Long-term sky islands generate highly divergent lineages of a narrowly distributed stream salamander (Pachyhynobius shangchengensis) in mid-latitude mountains of East Asia.

Our results suggest that the niche conservatism of P. shangchengensis and sky island effects may have led to long-term isolation between populations. In sky island refuges, the mid-latitude Dabie Mountains have provided a long-term stable environment for P. shangchengensis, which has led to the accumulation of genetic diversity and has promoted genetic divergence.