trochilidae, which in turn is derived from the ancient Greek word “trochilos”, which was used by Aristotle for a small bird. Charax is another tetra genus. ornatus: Latin, means “adorned”. Tyttocharax: ancient Greek, means “tiny charax”. Charax is another genus of characin.

Text & photos: Frank Schäfer

The genus Brycon comprises around 45 species, which are distributed across large parts of South and Central America. They hardly play a role in aquaristics, but are very important as food fish. They are medium-sized to large fish. The smallest species belong to the B. pesu complex (approx. 16 cm standard length, i.e. without caudal fin), while the largest – whose impressive appearance captivates the eye in underwater photographs and shapes our perception of Brycon species in general – can reach a standard length of over 70 cm.

The species Brycon pesu was scientifically described as early as 1845. Since then, all smaller Brycon species with a black caudal fin band and/or black adipose fin from Brazil, Bolivia, Ecuador, French Guiana, Guyana, Colombia, Peru, Suriname and Venezuela have been called “Brycon pesu”. It has been firmly assumed for decades that this is not a single species, but a species complex. The actual Brycon pesu would then probably only occur in the Guyana Shield. We have now received Brycon from the complex around B. pesu from the Araguaia/Tocantins basin in Brazil for the first time. The B. cf. pesu occurring there were only recently examined in a scientific paper (Panarari-Antunes et al, 2008). It was found that the two different color types of “Brycon pesu” from this water system are actually two different, genetically clearly representable species. One species has a red stripe in the anal fin as a clear external distinguishing mark, the other does not.

Unfortunately, we received the species without red stripes (the other one would certainly be even more attractive). We named it Brycon cf. pesu1 according to the suggestion in Panarari-Antunes et al. This Brycon may not have particularly striking colors, but in our opinion it is still an enrichment for the hobby. Tetras of this medium size class, which enliven an aquarium with medium-sized cichlids and catfish, are rather rare. There is not too much to say about the care requirements of Brycon cf. pesu1. They are lively schooling fish, playful and peaceful. As this is a first import, we are not yet able to provide any long-term experience. Our animals willingly accept any common ornamental fish food, the water temperature can be between 22 and 25°C, probably a little higher is also possible. Other fish species from the Araguaia/Tocantins have shown good adaptability to different water parameters (pH and hardness). In nature, the water there is soft and slightly acidic. The aquarium for Brycon species must be well covered, as they are excellent jumpers.

For our customers: the animals have code 212713 on our stock list. Please note that we only supply the wholesale trade.

Literature:

Panarari-Antunes, R. S., Prioli, A. J., Prioli, S. M. A. P., Júlio Jr, H. F., Agostinho, C. S., & L. M. Prioli (2008): Molecular variability in Brycon cf. pesu Müller and Troschel, 1845 (Characiformes: Characidae) from the Araguaia-Tocantins basin. Genetics and Molecular Research, 7(1), 95-106.

Text & photos: Frank Schäfer

Internationally, the largest serrasalmid species are called “pacu”: the red bellied pacu (Piaractus brachypomus, formerly Colossoma brachypomus or C. bidens) from the Amazon system, its twin species P. orinoquensis, which has only been differentiated from it since 2019, the yellow pacu (P. mesopotamicus) from the Parana-Paraguay system and the black pacu or cachama (Colossoma macropomum) from the Amazon. They all grow to around 80 cm in length and weigh over 20 kg. They are kept in aquaculture as excellent food fish and one species – the red bellied pacu – is probably now widespread in the tropics worldwide. In their native countries, however, these pacus are called Pirapitinga and the silver dollars of the genus Myletes & Co are referred to as pacus.

Anyway, red pacus are a must in any display aquarium as they are impressive creatures. However, we do not import them as large fish, but as small fish just a few centimetres long. They are usually bred ones from South-East Asia. As juveniles, red bellied pacus imitate a notorious cousin, the Red Piranha (Pygocentrus nattereri). In fact, they are almost indistinguishable from each other in terms of color. It is called Batesian mimicry when a harmless species imitates a defensive species and thus benefits from the fact that potential predators tend to be cautious.

