(E. Geoffroy, 1818)
Egyptian Free-tailed bat
External characters (Table 58)
This species (Tae1) is essentially similar externally to T. teniotis but distinctly smaller with an average forearm length of 48.2 mm (46.0-52.3 mm). The ears are separated on the forehead. The tragus of each ear is small, although relatively larger than that of T. teniotis , with a rather square outline and with a small angular projection from its posterior border; the antitragus is well developed. The pelage is fine and dense, shorter on the belly. It is variable in colour, even amongst individuals from the same colony. On the dorsal surface, it ranges from dark buffy brown to dark clove brown; the tips and roots are uniformly coloured. It is paler on the ventral surface (Tae2). The feet, like those of Tadarida plicata , are hairy (Fig. 121); the membranes are essentially naked.
Cranial characters
The skull, with an average condylo-canine length of 17.9 mm (17.1-18.8 mm) is smaller and less elongated than that of T. teniotis (Tte1). The postorbital region is notably less protracted and the zygomata more widely flared anteriorly. The braincase is smooth, broad and distinctly flattened; the sagittal crest is absent. The dorsal profile is comparable to that of T. teniotis (Tte4); nearly straight from the back of the nasal aperture to the lambda, but with a slight convexity over the anterior two-thirds of the braincase and with an elevated portion posteriorly. The palate is less elongated than that of T. teniotis (Tte3) but the premaxillae are similarly not co-ossified; the anterior palatal emargination extends back behind the level of the front of the upper canines. Shallow basisphenoid pits are present. In each half mandible, the posterior border of the coronoid process is relatively shorter than that of T. teniotis .
Dentition
- The teeth are smaller than those of T. teniotis with an average upper toothrow length (C-M3) of 7.4 mm (7.1-7.8 mm). They are essentially similar in morphology except that the first upper premolar (PM2) is smaller and sometimes partially displaced externally from the toothrow; it is occasionally absent; there is a narrow gap between the canine and the second upper premolar (PM4). M3 is relatively narrower in antero-posterior diameter.
- In the lower dentition there are only two pairs of lower incisors, although Hill in Chaturvedi, 1964 notes that some aberrant individuals may have three pairs, as in T. teniotis .
Variation
Wroughton, 1919 distinguished T. a. thomasi from Gujarat from T. a. gossei from Maharashtra on the colour of the fur, paler near 'seal brown' versus darker near 'clove brown'. However, Brosset, 1962c considered this character only as individual variation and Kashyap, 1978 lists the extreme variability found amongst individuals from the same colony. Sinha, 1970 included gossei as a synonym of thomasi ; a view followed here. The two specimens in the Natural History Museum, London from Kashmor, Pakistan were assigned to the taxon sindica by Wroughton, 1919; they are larger than those from India; further research may show that they should be treated as a distinct subspecies T. a. sindica .