Problems with the identification of southern African Chaerephon (Molossidae), and the possibility of a cryptic species from South Africa and Swaziland

Examination of recent collections of bats from KwaZulu-Natal (South Africa) and Swaziland, provisionally referred to Chaerephon cf. pumilus, reveals considerable variability in pelage colour (either greyish-brown or reddish-brown) and certain diagnostic characters of the skull and teeth from previous keys, in particular the degree of emargination of the anterior edge of the palate and the length of the maxillary toothrow. Based on the previously used key for southern African Molossidae, some specimens show diagnostic characters attributed to Chaerephon ansorgei and C. nigeriae, but in other characters, such as colour, forearm length, skull size, and relative mandible thickness, they clearly do not belong to either of these species. The obtained results suggest that the previously widely used key is inadequate for southern African Chaerephon, and a cryptic species, closely related to C. pumilus but with a partially or completely emarginated palatal condition, slightly larger forearm and skull size, better developed postaural crest, and high frequency of reddish-brown-coloured individuals, may occur in South Africa and Swaziland. A more extensive review is required to determine the relationships of this cryptic form to other African forms of the highly variable C. pumilus species-complex. A revised key to southern African Chaerephon species is presented.