Aquaristically, of course, it is known that piranhas represent the carnivorous branch of serrasalmids, while pacus are mainly vegetarians. Large animals love to eat fruit and nuts that fall from trees into the water. As this food is very rich in nutrients, the water under such trees is often heavily polluted with putrefactive substances and very low in oxygen. Pacus can withstand this and some species even develop an auxiliary respiratory organ at certain times in the form of a greatly enlarged, very well supplied with blood lip, through which additional oxygen enters the organism when the fish swims on the water surface.

Piaractus brachypomus is relatively unspecialized. It is also found in clean waters and as an opportunist it also eats small fish, shrimps etc., so it is not a pure vegetarian.

Keeping Pacus is easy, but only recommended for people who have huge aquaria. Piaractus brachypomus get on well with each other, but small fish are regarded as food supplements.

For our customers: the animals have code 218501 (4-6 cm) on our stock list. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

Pygocentrus are the most famous and aquaristically most important piranhas. In contrast to all other piranhas, Pygocentrus are always schooling fish. They are less keen on fin pieces of other fish than Serrasalmus and Pristorycon species and with their particularly sharp teeth they can bite whole pieces out of a body. However, the Pygocentrus species are by no means bloodthirsty monsters either, but opportunists that use any food – often of plant origin – that is available.

Pygocentrus cariba is a beautiful species that is regularly found in the trade and represents the shoaling piranhas in the Orinoco. The large humeral spot (= shoulder spot) is typical of the species and is most pronounced in adolescent and young adult fish. Very small animals (under approx. 4 cm in length) do not yet show the humeral spot. Very old animals, like all Pygocentrus species, tend to be very darkly colored, in which case the species can hardly be distinguished. The species name cariba is only available via a caption (which authors before 1993 usually considered insufficient); Fink (1993) revised the genus Pygocentrus and established cariba as the correct species name for the shoal piranha with shoulder spot (principle of the “first reviser”), whereby the name P. notatus, which was previously considered valid, became a synonym.

This piranha usually grows to a maximum length of approx. 25 cm, the largest length stated in the scientific literature is 27.9 cm total length (including caudal fin).

For our customers: P. cariba has the code numbers 292600 (2-4 cm) to 292607 (18-22 cm) on our stock list. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

It’s amazing how many new, attractive tetra species have been discovered recently! Among them is Hyphessobrycon peugeotorum, which was only scientifically described in 2013 under the name H. peugeoti. It originates from the Brazilian state of Mato Grosso (middle drainage of the Rio Juruena, upper basin of the Rio Tapajós). The unusual species name does not refer to the French car builders, but (quotation): “Hyphessobrycon peugeoti is patronymic to the Peugeot family, who invented the Peugeot pepper mill mechanism in 1842 and whose manufacturing business led to the establishment of a carbon sink reforestation project in the fazenda São Nicolau, in central Brazil, and eventually to the discovery of this new species.” According to the rules of zoological naming, in this case (naming after several individuals, not after a single individual) the Latin plural genitive must be chosen for the species name – i.e. the word ending -orum – and not, as happened, the Latin singular genitive ending in -i.

Apart from that, Hyphessobrycon peugeotorum is a beautiful fish that we can offer as offspring. The species grows to a length of 4-5 cm and is completely peaceful. An experience in the photo tank indicates how the animal should be cared for in order to achieve optimum coloration. In our fishhouse, a male showed mating coloration and developed a black caudal fin (in normal coloration, the caudal fin is transparent and colorless). We caught the animal and some conspecifics, put them in the photo tank and waited. It shouldn’t normally take long for the now decolored animal to show mating colors again. Not so! Nine days passed and nothing happened. We warmed the water, added humic substances, fed live food, changed the water – everything you do to get tetras going. Nothing. Then we darkened the tank considerably! And now it worked. Apparently Hyphessobrycon peugeotorum likes it a bit dim. To each his own!

