(Temminck, 1840)
Bamboo bat; Flat-headed bat; Club-footed bat
External characters (Table 88)
This is a minute bat with an average forearm length of 27.6 mm (26.1-29.0 mm). The head is characteristically flattened (Tpa1) with the nostrils projecting forwards and slightly downwards (Fig. 190). The ears are triangular with broadly rounded tips; the tragus of each is short and broad (Tpa2). The soles of the feet and the base of the first digits (thumbs) have broad fleshy circular pads (Fig. 196). Like T. robustula (Tro1), the wings are short with the third, fourth and fifth metacarpals about equal in length. The interfemoral and wing membranes are uniformly dark brown (Tpa3). The pelage is fine and dense. In individuals from peninsular India, it is golden brown above on the head and upper back, darker brown on the lower back. The throat is a pale golden brown and the belly is slightly darker (Tpa4). The baculum is minute; it has a simple tip and a slightly broader base (Fig. 192).
Cranial characters
The skull (Fig. 191) is small with an average condylo-canine length of 10.6 mm (10.0-11.3 mm). The braincase and rostrum are extraordinarily flattened and relatively broad. The breadth of the braincase exceeds twice the occipital height. The postorbital constriction is broad and the rostrum is also short and broad, with a distinct supraorbital projection above each orbit (this is relatively smaller than that of T. robustula ) (Fig. 197). The nasal notch is smaller than that of T. robustula ; it does not extend posteriorly to the level of the infraorbital foramina. The zygomata are widely flared. The sagittal crest is absent. The mesopterygoid space and basioccipital are broad; the tympanic bullae are small. The horizontal ramus of each half mandible is very delicate; the coronoid process is relatively large, the condyle and angular process minute.
Dentition
- Upper toothrow length (C-M3) averages 3.7 mm (3.4-4.2 mm) in length. The first upper incisor (I2) is narrow and bicuspidate; the second (I3) is unicuspid and equal in height to the outer cusp of I2 (Fig. 194). There is a short diastema between I3 and the upper canine which has a distinct posterior secondary cusp. The upper premolar (PM4) is relatively small with a crown area about half that of M1 (Fig. 193). M2 exceeds M1 in breadth; it has a well developed protocone. M3 is without a metastyle but is otherwise not greatly reduced; its crown area exceeds half that of M2.
- The three lower incisors are tricuspidate. The lower canine is relatively weak, scarcely exceeding the protoconid of m2 in height. The first (pm2) and second (pm4) premolars are about equal in size and are tightly compressed in the toothrow; the anterior part of pm2 is situated on the posterior cingular cusp of the lower canine. In m1 and m2, the talonid exceeds the trigonid in size; in m3 they are about equal in crown area.
Variation
Specimens from peninsular India are referred to T. p. aurex ; they have golden brown pelage and a relatively large skull (condylo-canine length = 11.0 mm, 10.6-11.3 mm). Those from north-east India are referred to T. p. fulvidus and have a more drab brown appearance and a smaller skull (CCL= 10.4 mm, 10.0-10.8 mm).