56.

Sumatran Greater Bamboo Bat

Tylonycteris robustula

French: Vespertilion robuste / German: Sumatra-Bambusfledermaus / Spanish: Tilonicterio robusto

Other common names: Greater Bamboo Bat, Greater Flat-headed Bat

Taxonomy. Tylonycteris robustula Thomas, 1915,

“Upper Sarawak, Borneo,” Malaysia.

Tylonycteris robustula was previously considered to include 7. malayana as a subspecies, and also populations of the recently described T. tonkinensis, but both were elevated to species status based on morphological and genetic data. Internal taxonomy untested, as only populations from Sumatra have been genetically compared to other Tylonycteris; further studies are needed. Monotypic.

Distribution. Philippines (Luzon, Negros, Calauit, and Palawan Is), Sumatra, W & NW Borneo, Java, Bali, Lombok, Timor, and Sulawesi (including Peleng I).

Descriptive notes. Head-body 40—44-9 mm, tail 28-31 mm, ear 9-611 mm, hindfoot 6-7-6 mm, forearm 25-29-8 mm; weight 5-7-8 g. Head is dorso-ventrally flattened and broadened. Fur is smooth and sleek with a somewhat glossy appearance; dorsal pelage is dark brown to dark grayish brown, whereas ventral pelage is slightly paler. Membranes are dark brown. Ears are subtriangular, relatively long with a broadly rounded tip; tragusis short and blunt. Base of thumbs and soles of hindfeet have well-developed rounded fleshy pads for gripping smooth surfaces. Wing membrane attaches at base of metatarsus; uropatagium extends to tip oftail, and calcar is over halfway to tail from ankle. For skull description, see the Malayan Greater Bamboo Bat (71. malayana), as the two species have not yet been well differentiated based on skull morphology.

Habitat. Both intact and disturbed forest habitats with abundant bamboo. Recorded at elevations up to ¢. 1000 m in Borneo, at 711 m in Sumatra, and in lowland regions from sea level to ¢. 500 m in the Philippines.

Food and Feeding. The Sumatran Greater Bamboo Batis insectivorous.

Breeding. Twins are born once a year.

Activity patterns. Sumatran Greater Bamboo Bats roost in hollowed internodes of bamboo. They seem to favor larger dead stems than the Sunda Lesser Bamboo Bat ( 1. pachypus).

Movements, Home range and Social organization. The Sumatran Greater Bamboo Bat roosts in small groups, with groups of 1-7 recorded in the Philippines.

Status and Conservation. Classified as Least Concern on The IUCN Red List, although most of its distribution is now attributed to a different species, so a reevaluation is needed.

Bibliography. Bates, Francis, Rosell-Ambal & Heaney (2008), Heaney & Alcala (1986), Heaney et al. (2016), Huang, J.C.C. et al. (2014), Rahman etal. (2011), Tu Vuong Tan, Csorba etal. (2017).