For our customers: the animals have code 261499 on our stocklist. Please note that we only supply the wholesale trade.

Text & photos. Frank Schäfer

PS: As we have learned, an objection was raised against the change of the species name peugeoti to peugeotorum, so that the species is currently more frequently referred to as H. peugeoti again.

The Rainbow Emperor Tetra (Nematobrycon lacortei) is certainly one of the most attractive tetras in South America. Its home is in western Colombia where it is caught in the catchment area of the Rio San Juan. Males and females can be easily distinguished by the color of the iris. Already in small juveniles the males have a red, the females a blue iris.

To the same genus belongs the usually better known emperor tetra Nematobrycon palmeri. Nematobrycon can only be described as schooling fish to a limited extent, since the males at least occasionally defend territories against conspecifics – and this can happen quite violently. Your aquarium should therefore contain structure-forming elements such as roots and large plants.

Emperor tetras can be kept in medium hard water, but for breeding it should be soft and acidic. They will eat almost all offered foods, for a good spawning it is recommended to feed black mosquito larvae (Culex) regularly.

For our customers: the fish have code 272504 on our stocklist. Please note that we supply exclusively to wholesalers.

Photos F. Schäfer, Text K. Diehl

With over 130 species, the genus Hyphessobrycon has become very confusing. New species are still being discovered. It has long been known that Hyphessobrycon is an artificial collective genus and that the species in it are not necessarily closely related to each other. For this reason, “groups” have been defined within Hyphessobrycon from time to time since the 1970s in order to better structure them.  One of these groups is that of the flag tetras, the so-called Hyphessobrycon heterorhabdus group. It is characterized by the fact that three different coloured longitudinal bands can be seen in life, namely one red, one black and one white. However, depending on the assessment of the respective researchers, other characteristics are also used to differentiate between groups, such as the presence or absence of spots in the shoulder area ( = humeral spots) or on the tail root.

Hyphessobrycon montagi clearly belongs to the Hyphessobrycon heterorhabdus group in terms of coloration, although the red longitudinal band is limited to a short piece on the caudal peduncle. However, this species, which was only scientifically described in 2014, has two species-specific unique features: two  humeral spots, which are arranged in a specific way, and an additional caudal root spot. In the most current, DNA-based review of all tetras (Melo et al. 2024), H. montagi is nevertheless placed in the Hyphessobrycon heterorhabdus group. According to current opinion, it includes H. amapaensis, H. cantoi, H. heterorhabdus, H. ericae, H. montagi, H. sateremawe and H. wosiackii. Externally very similar is the Hyphessobrycon agulha group with Hyphessobrycon agulha, H. clavatus, H. eschwartzae, H. herbertaxelrodi, H. klausanni, H. loretoensis, H. lucenorum, H. margitae, H. metae, H. mutabilis, H. peruvianus, H. wadai and H. zoe. However, both groups do not appear to be monophyletic, i.e. their members must be placed in different genera in the long term despite external similarities.

Some of the tetras in the two groups mentioned are aquarium veterans, others have never been kept and bred alive in the aquarium. We now have H. montagi – originally from Brazil: headwaters of the Rio Arapiuns (Rio Branco and Rio Aruã), the lower Rio Tapajós basin and small, direct tributaries of the Rio Amazonas (Igarapé da Ponte) in the state of Pará – available as German offspring for the first time. The animals differ very strikingly in their behavior from the well-known H. heterorhabdus and H. amapaensis. At least our offspring of H. montagi are much more involved in shoaling behavior. Although tetras are generally referred to as “schooling fish”, this is only true to a very limited extent. In reality, most tetra species prefer a certain degree of individuality in everyday life. They only show true shoaling behavior very rarely, namely when they feel threatened. One of the few exceptions are the rummy noses (Petitella bleheri & Co.), which actually always swim in shoals. And Hyphessobrycon montagi are very similar to these animals in their behavior.

