Zoological Studies

Vol. 44 No. 1, 2005

Phylogenetic Relationships of Labeonine Cyprinids of the Disc-Bearing Group (Pisces: Teleostei)

E Zhang

Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, China

E Zhang (2005) The disc-bearing group is composed of 4 currently recognized cyprinid genera: Discocheilus, Discogobio, Garra, and Placocheilus. This group is defined as having a lower lip modified to form a mental adhesive disc whose posterior margin is not continuous with the mental region, and includes 91 widely distributed species in tropical Africa and Asia. So far, it is represented in China by 28 species (about 1/3 of the total number) of all 4 genera. A phylogenetic analysis, based on 29 morphological characters scored from first-hand observations of 23 of the Chinese species examined, revealed that the discbearing group forms a monophyletic clade in which Garra is the basal lineage, and Placocheilus constitutes a subclade with the sister pair of Discocheilus and Discogobio. In such a phylogenetic framework, the validity of each genus of the disc-bearing group was evaluated. It was confirmed that Discocheilus, Discogobio and Placocheilus represent 3 valid cyprinid genera. Evidence provided in this phylogenetic analysis, incorporated with conclusions reached in the known literature, reveals that the monophyly and validity of Garra need to be further studied using observations of more Garra species. Additional characters should also be examined, as the characters utilized in this study and in Abebe, s with Getahun's (1999) study are insufficient to resolve the monophyly of Garra.

Key words: Phylogenetic relationship, Disc-bearing group, Labeoninae, Cyprinidae, China.

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