Multi-gene phylogeography and ecological patterns within the South African Bathyergidae: Implications for systematics. Multi-gene phylogeography and ecological patterns within the South African Bathyergidae: Implications for systematics

The family Bathyergidae (comprising six genera) is a group of subterranean rodents endemic to sub-Saharan Africa. Our understanding of the evolution and species richness of the South African bathyergid genera Georychus, Bathyergus and Cryptomys is poor, leading to the protected status of the species they contain listed as “Least Concern” by the IUCN Red List of Threatened Species. In contrast, genetic data suggests several cryptic species present in these genera. To explore genetic and ecological distinctiveness and evaluate taxonomic richness across the ranges of Georychus, Bathyergus (and to a lesser degree Cryptomys), as well as evaluate possible phylogeographic scenarios which have historically influenced evolutionary patterns, we employed four protein coding markers (one mitochondrial and three nuclear) along with a distribution wide sampling schemes and large sample sizes. In addition, possible ecological differences among the different intra-generic clades were explored. Phylogeographic patterns within and between the three bathyergid genera bear signatures of past climatic and geological events, and it appears that major environmental changes since the middle Miocene were instrumental in fragmenting their distributions and causing isolation and divergence. Along with protracted periods of separation, it appears that ecological differences exist between the clades. This corroborates findings that several cryptic species may be present within the South African bathyergidae.