The aquarium care of H. montagi is simple and typical of tetras. There are hardly any external differences between the sexes, the females are just slightly more robust. In the wild, females ready to spawn can be found from March to August. The animals live there in clear streams between 0.8 and 20 m wide, clear water with a moderate current, sandy bottoms with accumulations of leaves and at a relatively high water temperature of around 29°C. Adaptability to other water parameters is good, however. The only thing to watch out for is clean, low-germ water. They will eat any ornamental fish food of a suitable size.

For our customers: H. montagi has code 261373 on our stocklist. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

Literature:

Melo, B. F., R. P. Ota, R. C. Benine, F. R. Carvalho, F. C. T. Lima, G. M. T. Mattox, C. S. Souza, T. C. Faria, L. Reia, F. F. Roxo, M. Valdez-Moreno, T. J. Near & C. Oliveira (2024): Phylogenomics of Characidae, a hyper-diverse Neotropical freshwater fish lineage, with a phylogenetic classification including four families (Teleostei: Characiformes). Zoological Journal of the Linnean Society v. 202 (no. 1): zlae101: 1-37

Silver dollars are the herbivorous counterparts to the carnivorous piranhas. Among them, the genus Metynnis – recognizable by its long, flat adipose fin – is the most important aquaristically, as its members still fit reasonably well into standard aquariums with a final size of 15-20 cm. Representatives of other genera can grow considerably larger. One species in particular has been represented in the hobby for decades as the “silver dollar”, albeit almost always with an inaccurate scientific name.

In fact, this fish, which used to be referred to in the trade as M. schreitmuelleri and M. hypsauchen, is actually M. altidorsalis. Due to the sometimes very confusing nomenclature of these tetras, we will not go into further detail here. The fact is that the “silver dollar” M. altidorsalis is regularly available in the hobby in good numbers as offspring from Southeast Asia and is usually traded under the name M. hypsauchen. The small black spots on the dorsal fin are a fairly good way of recognizing this species. Juveniles are usually silver-colored on the body, but adult specimens often show a black shoulder spot and irregular dark bands on the back. Males and females differ clearly in the shape of the anal fin, which in the female is narrow and evenly straight or slightly convex at the front edge, but in the male is broadly bulging in the front area and has a broad black edge.

Just for the sake of completeness: the species Metynnis hypsauchen really exists, M. schreitmuelleri (and others) are a synonym, the species is widely distributed in the Amazon, Rio Paraguay and northern Guyana Shield systems (Bolivia, Brazil, Guyana, Colombia, Peru and Venezuela), but is rarely encountered in the hobby. The “true” M. hypsauchen can be recognized in adults by the black ventral fins (colourless in M. altidorsalis) and by the fact that in sexually mature males the front of the anal fin is divided into two lobes of unequal size (only a single lobe in M. altidorsalis). Juveniles of many Metynnis species are very similar to each other. As far as we could research, Metynnis hypsauchen has no black dots in the dorsal fin (M. altidorsalis always has).

Originally, M. altidorsalis comes from rivers of the northern and eastern Guyana Shield, i.e. Guyana, French Guiana and Surinam. However, as breeding of this tetra with a maximum length of 14 cm has been successful since the 1950s, the species is rarely imported as a wild catch.

Metynnis are schooling fish and should always be kept in larger groups (from 8 specimens upwards). They are herbivores and, in the long run, even hard plants such as Anubias fall victim to them. A Metynnis aquarium is therefore decorated with root wood, stones, bamboo etc. Even though the fish will generally eat any commercially available ornamental fish food, plant material (leaf lettuce, dandelion etc.) should be a fixed part of the diet. The chemical composition of the water is irrelevant for their care, the temperature can be between 22 and 30°C. Silver dollars are free spawners on fine root tufts etc. and do not practice broodcare.

For our customers: the animals have code 267812 (3-4 cm) and 267814 (5-7 cm, photos) on our stock list. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

The yellow Congo tetra (Alestopetersius caudalis) is a popular and frequently offered ornamental fish. The species originates from the Congo, where it is at home in the lower reaches of the African river. Wild-caught fish are very rare in the trade. The species was first imported around 1950 and was soon bred. The animals in the trade today are almost without exception captive-bred, mostly from Indonesia, but other professional breeders in Europe and Asia also have the species in their range. 

