Hoplisoma sp. CW218 belongs to a group of unusual dwarf armored catfish, which is represented by relatively few species. Scientifically, only one species has been described that is very similar to H. sp. CW218, namely H. osteocarus (Colombia, Venezuela, Suriname, Orinoco basin, and coastal rivers); sometimes the species name is also written as osteocarum, but we will not discuss that here. Common characteristics are a very short head with a round snout, a clearly pronounced eye band, a steeply rising front back, a vertical smoky gray to black zone at the beginning of the dorsal fin, otherwise colorless fins, and an irregular pepper-and-salt pattern distributed over the body.
Species that can be confused with CW218 include H. osteocarus, CW104 (Colombia, Rio Cuduyari, a tributary of the Rio Vaupes), and CW142 (Brazil, Rio Purus); we hope we have not overlooked any C or CW numbers. CW218 is said to have been collected from the upper reaches of the Rio Vaupes near the town of Calamar. The similarity to CW104 is very great; the two are probably the same zoological species. Pictures of CW104 show a slightly slimmer fish, but this may be age-dependent. CW104 and CW218 differ in color from the geographically relevant H. osteocarus: a dark arc spot at the base of the caudal fin is very characteristic of H. osteocarus.
The H. sp. CW218 that we have just been able to import are 2-3 cm long and appear to be sexually mature (the females are slightly larger). The fish are unlikely to grow much longer than 4 cm. They are doing very well, but sometimes show signs of discomfort immediately after being transferred; therefore, it is advisable to be cautious when the animals come from water that differs greatly from the water in your aquarium.
For our customers: Hoplisoma sp. CW218 has code 226643 on our stock list. Please note that we only supply wholesale customers.
Text & photos: Frank Schäfer
