| Glyptosternoid fish belongs to Sisoridae of Siluriformes, there are 8 genera in China, including Glyptosternum, Glaridoglanis, Euchiloglanis, Pareuchiloglanis, Parachiloglanis, Oreoglanis, Pseudexostoma and Exostoma. They distribute in Brahmaputra, Irrawaddy River, Salween River, Mekong River, Jinshajiang River, Pearl River and Red River. Distribution areas include Tibet, Qinghai, Gansu, Sichuan, Yunnan, Guizhou and Guangxi. The genera and species are abundant in Yunnan Province among the above areas.So far, eight genera and twenty-three species (Subspecies) of glyptosternoid fish had been recorded in China. With the change of collective sites, there were some morphological varies occurred. Whether these morphological varies belong to changes of genus or species, and if these morphologies vary are stable characteristics for classification, which are worth studing in taxonomy. According to the specimens kept in the Museum of Zoology Southwest Forestry College (SWFC), the taxonomic status and validity of some species collected from Lancangjiang and Nujiang of Yunnan Province, and some species of genera Pareuchiloglanis and Euchiloglanis occurred in southwest area of Sichuan province were doubtable and disputed. So their taxonomic status and validity are worth to study further.Most recorded species are contained in this work. The study used and measured 536 speciemens, including 6 genera 28 species. It was considered that selecting same specimens collected from different localities and different individuals from the same population, so it can avoid deviation and ensure reliability and consistency of the experiment results. The study combined conventional measure with multivariate morphometrical measure to compare the external morphological characteristics.Two species of Euchiloglanis have been recorded. The result considered that these species of Euchiloglanis collected from Honghe and Yalongjiang drainages including two new species. The new species E. longus sp. nov from Honghe drainage was also a new distribution record of Euchiloglanis outside of Yangtze River drainage. It can be distinguished from recorded species by the combination of following characters: the upper margin of pectoral fin base as high as the upper of gill openings or just lower a little; its base obvious wider than other two Euchiloglanis species; body slender and elongate, body depth 7.2-14.3% SL (vs. 10.3-15.5%); caudal peduncle longer, caudal peduncle depth 14.1-27.0% (vs. 28.2-46.2%) caudal peduncle length. The another new species Euchiloglanis longibarbatus can be distinguished from other species by the combination of following characters: maxillary barbel elongate and pointed, exceeding the lower of gill openings; the distance of pelvic fin origin to anal fin origin shorter than to the back end of pectoral fin base. The principal factor analysis result also considered there are 4 valid species of Euchiloglanis in China. The distribution pattern of glyptosternoid fish and differentiation of genera and species were closely related with the three uplifts of Qinghai-Xizang (Tibet) Plateau. Jinshajiang occurred firstly in the east Himalayas. The stability of Yangtze Block and the activity of Ailaoshan-Red River shear zone impeled the formation of Yuanjiang drainage, which was paralleled with Lixianjiang and became the main stream, the upper Red River. The geographic formation period of the Red River drainage was earlier than formation time of Minjiang drainage and Pearl River drainage. The interspecific differentiations and speciation of...
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