On the occasion of the presentation of a small video (https://www.youtube.com/watch?v=7uXLpgRDoME), the question was raised via the comments function as to whether the animals shown (captive-bred from Indonesia) are not Alestopetersius tumbensis rather than A. caudalis. In fact, the two species are extremely similar and they also occur together – at least in places. From a scientific point of view, the most important difference between the two is the shape of the teeth: five-pointed in caudalis, many-pointed (8-9 points) in tumbensis. The different tooth shape was considered so important that a separate genus Duboisialestes was even established for tumbensis (plus bifasciatus). In addition, preserved specimens can be distinguished by their black markings. In A. caudalis, a broad dark longitudinal band extends from the shoulder patch to the caudal fin, whereas in A. tumbensis the longitudinal band is much narrower and there is a clear gap between the shoulder patch and the longitudinal band. Unfortunately, you can’t see this at all in live specimens, or can only see a hint of it.

The question came as a surprise to us, because although the species A. tumbensis (the genus Duboisialestes was declared a synonym of Alestopetersius by Munene & Stiassny in 2012) was described in 1951 on the basis of specimens imported into the Netherlands for the ornamental fish trade, it has not been mentioned in the hobby since then as far as we know. We do not kill animals for identification purposes, but we were able to recognize the shape of the teeth from a macro photograph of the mouth of one of our fish: clearly five-pointed, i.e. A. caudalis.

The exact species identification of African small tetras is and remains a complex matter. Not only aquarists have difficulties with this, but also professional ichthyologists. The markings given in the scientific papers (especially black bands, stripes etc.) are, as already mentioned, often only vaguely recognizable or not recognizable at all in living animals. The lesson for us from this story is that we will look twice as closely the next time we import wild-caught yellow Congo tetras. Perhaps we will discover A. tumbensis among them and then be able to provide a live photo of the species (as far as we know, none exists so far). Who knows, maybe you can also see differences between the two species in live animals …

By the way: general information on Alestopetersius caudalis can be found here: https://www.aquariumglaser.de/en/fisharchive/alestopetersius-caudalis-2/

For our customers: the animals shown in this post, captive bred from Indonesia, have code 138004 (xlg) on our stocklist. Please note that we only supply the wholesale trade.

Literature:

Boulenger, G. A. (1899): Matériaux pour la faune du Congo. Zoologie.–Série I. Poissons nouveaux du Congo. Quatrième Partie. Polyptères, Clupes, Mormyres, Characins. Annales du Musee du Congo (Ser. Zoologie) v. 1 (fasc. 4): 59-96, Pls. 30-39.

Géry, J. (1995): Description of new or poorly known Alestinae (Teleostei: Characiformes: Alestidae) from Africa, with a note on the generic concept in the Alestinae. aqua, Journal of Ichthyology and Aquatic Biology v. 1 (no. 4): 37-64.

Hoedeman, J. J. (1951): Studies on African characid fishes I. The tribe Alestidi. Beaufortia v. 1 (no. 3): 1-8.

Mbimbi Mayi Munene, J. J. & M. L. J. Stiassny (2012): A new Alestopetersius (Characiformes: Alestidae) from the Kwilu River (Kasai basin) of central Africa; with a phylogeny for the genus and synonymy of Duboisialestes. Zootaxa No. 3166: 59-68.

