Genetic variability among endangered Chinese giant salamanders, Andrias davidianus

The endangered Chinese giant salamander (Andrias davidianus) is endemic to mainland China. Genetic divergence among six populations of the species was investigated by means of isozyme electrophoresis and mitochondrial DNA (mt DNA) sequences. Forty allozyme loci were resolved for all populations; the amount of genetic divergence among populations was comparable to that in ot her amphibians. mtDNA sequences showed a similar level of divergence. The p opulation from Huangshan is distinct from other populations, indicating the existence of localized divergence. Both allozyme and mtDNA data failed to associate the populations into a pattern corresponding to the three Chinese river systems, which may be the consequence of human relocation. Conservat ion policies should emphasize the protection of localized populations and c essation of human-facilitated introductions. Future studies should focus on investigating the divergence among localized populations from isolated mou ntain regions, particularly using more fine-grained techniques such as micr osatellite DNA.