title: Morphometric studies of genus Placocheilus (Teleostei: Cypriniformes) from Red River, China.
abstract: It is practically difficult to differentiate Placocheilus robustus and Placocheilus caudofasciatus from Red River drainage of China. Without stated reasons, P. robustus has been assumed as the synonyms of P. caudofasciatus. The present study aims to decipher the morphological differences between two species so as to provide reliable clues for their classification by multivariate morphometry. A total of 72 specimens of two species in genus Placocheilus were examined. Besides morphological character comparisons, 10 anatomic landmarks were utilized and 23 frame structures and 15 general characters measured. The scatter plot results of principal component analysis showed that all specimens were clustered together and could not be defined as two distinct species. No significant morphological differences existed in four diagnostic characters between P. robustus and P. caudofasciatus. Thus the results of the present study fail to support P. robustus as a valid and independent species.
authors.affiliation: Key Laboratory of Forest Disaster Warning & Control in Yunnan Province, Faculty of Forestry, Southwest Forestry University, Kunming Yunnan, 650224, China .weizhouyn@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Forest Disaster Warning & Control in Yunnan Province, Faculty of Forestry, Southwest Forestry University, Kunming Yunnan, 650224, China.
authors.forename: Min-Hui
authors.initials: MH
authors.lastname: Li
authors.affiliation: Key Laboratory of Forest Disaster Warning & Control in Yunnan Province, Faculty of Forestry, Southwest Forestry University, Kunming Yunnan, 650224, China.
authors.forename: Chun-Ping
authors.initials: CP
authors.lastname: Wang
authors.affiliation: Key Laboratory of Forest Disaster Warning & Control in Yunnan Province, Faculty of Forestry, Southwest Forestry University, Kunming Yunnan, 650224, China.
authors.forename: Mi
authors.initials: M
authors.lastname: Qi
mesh_terms: D000825:Animal Structures / Q000737:chemistry / Q000254:growth & development; D000818:Animals; D049628:Body Size; D002681:China; D003531:Cypriniformes / Q000145:classification / Q000254:growth & development*; D009929:Organ Size; D025341:Principal Component Analysis; D045483:Rivers
keywords: Evidence for taxonomy; Mophomemetrics; Placocheilus caudofasciatus; Placocheilus robustus; Principal component analysis