Specific status of populations in the Mascarene Islands referred to Mormopterus acetabulosus (Chiroptera: Molossidae), with description of a new species

03 February 2010

On the basis of molecular and morphological evidence, Mormopterus acetabulosus, hitherto considered an endemic to the Mascarene Islands (Mauritius and La Re´union), is shown to comprise 2 closely related taxa. The holotype of M. acetabulosus is from Mauritius and the new taxon described herein is from La Re´union. M. acetabulosus from Mauritius is notably larger than members of this genus from La Re´union, and several soft-part and cranial characters distinguish these 2 taxa. This conclusion is supported by examination of mitochondrial DNA control region data for 141 bats, which shows these 2 groups to be reciprocally monophyletic, separated by an average of 5.01% uncorrected sequence divergence. Two nuclear intron regions (7th intron of the beta fibrinogen gene and thyrotropin) also were included, but showed limited genetic variation and no fixed differences between the 2 taxa. These 2 species of Mormopterus are common on Mauritius and La Re´union, often living in caves or synanthropically, and are not considered a conservation concern.