Species limits in Pteruthius (Aves: Corvida) shrike-babblers: a comparison between the Biological and Phylogenetic Species Concepts Author Rheindt, Frank E. Author Eaton, James A. text Zootaxa 2009 2301 29 54 journal article 10.5281/zenodo.191721 ad00220f-1118-42b0-9d01-d4b89d933631 1175-5326 191721 The P. rufiventer complex Reddy (2008) examined DNA and skin specimens of both previously recognized subspecies of the complex: P. rufiventer rufiventer from the eastern Himalayas to Burma , and P. r. d e l a c o u r i from northern Vietnam . She found no fixed differences in the cyt-b sequences between the two subspecies, and differences in plumage hue were unconvincingly subtle and restricted to some of the individuals only. She concluded that the proposed geographic gap between the two subspecies may be the result of a sampling artifact, because the intervening regions of Laos and Yunnan have not been properly sampled. In the absence of any fixed characters between the two taxa, she relegated P. r. delacouri into the synonymy of a monotypic P. rufiventer . Reddy’s (2008) data suggest that differences between P. r. r u f i v e n t e r and P. r. delacouri are minute and may be clinal, especially if their ranges turn out to be connected. Although the BSC allows for accommodating subtle but diagnosable plumage differences under the rank of a subspecies, subspecies rank is not accorded if variation is clinal. Therefore, Reddy’s (2008) treatment of P. rufiventer as a monotypic species is sound under both species concepts ( Table 1 ). TABLE 1. BSC and PSC treatment of the P. rufiventer complex. PSC treatment ( Reddy 2008 ) BSC treatment (present work) Pteruthius rufiventer Pteruthius rufiventer monotypic Black-headed Shrike-Babbler