6.

Dark Thick-thumbed Bat

Glischropus aquilus

French: Pipistrelle sombre / German: Dunkle Dickdaumenfledermaus / Spanish: Pipistrela de Sumatra

Taxonomy. Glischropus aquilus Csorba et al., 2015,

“Sukabanjar village, Lampung, Sumatra, Indonesia, 4°56’S, 103°52°E, 768 m a.s.l.”

This species appears to be sister to G. tylopus, based on genetic data. Monotypic.

Distribution. Known only from type locality in SW Sumatra.

Descriptive notes. Head-body 35-4 mm, tail: 38: 8 mm, ear 11 mm, hindfoot 6-2 mm, forearm 32-2 mm; weight 4-8 g holotype). The Dark Thick-thumbed Bat is distinguished from its congeners by its darker pelage and ears. Dorsal pelage is uniformly dark brown (individual hairs dark brown with a lighter brown tip), while ventral pelage is a lighter medium brown (individual hairs dark brown for basal two-thirds and medium brown for distal one-third). Ears are blackish, wide, and broadly rounded, and tragus is relatively narrow and bluntly pointed. Plagiopatagium is attached to base of toe and calcaris short (extending to less than one-half the free edge of uropatagium). Thumb has a large pinkish pad as in other Glischropus, which is oval-shaped; soles of feet are pink and fleshy. Penis is dorso-ventrally flattened, and proximal one-half is practically naked, while distal one-half is very hairy (hairs are stiff and whitish on dorsal surface and around glans). In comparison to the Javan Thick-thumbed Bat ( Glischropus javanus) and the Common Thick-thumbed Bat ( G. tylopus), the Dark Thick-thumbed Bat has a deeper rostrum, more elevated frontal region, and higher occipital region. This species is most similar to the Indochinese Thick-thumbed Bat ( G. bucephalus), although it shows greater post-dental width, as well as having a less swollen braincase and a gradually narrowing interorbital region. I? is bicuspid; I’ is one-halfthe height of I; P? is as large as I? basally and is partly displaced from tooth row and visible in lateral view; lower molars are nyctalodont.

Habitat. Collected in secondary forest near a bamboo stand and a small stream at an elevation of 768 m.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. Like other species in the genus, Dark Thick-thumbed Bats probably roost in dead bamboo stalks, rock crevices, and banana leaves, when available.

Movements, Home range and Social organization. No information.

Status and Conservation. Not assessed on The [UCN Red List. The Dark Thick-thumbed Bat is known only from a single specimen. Further research is needed to provide a clear picture of the species’ conservation status.

Bibliography. Csorba et al. (2015), Huang, J.C.C. et al. (2014).