Data from: Past climate change drives current genetic structure of an endangered freshwater mussel species

Historical-to-recent climate change and anthropogenic disturbance affect
species distributions and genetic structure. The Rio Grande watershed of
the United States and Mexico encompasses ecosystems that are intensively
exploited, resulting in substantial degradation of aquatic habitats. While
significant anthropogenic disturbances in the Rio Grande are recent,
inhospitable conditions for freshwater organisms likely existed prior to
such disturbances. A combination of anthropogenic and past climate factors
may contribute to current distributions of aquatic fauna in the Rio Grande
basin. We used mitochondrial DNA and 18 microsatellite loci to infer
evolutionary history and genetic structure of an endangered freshwater
mussel, Popenaias popeii, throughout the Rio Grande drainage. We estimated
spatial connectivity and gene flow across extant populations of P. popeii
and used ecological niche models (ENMs) and approximate Bayesian
computation (ABC) to infer its evolutionary history during the
Pleistocene. structure results recovered regional and local population
clusters in the Rio Grande. ENMs predicted drastic reductions in suitable
habitat during the last glacial maximum. ABC analyses suggested that
regional population structure likely arose in this species during the
mid-to-late Pleistocene and was followed by a late Pleistocene population
bottleneck in New Mexico populations. The local population structure arose
relatively recently, perhaps due to anthropogenic factors. Popenaias
popeii, one of the few freshwater mussel species native to the Rio Grande
basin, is a case study for understanding how both geological and
anthropogenic factors shape current population genetic structure.
Conservation strategies for this species should account for the fragmented
nature of contemporary populations.