Identifying Rhabdomys museum specimens following taxonomic changes: use of short COI sequences

Abstract

The African four-striped grass mouse (Rhabdomys sp.) is a widespread rodent genus which is currently divided into two geographically distinct species. These rodents’ wide distribution range makes them perfect candidates for molecular studies related to adaptations to different habitats. Museum collections form valuable sources of samples for molecular analyses, but use of older classifications or mislabelling of specimens can be problematic. In this study, we attempt to use medium sized (~ 300 bp) cytochrome oxidase subunit I (COI) mitochondrial DNA fragments to correctly group Rhabdomys museum specimens into their now known taxonomic groups. Samples were sourced from four South African museum collections. We were able to group the majority of the specimens into their anticipated taxonomic groups, with 65 specimens identified as R. pumilio and 35 as R. dilectus. The phylogenetic grouping of the specimens largely correlated with work done by Du Toit et al. (2012). These results will facilitate the use of the selected specimens for a future study, which will focus on the genetic variation observed at selected adaptively linked genes, among Rhabdomys populations.