(Temminck, 1840)
Van Hasselt's bat
External characters (Table 72)
This species, with an average forearm length of 39.3 mm (37.2-40.3 mm), is comparable in size to M. horsfieldii . The feet are long and slender; they greatly exceed half the length of the tibiae. The ears are rather narrow with the tips narrowly rounded-off. The tragus of each ear is narrow, half or less the height of the pinna. The pelage on the dorsal surface is dark brown with the hair tips slightly paler than the roots. On the ventral surface, they are dark brown/ black at the roots, with the tips a paler grey. The wings are attached to the ankles or tibiae; in M. horsfieldii they are attached to the outer metatarsal of each foot; otherwise, they are similar in structure. The interfemoral and wing membranes are a uniform dark brown.
Cranial characters
The skull (BW25b), with an average condylo-canine length of 14.2 mm (14.0-14.6 mm) is more robust than that of M. horsfieldii (Fig. 145). The braincase is bulbous, broad and almost spherical in outline. The sagittal crest is visible posteriorly and the lambdoid crests are present. The lambda forms the most elevated part of the skull and the supraoccipital just forms the most posterior part. The zygomata are moderately robust. The rostrum is robust and broad; it is less depressed than that of M. horsfieldii ; there is a slight post nasal depression on account of the very elevated anterior part of the braincase. The coronoid process of each half mandible is very well developed and greatly exceeds the canine in height; its morphology is essentially similar to that of M. horsfieldii .
Dentition
- Upper toothrow length (C-M3) averages 5.9 mm (5.8-6.0 mm). The upper canine is robust, broad and greatly exceeds the third premolar (PM4) in height (BW25b); it is about equal to it in crown area. The second upper premolar (PM3) is minute or occasionally absent; it is usually about one quarter the crown area of the first (PM2); PM2 and PM4 are in contact or nearly so.
- The lower canine exceeds the third lower premolar (pm4) in height and crown area. The second lower premolar (pm3) is very small; it is one third to one half the crown area of the first (pm2) and is usually situated in the toothrow but may be displaced internally.
Variation
Specimens from India and Sri Lanka are referred to the nominate race M. h. hasseltii .