MITOCHONDRIAL-DNA VARIATION IN CRYPTOBRANCHUS-ALLEGANIENSIS, A SALAMANDER WITH EXTREMELY LOW ALLOZYME DIVERSITY

The distribution of mtDNA variation was measured in the hellbender, Cr yptobranchus alleganiensis, a salamander species with extremely low al lozyme variation. Fifty-seven restriction sites were mapped for the 22 6 individuals sampled. Thirty-three of these sites were polymorphic an d together determined 15 different mtDNA haplotypes. Within-population mitochondrial variation is somewhat lower in hellbenders than for oth er vertebrates. Between-population variation for hellbenders is extrem ely high; F(st) for the entire species is 0.865. A past bottleneck fol lowed by rapid mtDNA evolution and slow allozyme evolution is probably responsible for the different levels of variation in mtDNA and allozy mes in this species.