Volga and Samara Rivers, Russia.
Forms a superspecies with C. purpureus. Geographical variation weak and, except for race roseatus, not well defined; races not always separable when in worn plumage. Previously published phylogeographical analysis of mitochondrial DNA sequences, however, suggested existence of three recently diverged groups, corresponding to, respectively, Caucasus, CW Eurasia and NE Eurasia; recent re-evaluation of mtDNA data using coalescence methods, and addition of sequence data from a sex-linked gene, supported distinctiveness of Caucasian group but not the two other groups; overall, coalescence methods indicated lack of gene ﬂow among the three groups and population expansion in CW Eurasian and NE Eurasian groups, the three groups corresponding to described races, further supporting their validity#R. Five subspecies recognized.
Food and feeding
Status and conservation
Only subscribers are able to see the bibliography. Login or Subscribe to get access to a lot of extra features!