A review of the glyptosternine catfish genus Pareuchiloglanis from the upper Mekong River has seen the description of two new species.
Xu Li, Wei Zhou, Alfred Thomson, Qing Zhang and Ying Yang studied all of the Pareuchiloglanis catfishes found in the Lancanjiang, or upper Mekong, in Yunnan, and recognised five species, two of which are new to science.
Their paper, which was published in the latest issue of the systematics journal Zootaxa, says that Pareuchiloglanis gracilicaudata, P. kamengensis and P. myzostoma are valid, and names two new species as P. abbreviatus and P. prolixodorsalis.
The new Pareuchiloglanis can be distinguished from P. feae, P. polilanei, P. sichuanensis and P. tiaquanensis by their shorter adipose fin base, and by the adipose fin being separate from the caudal, rather than joined.
They can be told apart from P. sinensis, P. macrotrema, P. rhabdurus and P. longicauda by their more restricted gill opening, and from P. songmaensis by a different number of anal fin rays.
The authors wrote: "Pareuchiloglanis abbreviatus is distinguished from congeners by the tip of the dorsal fin reaching the origin of the adipose fin when depressed. Pareuchiloglanis prolixdorsalis is distinguished from P. gongshanensis, P. macropterus and P. kamengensis by lacking a sulcus between the lower lip and the base of the maxillary barbel, and differs from P. anteanalis by the shorter pectoral fin, the pectoral fin not reaching to the origin of pelvic fin.
"It differs from P. gracilicaudata, P. myzostoma, P. nebulifer and P. robusta by a caudal-fin ray count of 6+7 (vs. 7+8), and differs from P. abbreviatus by the tip of dorsal fin not reaching to the origin of the adipose fin when depressed (vs. reaching). It differs from P. songdaensis by the distance between the origin of the pelvic fin to the base of the anal fin being longer than that to the mouth (vs. equal)."
The Pareuchiloglanis genus was erected by Pellegrin in 1936 and belongs to the sisorid subfamily Glyptosterninae.
Unlike some other members of the subfamily, Pareuchiloglanis lacks adhesive apparatus on the thorax, instead having plaited adhesive organs on their paired fins.
For more information see the paper: Xu Li, Wei Zhou, Alfred Thomson, Qing Zhang and Ying Yang (2007) - A review of the genus Pareuchiloglanis (Sisoridae) from the Lancangjiang (upper Mekong River) with descriptions of two new species from Yunnan, China. Zootaxa 1440: 1-19.