A freshwater labeo-like fish has been placed in a new genus after scientists found it was unrelated to existing species.
The labeonine cyprinid, or freshwater shark, Epalzeorhynchos bicornis, has been placed in a new genus called Akrokolioplax by Zhang and Kottelat in a paper in the latest issue of the systematics journal Zootaxa.
Zhang and Kottelat said that the fish had been placed in Epalzeorhynchos in the past because it has two distinctive rostral lateral lobes on its snout.
However, closer investigation revealed that the lobes on bicornis and those of other Epalzeorhynchos had different origins and structures, so they've decided to place bicornis in a new genus of its own as it's now believed to be unrelated to Epalzeorhynchos.
Zhang and Kottelat have undertaken an in-depth redescription of the species which has included a fresh look at new specimens of the species, and a comparison with other Epalzeorhynchos species.
The species, which was described by Wu in 1977, is found in the middle reaches of the "Nu Jiang" or Salween River in China, Myanmar and Thailand and has occassionally been imported into the aquarium trade in the UK.
You can view the distribution of this species using Practical Fishkeeping's Fish Mapper application.
The cyprinid subfamily Labeoninae currently contains 27 genera which include a range of popular aquarium fish, such as the Red tail black shark, Epalzeorhynchos bicolor and the Flying fox, Epalzeorhynchos kalopterus.
For more details see the paper: Zhang, E and M Kottelat (2006) - Akrokolioplax, a new genus of Southeast Asian labeonine fishes (Teleostei: Cyprinidae). Zootaxa, 1225: 21-30 (2006).