Scientists from China have described two new species of sisorid catfish from the Yunnan Province.
Kong De Ping, Chen Xiao Yong and Yang Jun Xing named the two new species as Oreoglanis jingdongensis and O. immaculatus in a paper in the latest edition of the journal Environmental Biology of Fishes.
The catfishes were discovered in the Mekong and Salween River basins in Yunnan Province, China, and reach a size of around 10-11cm/4".
Oreoglanis jingdongensis is known only from the upper Mengpian River, a tributary of the Mekong River, in Jingdong County, Yunnan. It is a rheophilic species with a long slender body, and broad flattened head, which allow it to hug the bottom in fast-moving water.
The authors said that the species is a member of the siamensis group: " can be separated from all other Oreoglanis species by lower lip with distinct median notch and caudal fin lunate with lower lobe longer than upper lobe.
"Oreoglanis jingdongensis can be separated from O. siamensis by having a blunt tip to the maxillary barbel (vs. pointed), and from O. immaculatus, O. macropterus, O. setiger and O. insignis by having the caudal fin lunate with lower lobe longer than the upper (vs. emarginate with lower lobe of about the same length as upper lobe)."
Males have a lunate caudal fin with extended principle caudal fin rays.
Oreoglanis immaculatus was discovered during the examination of specimens of Oreoglanis delacouri from the upper Salween in Yunnan. The species is also a member of the siamensis group but has a slightly stockier appearance than jingdongensis.
"Oreoglanis immaculatus can be distinguished from its congeners by the following features: lower lip with a strait median notch, posterior edge with indentations; caudal fin emarginate and lower lobe about the same length as upper lobe, having no yellow patches on sides of body below adipose fin."
The Oreoglanis genus is part of the family Sisoridae, and contains around 10 species.
For more information see the paper: Two new species of the sisorid Genus Oreoglanis Smith from Yunnan, China (Teleostei: Sisoridae). Environmental Biology of Fishes, Volume 78, Number 3 / March, 2007. DOI: 10.1007/s10641-006-0040-2.