Eonycteris robusta, G. S. Miller, 1913

Don E. Wilson & Russell A. Mittermeier, 2019, Pteropodidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 16-162 : 84-85

40.

Philippine Dawn Bat

Eonycteris robusta

French: Eonyctere des Philippines / German: Philippinen-Langzungenflughund / Spanish: Eonicterio de las Filipinas

Other common names: Philippine Nectar Bat

Taxonomy. Eonycteris robusta G. S. Miller, 1913 ,

“cave at Montalban [Rizal Province], Luzon, Philippine Islands.”

Eonycteris robusta is occasionally included as a subspecies of E. major , although it is morphologically distinct based on cranial measurements and is generally recognized as a distinct species. Monotypic.

Distribution. Philippines on Luzon, Polillo, Lubang, Marinduque, Catanduanes, Samar, Maripipi, Biliran, Leyte, Negros, Bohol, Siargao, and Mindanao Is.

Descriptive notes. Head-body ¢. 107- 127 mm, tall 20-28 mm, ear 19-23 mm, hindfoot 23-25 mm, forearm 67-82 mm; weight 56-80 g. The Philippine Dawn Bat has elongated and narrow snout and head, long pointed tongue, and no claw on second digit of wing. Males are typically larger than females and have ruff of elongated hairs around neck that is often yellowish. Muzzle is longer and more downturned than in the Lesser Dawn Bat (FE. spelaea ), and it lacks paired anal glands, has somewhat longer tail, and averages a little larger in size. Dorsal pelage ranges from dark gray to silvery gray relatively evenly from head to rump, often tinged with yellow or orange around neck region. Ventral pelage is generally lighter than dorsum. Ears are bluntly pointed, medium in length, and brownish; eyes are large, with dark reddish-brown irises. Wings,legs, and uropatagium are dark brown. Arms are lightly covered in brown hairs. Tail is moderately long, sparsely covered with hairs, and dark brownish; uropatagium attaches at base oftail and short keel at ankles, giving V-shaped gap where tailis. 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 braincaseis heavily deflected downward. Teeth are sharp and not as reduced as in some nectarfeeding bats, but molars and premolars have considerably reduced cusps and are narrow and elongated. Upper incisors are small and triangular, C' is relatively large, and C, 1s small, simple, and heavily curved outward. Chromosomal complement has 2n = 36 and FN = 66(?).

Habitat. Largely undisturbed primary lowland forests and some secondary and disturbed forest habitats from sea level up to elevations of ¢. 1100 m (more commonly lower elevations).

Food and Feeding. No information.

Breeding. Female Philippine Dawn Bats have one young per pregnancy.

Activity patterns. Day roosts of Philippine Dawn Bats are located in caves, particularly limestone caves, although they might roost in rocky banks and rock crevices.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Near Threatened on The IUCN Red List. The Philippine Dawn Bat is not particularly common throughout its distribution, although it is common in some lowland regions surrounding roost caves. It seems to be sensitive to habitat disturbance and destruction and is absent from agricultural and urban regions. General deforestation and cave disturbance are most likely main threats, and it might be threatened by increased habitat loss through deforestation across the Philippines. Hunting and mining operations are additional threats.

Bibliography. Heaney (2001), Heaney & Rabor (1982), Heaney, Balete, Dolar et al. (1998), Heaney, Balete & Rickart (2016), Heaney, Gonzales et al. (1991), Heaney, Tabaranza et al. (2006), Ingle & Heaney (1992), Ong, Rosell-Ambal, Tabaranza, Walston et al. (2008), Rickart, Heaney, Heideman & Utzurrum (1993), Rickart, Heaney & Rosenfeld (1989), Rickart, Mercier & Heaney (1999), Tababa 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. Philippines on Luzon, Polillo, Lubang, Marinduque, Catanduanes, Samar, Maripipi, Biliran, Leyte, Negros, Bohol, Siargao, and Mindanao Is.