Hypsugo crassulus (Thomas, 1904)

Broad-headed pipistrelle

Pipistrellus crassulus Thomas, 1904: 206; Efulen, Cameroons (= Cameroon).

New material

HZM.1.40190, ♂, 4 August, 2012, Forest Trails, Lekoumou, 2°45.767’S, 13°36.365’E. This is the first authenticated record for Congo (Appendix I). According to Happold and Happold (2013), this species is widely distributed but localised in Africa, not uncommon in suitable habitats.

Description

A small, nondescript, species with a short forearm length of 26.7 mm (Table 2) but a robust body. The dorsal pelage, wing and interfemoral membranes are dark. The ventral pelage appears to be dark. In the ear, the tragus is tall and relatively narrow; the anterior border is straight, the posterior border is rounded and there is a well developed basal lobule (Fig. 8C). The skull has a greatest length of 13.80 mm (Table 3). In lateral profile, the rostrum runs smoothly to the braincase with only the slightest indication of a concavity in the interorbital region; the braincase is relatively flat and is highest at its most posterior point (Fig. 10A). The first upper incisor (I 2) is tricuspid; the second (I 3) is unicuspid but with a well developed cingulum, it attains half the height of I 2 (Fig. 10A). The first upper premolar (P 2) is minute and displaced internally such that the canine and second premolar (P 4) are nearly in contact (Fig. 10A). The first lower premolar (P 2) is between half and two-thirds the crown area and two-thirds the height of the second (P 4) (Fig. 10A). The baculum, which is 3.9 mm in length, has a long, thin, pointed shaft, which is curved when viewed laterally, and a bilobate base (Fig. 11A); this compares well with the baculum of the holotype of crassulus illustrated in Hill and Harrison (1987: Figure 7e).

Taxonomic notes

Currently there are no subspecies recognised (Heller et al., 1994; Happold and Happold, 2013).