Poll, M. (1967): Révision des Characidae nains Africans. Annales, Musée Royal de l’Afrique Centrale, Tervuren, Série in 8o, Sciences Zoologiques No. 162: 1-158

Text & photos: Frank Schäfer

The Parodontidae are a relatively small group of bottom-dwelling tetras. The family consists of three genera with a total of approx. 32 species. The genera are distinguished from each other by two characteristics: firstly, the number of unbranched rays in the pectoral fin: one each in Parodon and Apareiodon and two in Saccodon; and secondly, the lack of teeth in the lower jaw in Apareiodon and Saccodon, whereas Parodon has teeth there. Unfortunately, the dentition features are not recognizable in living animals, which is why species identification and even genus assignment is often only very vague, as all species have a fairly generalized appearance. The differentiation of species in scientific descriptions is also mainly based on the shape of the teeth. In the hobby, however, the family Parodontidae is only occasionally represented by a single species, namely Apareiodon affinis from Paraguay (see https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/apareiodon-affinis-2/), which is why they are rarely encountered.

We have now been able to import a member of the Parodontidae from Peru. As all the specimens arrived alive, it was/is not possible to identify them precisely. However, only three species of Parodontidae are known from Peru so far: Parodon buckleyi, P. pongoensis and Saccodon wagneri. So we started by looking at the descriptions of these three species, which fortunately are all illustrated. This enabled us to quickly rule out Saccodon wagneri, which was described in 1863, as in this species the dorsal fin is so far forward that its end is still before the base of the pelvic fins. In our fish, the dorsal fin sits roughly above the pelvic fins. This leaves Parodon buckleyi, described in 1887, and P. pongoensis, described in 1942. Both look very similar; however, P. pongoensis is known in scientific collections with specimens from the vicinity of Pucallpa (drainage of the Rio Ucayali), while P. buckleyi is reported much further north. As the Pucallpa region is an important area for ornamental fish collectors, it is quite likely that our specimens come from there and belong to the species Parodon pongoensis. However, we do not have any final certainty about this, which is why we refer to the species on our stock list as Parodon sp. cf. pongoensis (the “sp. cf.” means “not exactly determined, but very similar to”).

Apart from the occurrence in Peru, which is also the type locality of P. pongoensis (forest brook, foothills at Pongo de Manseriche, Marañón River drainage, Peru), this species is widespread and also occurs in the drainage of the Orinoco in Colombia, adjacent to Peru in Ecuador and further south in Brazil (state of Goiás, Formosa, river Água Quente, tributary of the Paranã, catchment area of the Tocantins). The maximum length is probably around 12 cm. In larger animals, the lower caudal fin lobe turns more and more black; this is not yet visible in our juveniles, which are currently 3-4 cm long.

We have not noticed any special features in terms of care so far. The lively animals like to swim in groups with their own kind. Other fish are hardly noticed. The water temperature can be between 22 and 26°C. The water values are unimportant as long as the water is clean. They feed on aufwuchs and can be used as “algae eaters”. However, they will also eat pretty much any common ornamental fish food that fits in their mouths. P. pongoensis is therefore a diurnal algae eater for South American aquaria, a stylish alternative to the always somewhat secretive suckermouth catfish.

For our customers: the animals have code 275882 on our stocklist. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

The regrouping of large fish families continues. After the barbs, armored catfish and cichlids, it’s now the turn of the characins. A major revision was published in September 2024, prompting us to retrain once again. Not all tetra species have been included yet, so it will certainly take a few years before the new name combinations are generally used. We are also being conservative and cautious for the time being and are waiting to see what the future brings. 

Aquarists can easily follow the reintroduction of the genus name Megalamphodus for the phantom and rosy tetras in the broadest sense. In English they are all referred to as “rosy tetras”, based on the most common species in the hobby, Megalamphodus rosaceus (formerly often referred to as Hyphessobrycon ornatus, see https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hyphessobrycon-rosaceus-ornatus-2/). Within the rosy tetras, three species are well defined, namely the bleeding hearts. There are three of them: M. erythrostigmus (https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hyphessobrycon-erythrostigma-2/), M. pyrrhonotus (https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hyphessobrycon-pyrrhonotus-2/) and M. socolofi (https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hyphessobrycon-socolofi-var-green-2/. All have a bright red shoulder spot, which has earned them the interantional name bleeding hearts.

In spring we often receive very large and fully-grown Megalamphodus erythrostigmus ( = Hyphessobrycon erythrostigma) from Peru, very magnificent fish, as is the case now. We would like to take this opportunity to point out the name changes.

