A New Species of Horseshoe Bat (Chiroptera: Rhinolophidae) from Mount Namuli, Mozambique

Abstract

The ecology of the high-altitude mountains of northern Mozambique is understudied in comparison to surrounding countries. A series of biological surveys have focused on filling this data gap, with Mount Namuli in Zambezia Province one of the focal sites of these expeditions. A biological survey of Mount Namuli in 2009 resulted in the collection of five specimens of a horseshoe bat species (Rhinolophidae) that is here described as a new species from Mozambique. Morphologically, the new species is very similar to Rhinolophus maendeleo Kock, Csorba and Howell, 2000 of the adami-group, but lacks some key morphological characters of this group (large ears, narrow skull, long palate). Molecular reconstructions clearly suggest the new species belongs to the capensis-group, but no members of the adami-group were included in this analysis (due to lacking data). It is thus unclear whether this unexpected phylogenetic position reflects morphological convergences between members of the adami- and capensis-groups, or whether the morphology-based adami-group should be reconsidered. The new species and R. maendeleo share similar external and craniodental measurements, but can be distinguished based on a number of key characters. These include the presence of a bony bar forming the interorbital foramena, rostrum shape, ear length and highly differing bacular morphologies. It also differs from the genetically closely related R. denti Thomas, 1904, R. swinnyi Gough, 1908 (including two recently described cryptic species) and R. simulator Andersen, 1904 by non-overlapping external and cranial measurements. The new species echolocates at a mean peak frequency of 76.9 kHz and shows an affinity to forest habitats, which are highly threatened in the surrounding region. It joins other coastal and montane forest endemics in defining the bat fauna of south-eastern Africa.