LAUSR

Invertebrates can often persist in habitat patches too small to support larger, more mobile taxa, and as such, they may be strong predictors of conservation priorities for vertebrates. In the southeastern United States, the southern Appalachian Mountains are a well-known center of endemism for amphibians, and recent work has also uncovered extensive cryptic diversity in dispersal-limited forest invertebrate species. Here, intensive geographic and genetic sampling of a widely distributed centipede, Scolopocryptops sexspinosus [84 individuals from 42 sites across seven states, assayed for DNA sequence variation at a mitochondrial (632-bp) and nuclear (879-bp) locus] revealed two deeply divergent well-supported major clades (lineages A and B). Notably, the spatial distribution of each genetic lineage was largely geographically cohesive and broadly parapatric but with large areas of allopatry, and levels of mitochondrial divergence between lineages are comparable to that seen between named species within the genus. Indeed, no nuclear alleles are shared despite opportunities for interbreeding at locations where these lineages occur in close proximity. This study provides a foundation for follow-up work focusing on the description of species within the S. sexspinosus complex, and importantly, contributes to a growing body of research that identifies a high incidence of cryptic diversity in the southern Appalachian Mountains.