For our customers: the animals have code 260107 (sh, i.e. show size) on our stocklist. Please note that we only supply the wholesale trade.

Text & photos: Frank Schäfer

The lemon tetra, Hyphessobrycon pulchripinnis, is one of the most popular aquarium fish of all and can be found in the standard range of pet shops all over the world. As with so many everyday species, little thought is given to them, but the lemon tetra holds many secrets!

Its native habitat was unknown until 1980, although the species was described as early as 1937. The first description was based on aquarium fish imports whose origin was unknown and only vaguely stated as “probably Amazonas”. Although breeding the fish is not easy (randomly matched pairs often do not spawn, the females have to be brought to spawn at regular intervals so that the spawn remains fertile, etc.), wild catches were hardly ever made and it was not until 1980 that Gery discovered that the home of the lemon tetra is in the lower Amazon basin, more precisely in the middle and lower Tapajós between Itaituba and Jacare Acanga, as well as in streams that flow into the Rio Curua do Sol. Other authors also mention the Xingu and the Tocantins.

We have recently received wild catches of H. pulchripinnis from the Rio Cuiaba in the state of Mato Grosso (Brazil). This is an extremely rare event and gave us food for thought. As you can see from the picture of our supplier, freshly caught animals are crystal red. But in the aquarium, the animals usually discolor. This phenomenon is known from many fish species. The cause is most probably our clean aquarium water. In nature, the water is almost always cloudy due to clay or other suspended particles. The coloration of a fish cannot be controlled arbitrarily. This is done by hormones whose production is triggered by stimuli perceived by the eye (light, shade, water turbidity, color of the substrate, etc.). Although this explains very well why most fish in bright, sparsely furnished aquariums with little structure are very pale in color, it does not explain why they sometimes show bright colors after a certain period of time.

A group of “Muzel Red Cherry” tetras are swimming in one of our tanks in the show aquarium at Aquarium Glaser. They are imports from Brazil, but we assume that they were bred there. The Muzel are predominantly bright red-colored animals, but there are also some with a yellow body color. These yellow animals look very similar to lemon tetras. In the yellow Muzel tetras, the shoulder spot (= humeral spot) is also strongly pronounced, which is only very faintly visible in red Muzel tetras. All fins of both Muzel colors are bright red. This clearly distinguishes them from “true” lemon tetras, which at best have faintly orange dorsal and anal fins. The caudal fin of “true” lemon tetras is always transparent and colorless. “Bolivia Orange” lemon tetras also have this characteristic (see https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hyphessonbrycon-cf-pulchripinnis-bolivia-orange/). 

Obviously there is a whole circle of forms around H. pulchripinnis, which includes the following species/forms: 1. the “classic” H. pulchripinnis, which has been at home in aquaria since 1937 (colorless caudal fin, usually also dorsal and anal fins, anal fin with yellow and black line on the leading edge, dorsal fin also with black on the leading edge); 2. the pulchripinnis “Tapajós”, as illustrated in the Aquarium Atlas Volume 1 (cuvette photo on site), which lacks the black line at the beginning of the anal and dorsal fin; to our knowledge, this species is not represented in the hobby or is not distinguished from the “normal” lemon tetra; 3. the “Bolivia Orange”, which has existed in the hobby since around 1980 (colorless caudal fin, dorsal and anal fins bright red, black line at the front edge of the anal fin missing); 3. the “Muzel Cherry Red”, in which all fins and the body are bright red, black line on the front edge of the anal fin is missing, in the hobby since about 2021; 4. the “Muzel Yellow”, which looks like the “Muzel Cherry Red”, but with a yellow-orange body. The mystery surrounding the sometimes crystal red “normal” lemon tetras remains unexplained, of which our supplier wrote to us: “In fact I see most of the tetras from Cuiaba like this (note: red is meant), I have already received some to send to China and after a few weeks most of them lose their color, or some get a better color…. it’s a shot in the dark…”

Keeping all lemon tetras is very easy and even beginners can manage it. The up to 4.5 cm in length animals are kept in groups in well-structured aquaria, where each fish soon occupies a tiny territory. They will eat any common fish food and the temperature can be between 22 and 28°C. The water should (but does not have to) be soft and slightly acidic, then the colors are at their best.

