Eonycteris major, K. Andersen, 1910

Don E. Wilson & Russell A. Mittermeier, 2019, Pteropodidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 16-162 : 84

39.

Greater Dawn Bat

Eonycteris major

French: Grand Eonyctére / German: Borneo-Langzungenflughund / Spanish: Eonicterio grande

Taxonomy. Eonycteris major K. Andersen, 1910 ,

“MtDulit, N. Borneo [ Sarawak, Malaysia], 2000’ [= 610 m].”

Some researchers included E. robusta as a subspecies of E. major , but they are morphologically distinct based on cranial features and generally recognized as distinct species. Individuals from the Mentawai Islands might represent a large form of E. spelaea or an undescribed subspecies of E. major additionalresearch is needed. Monotypic.

Distribution. Borneo and Mentawai Is (Sipora and North Pagai).

Descriptive notes. Head-body 124-130 mm, tail 18-0-26- 9 mm, ear 18- 2-21 mm, hindfoot 14-6-15- 5 mm, forearm 61-85 mm; weight 91-98 g. The Greater Dawn Bat has elongated narrow snout and head, long pointed tongue, and no claw on second digit of wing. Muzzle is longer and more downturned than in the Lesser Dawn Bat ( E. spelaea ), and it also lacks paired anal glands, has darker pelage, somewhat longer tail, and larger average size. Males seem larger on average than females. Dorsal pelage is dark blackish brown and relatively uniform across head, neck, back, and arms. Ventral pelage is paler blackish brown. Ears are bluntly pointed, medium in length, and dark brown; eyes are large, with dark reddish-brown irises. Wings, legs, and uropatagium are blackish brown. Arms are lightly covered in brown hairs. Tail is short, covered sparsely with hairs, and dark brownish; uropatagium attaches at base of tail and short keel at ankles, giving V-shaped gap where tail is. Second digit of wing lacks a claw, and metacarpals offifth digit are much shorter than metacarpals of third digit; skin over wing bones is pigmented. Skull is elongated, with long rostrum; anterior premaxillae are in contact or slightly divided; and braincase is heavily deflected downward. Teeth are sharp and not as reduced as in some nectarfeeding bats, although molars and premolars have considerably reduced cusps and are narrow and elongated. Upper incisors are small and triangular, C' is relatively massive (larger than in the Lesser Dawn Bat), and C, is small, simple, and heavily curved outward.

Habitat. Primarily primary forests (largely confined to higher elevations) and lowland dipterocarp forest from sea level up to elevations of ¢. 1100 m. Greater Dawn Bats occur sympatrically with Lesser Dawn Bats but in very low densities when sympatric.

Food and Feeding. The Greater Dawn Bat feeds on nectar and pollen of various flowering plants, probably feeding heavily on some agriculturally important species (e.g Musa , Musaceae and Durio , Malvaceae ).

Breeding. No information.

Activity patterns. Greater Dawn Bats are nocturnal, foraging throughout the night and roosting throughout the day. They roost in caves and occasionally hollow trees.

Movements, Home range and Social organization. Greater Dawn Bats are gregarious and roost in colonies of several hundred individuals. They share roosts with Lesser Dawn Bats and probably Geoffroy’s Rousettes ( Rousettus amplexicaudatus ). Fifteen to 20 earwigs (Scizochelisoches sp.), possibly feeding on ectoparasites, were found ventrally near base of the tail of a Greater Dawn Bat in Borneo.

Status and Conservation. Classified as Data Deficient on The IUCN Red List. The Greater Dawn Batis considered rare throughoutits distribution and occurs at low population densities, being known from relatively few records. It might be sensitive to roost disturbance and deforestation due to its strong association with primary forests. Despite its low densities, it might not be threatened, but considerable research is needed to understand its ecology,life history, and threats.

Bibliography. Bates, Bumrungsri, Francis, Gumal & Sinaga (2008), Corbet & Hill (1992), Kumaran, Ketol et al. (2016), Kumaran, Khan & Abdullah (2005), Payne et al. (1985), Phillipps & Phillipps (2016), Wilting et al. (2012).

Figures

32. Zenker’s Fruit Bat (Scotonycteris zenkeri), 33. Hayman’s Fruit Bat (Scotonycteris occidentalis), 34. Bergmans’s Fruit Bat (Scotonycteris bergmansi), 35. Short-palated Fruit Bat (Casinycteris argynnas), 36. Pohle’s Fruit Bat (Casinycteris ophiodon), 37. Campo-Ma’an Fruit Bat (Casinycteris campomaanensis), 38. Lesser Dawn Bat (Eonycteris spelaea), 39. Greater Dawn Bat (Eonycteris major), 40. Philippine Dawn Bat (Eonycteris robusta), 41. Geoffroy’s Rousette (Rousettus amplexicaudatus), 42. Bare-backed Rousette (Rousettus spinalatus), 43. Leschenault’s Rousette (Rousettus leschenaultin), 44. Linduan Rousette (Rousettus linduensis), 45. Sulawesi Rousette (Rousettus celebensis), 46. Egyptian Rousette (Rousettus aegyptiacus), 47. Malagasy Rousette (Rousettus madagascariensis), 48. Comoro Rousette (Rousettus obliviosus), 49. Long-haired Fruit Bat (Stenonycteris lanosus)

Distribution. Borneo and Mentawai Is (Sipora and North Pagai).