The genus name “Hydrolycus” means “water wolf”. These sabre-toothed tetras are indeed impressive predatory fish and anyone who is interested in predatory fish and can provide the appropriate space – Hydrolycus species grow to between 40 and 120 cm in length – will have exciting fish to keep at home. For obvious reasons, however, such animals are usually kept in zoos and show aquariums.
There are four species of Hydrolycus, plus the similar Rhaphiodon vulpinus (https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/rhaphiodon-vulpinus-2/). We are able to import three Hydrolycus species more or less regularly (albeit only in small numbers, the number of interested parties is manageable): H. armatus (https://www.aquariumglaser.de/en/fisharchive/hydrolycus-armatus-orinoco/); H. scomberoides (https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hydrolycus-scomberoides/) and H. tatauaia (https://www.aquariumglaser.de/en/09-characoids-tetra-relationship/hydrolycus_tatauaia_en-2/). Only the fourth species, H. wallacei, has so far only been obtained in a single specimen in 2012. Why is this species so rarely exported? We do not know. It is possible that Hydrolycus wallacei has an escape behavior that differs from the other species, which ensures that it rarely enters the nets.
Apparently Hydrolycus wallacei, H. armatus and H. tatauaia occur together in Colombia, where our current import comes from, at least locally and at times, because they were sent mixed. Unfortunately, it was again only a single Hydrolycus wallacei, which, however, now shows the species-characteristic differences. Whether Hydrolycus wallacei is actually the smallest Hydrolycus species with a maximum length of 40 cm, or whether no larger specimens have yet been documented, is beyond our knowledge. At least our individual specimen can clarify this question; however, the animal currently measures only 12-15 cm, so it is still young.
For our customers: Hydrolycus wallacei has code 259345 on our stocklist. Please note that we only supply the wholesale trade.
Text & photos: Frank Schäfer
