Scientists have described a new subfamily of suckermouth catfishes and a new species from the family Loricariidae.
The Delturinae subfamily has just been described by Roberto Reis, Edson Pereira and Jonathan Armbruster in a paper in the Zoological Journal of the Linnean Society and has been erected to accommodate the loricariid genera Delturus and Hemipsilichthys.
The authors studied the Delturus and Hemipsilichthys genera and looked at phylogenetic studies undertaken by Jonathan Armbruster to assess how the fish were related to each other. The two genera both share two unique features not seen in other loricariids, so the authors decided that they deserved to be placed in a subfamily of their own.
The Delturus and Hemipsilichthys species are all robust, wide and squat-bodied fishes broadly similar in overall appearance to Ancistrus. Hemipsilichthys typically reach around 10cm/4" in length, while Delturus normally grow to about 20cm/8".
The Hemipsilichthys genus currently contains three species, H. nimius and the sister species H. gobio and papillatus.
The Delturus genus includes D. anguillicaudatus, D. parahybae and D. carinotus. A new species, Delturus brevis, is also described in the paper from the waters of the Rio Inhonha basin in the east of Brazil.
The distribution of all known delturine catfishes is believed to be limited to the south-eastern side of the Brazilian Shield. The authors say that this means that the south east of Brazil either acts as a refugium for basal loricariid taxa or might be the point at which they evolved.
For more details on the new subfamily of plecs see the paper: Reis RE, Pereira EHL and J Armruster (2006) - Delturinae, a new loricariid catfish subfamily (Teleostei: Siluriformes), with revisions of Delturus and Hemipsilichthys. Zoological Journal of the Linnean Society. Vol. 147. pp. 277-299.