Phylogeny, phylogeography and geographical variation in the C rocidura monax ( S oricidae) species complex from the montane islands of T anzania, with descriptions of three new species

We assess morphological and multilocus genetic variation among 11 isolated montane populations of white‐toothed shrews from T anzania that have been referred to either C rocidura monax   T homas or C . montis   T homas. The montane sites we sampled represent ‘sky‐islands’ from two geologically distinct archipelagos ( N orthern H ighlands and the E astern A rc M ountains) and are a significant component of the E astern A fromontane B iodiversity H otspot. We used multivariate analyses of morphometric traits and phylogenetic and species‐delimitation analyses of multilocus DNA sequence data to assess species‐level diversity. Our species delimitation analyses included a novel, pairwise validation approach that avoids potential biases associated with specifying a guide tree. These analyses reveal several distinct lineages, which we treat as six allopatric species. Each species is restricted to one, two or four mountains. We use available names to recognize C . monax , C . tansaniana   H utterer and C . usambarae   D ippenaar, while naming and describing three new species. Our results demonstrate the effectiveness of combining morphological and genetic data to uncover and describe hidden diversity in a cryptic mammalian system. © 2015 The Linnean Society of London