For our customers: the “normal” captive-bred lemon tetra has code 261603, the wild-caught tetra from the Mato Grosso 261642 on our stock list. Please note that we only supply the wholesale trade.

Text: Frank Schäfer, photos: H.-J. Mayland, E. Schraml, F. Schäfer

The lemon tetra, Hyphessobrycon pulchripinnis, is one of the most popular aquarium fish of all and can be found in the standard range of pet shops. As with so many everyday species, little thought is given to them, but the lemon tetra holds many secrets!

The ancestors of the animals that we can occasionally offer as beautiful captive-bred specimens are said to originate from Bolivia. They differ from the well-known lemon tetra (from Brazil) by their intense orange color and the absence of the otherwise typical black fin fringe in the anal fin. According to our breeder, the fish also differ in their spawning behavior. This orange lemon tetra is therefore presumably a new, undescribed species.

They are very easy to keep and can even be kept by beginners. The up to 4.5 cm long animals should be kept in groups in well-structured aquaria, where each fish soon occupies a tiny territory. They will eat any common fish food and the temperature can be between 22 and 28°C. The water should (but does not have to) be soft and slightly acidic, then the colors are at their best.

For our customers: the new animals, which we call “Orange Bolivia”, have code 261632, the classic lemon tetra 261603. Please note that we only supply the wholesale trade.

Text Frank Schäfer, Photos: Frank Schäfer and H. J. Mayland/Aqualog-Archives

Of course, this fish is anything but a novelty and has been imported in relatively large numbers for many years. But isn’t it beautiful? This small animal is an ideal companion for the cardinal tetra (Paracheirodon axelrodi), with which it also occurs in the wild. Poecilocharax weitzmani grows to 3-4 cm and is relatively widespread in the upper Amazon and upper Orinoco. It is found in Colombia, Venezuela, Brazil and Peru. Despite its large mouth, it is a peaceful fish. 

However, P. weitzmani is a truly special characin, as – in contrast to most other characin relatives – it is a cave breeder with brood care. In the aquarium, the males occupy hollow pieces of bamboo as breeding grounds and guard the spawn there until the young hatch. However, breeding is not easy, because in order for the spawn to develop well, you need water values similar to those in nature: hardness practically undetectable and pH around 4.5-5. You need some experience to keep such water stable over a longer period of time. It is therefore not advisable to aim for such water values for normal keeping. Just as with the cardinal tetra, the adaptability to water values as they come out of the tap in Central Europe is very good. Even in such water, the small fish reach an age that is 5-10 times longer than in the wild.

We can currently offer P. weitzmani from Colombia and Brazil. Basically, we can’t see any visual differences between the two local forms, but the Brazilian specimens are currently much larger, almost fully grown. And among them are a few (1-2 animals per 500 specimens) male individuals with a brilliant red coloration that we have not (consciously) seen before. So far, P. weitzmani has only been bred by specialists interested in behavioral studies due to its abundance and the resulting low price; breeding is not economically worthwhile. It is possible that this will change now that this magnificent variety has become known.

There are observations from aquarists that describe P. weitzmani as shy. This does not correspond with our observations. The animals photographed, for example, were imported only a few days ago and already present themselves as if they had been born there in the very sparsely furnished photo tank with a few pieces of wood and leaves. With regard to all care factors (food, temperature, lighting, furnishings), please refer to the extensive literature on cardinal tetra. P. weitzmani does not have any significantly different requirements with the exception of the aforementioned spawning caves.

For our customers: the animals have code 281004 (md-lg) and 281005 (lg-xlg) on our stocklist. Please note that we only supply the wholesale trade.

Text & Photos: Frank Schäfer