Dobson, 1872
Theobald's Tomb bat
External characters (Table 21)
This is a medium-sized Taphozous which is distinguished from T. melanopogon (Tme3) by the greater length of forearm which averages 72.7 mm (71.0-76.0 mm). Unlike T. nudiventris (BW7) and T. saccolaimus , there is no gular sac in either sex, although according to Khajuria, 1979, there is a glandular area behind the chin even in females and subadults. In older male specimens, a throat patch of darker brown hairs is present (Khajuria, 1979); this is not present in the male holo- and topotype specimens of secatus in the collection of The Natural History Museum, London. The pelage of T. t. secatus is grey brown on the dorsal surface, with the hair bases paler; it is a uniform grey on the ventral surface. Unlike T. melanopogon , the fur is strictly limited to the body and is not present on any part of the wings above, or on the interfemoral membrane, above and below. The membranes are a uniform dark brown and the wings are attached to the tibiae; each wing has a well developed radio-metacarpal pouch. In contrast to T. nudiventris (Tnu1), there is no naked area on the posterior back and abdomen and the feet are without prominent pale hairs. The ears are large, exceeding those of T. saccolaimus in size; they are dark brown in colour. The lower lip is scarcely grooved.
Cranial characters
The skull, with an average condylo-canine length of 22.5 mm (21.9-23.4 mm) is significantly larger than that of T. melanopogon but has a similar morphology. In contrast to T. nudiventris and T. saccolaimus , the zygomata are not widely flared and the lambda does not form the most posteriorly projecting part of the braincase. The basisphenoid pits are well developed; they greatly exceed those of T. nudiventris in size and are relatively larger than those of T. saccolaimus . The tympanic bullae are typical of the nominate subgenus with the antero-internal border incomplete and with the main body of each cochlea clearly visible; in T. saccolaimus , the bullae are completely ossified. The mandible is unremarkable.
Dentition
Upper toothrow length (C-M3) averages 10.0 mm (9.4-10.5 mm). The dentition is similar to, but significantly larger than that of T. melanopogon .
Variation
Specimens from India are referred to T. t. secatus . According to Thomas, 1915e, in secatus the wings and interfemoral membrane are without trace of fur; in the nominate form, T. t. theobaldi , some hairs are present on these membranes. There is no apparent difference in size between the two taxa.