A new paper by Gabriele Sgarlata and colleagues has just been released in the American Journal of Primatology on the genetic and morphological diversity of mouse lemurs in Northern Madagascar.
Several years of sample collection across forests of Northern Madagascar, together with genetic data, allowed us to update the species distribution of several endangered mouse lemur species. We found that the distribution of Microcebus tavaratra extends beyond the river Manambato which was thought to be its southermost limit. We also find individuals that appear to belong to the species Microcebus arnholdi, a species which was thought to only exist in Montagne d’Ambre and one isolated forest in the NW of Madagascar. Furthermore, we provide the first evidence for a new mitochondrial clade which could correspond to a new putative mouse lemur species or a divergent set of populations. The putative species status needs to be confirmed or rejected with additional genomic data. We also found that in the case of two mouse lemur species and associated to either dry (M. tavaratra) or humid (M. arnholdi) habitat, a simple morphological trait (tail length) was sufficient to discriminate between the two species. This trait might be related to adaptation to habitat type. Ultimately, this study provides further evidence that humid forests that are currently separated in Northern Madagascar were most likely connected and that this region was likely covered with humid forests in the not so distant past.
You can find the published version here: