Scotonycteris bergmansi, Hassanin, 2015

Don E. Wilson & Russell A. Mittermeier, 2019, Pteropodidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 16-162 : 81-82

34.

Bergmans’s Fruit Bat

Scotonycteris bergmansi

French: Scotonyctere de Bergmans / German: Bergmans-Harlekinflughund / Spanish: Scotonicterio de Bergmans

Taxonomy. Scotonycteris bergmansi Hassanin et al., 2015 ,

“ Central African Republic, Mbaéré-Bodingué National Park, Case of Kpoka, 3.90°N, 17.16°E, 430 m above sea level.”

Until recently, no differences were identified among S. zenkeri specimens from West Africa to eastern DR Congo; however, W. Bergmans in 1991 pointed out that distribution of S. zenkeri had several large gaps that were not related to lack of collecting efforts but to the species not being present in these areas. Four different clades were recovered in phylogenetic analyses using mitochondrial cytochrome-b and nDNA sequences, identified as three species: S. occidentalis , S. zenkeri , and S. bergmansi . These forms are now considered cryptic species formerly subsumed under S. zenkeri . Two subspecies recognized.

Subspecies and Distribution.

S.b.bergmansiHassaninetal,2015—SCameroon,SWCentralAfricanRepublic,EquatorialGuinea,Gabon,andRepublicoftheCongo.

S. b. congoensis Hassanin et al., 2015 — E DR Congo; possibly in Rwanda, Burundi, and NW Tanzania.

Descriptive notes. Head-body 65-85 mm (tailless), ear 12-17 mm, hindfoot 11- 14 mm, forearm 47-55 mm (on average, females slightly longer); weight 16-24 g. Bergmans’s Fruit Bat has white face markings on forehead and posterior corners of eyes; partially pale or white lips, especially around corners; short and slender muzzle; large eyes, with dark brown irises; naked ears with rounded tips; dark brown with lighter base, no basal ear patches; and moderately expansible lips. There are no epaulettes on adult males; dorsum is generally medium rusty brown to sepia-brown and speckled; hair has dark brown basal one-third, pale gray middles, and rusty brown tips; and pelage is dense,soft, woolly, and mid-dorsally 9-10 mm long. Central lower chest and belly are whitish to pale gray; flanks are medium to dark brown, not as sharply contrasting as in Hayman'’s Fruit Bat ( S. occidentalis ); and pelage of underparts is shorter and sparser than dorsum, with stiff hairs on chest and belly forming a collar. Wings have claw on second digits, flight membranes are light brown to dark greenish brown and reticulated, attaching to first toes; finger joints are not yellowish; and calcar is small. Skull is short and delicate; forehead region is almost straight; rostrum is relatively short; braincase is rounded; zygomatic width is relatively small, with relatively lightly built arches; palate is weakly concave; bony palate extends clearly beyond posterior teeth; and post-dental palate has straight, converging lateral margins. There are four thick, smooth palatal ridges, followed by 6-9 very thin, serrated and irregular ridges; ridges 1-3 are not divided, and ridge 4 is occasionally divided in middle. Upper incisors are relatively short and hardly curved, with blurred inner groove and without secondary cusps or serrated inner edges; and premolars and molars are rounded, almost oval in transverse section, and cusps relatively weak. Diploid number is 2n = 32, with ten pairs of meta- or submetacentric, four pairs of subtelocentric, and one pair of acrocentric chromosomes. X-chromosomeis submetacentric, and Y-chromosome is very small and does not seem to be biarmed.

Habitat. Degraded rainforests in low mountains and heavily disturbed low-elevation forests dominated by Hawmania liebrechtsiana ( Marantaceae ) in understory at elevations of 308-1100 m.

Food and Feeding. Fruit consumption by Bergmans’s Fruit Bats varied seasonally in DR Congo. Fruits from seven species in five families were eaten in the first wet season (September—November), four species in two families in the first dry season (December-February), ten species in eight families in the second wet season (March-May), and three species in three families in the second dry season (June-August). Various species of Ficus (Moraceae) were eaten in all seasons.

Breeding. A pregnant Bergmans’s Fruit Bat was collected in June in north-eastern DR Congo.

Activity patterns. No information.

Movements, Home range and Social organization. Movements and dispersal of Bergmans’s Fruit Bats appear limited by large rivers (e.g. Congo River).

Status and Conservation. Not assessed on The IUCN Red List. Bergmans’s Fruit Bat was included in Zenker’s Fruit Bat (S. zenkeri ), which was classified as Least Concern.

Bibliography. Bergmans (1991), Dowsett et al. (1991), Fahr (2013c), Gembu Tungaluna (2012), Hassanin etal. (2015), Primus et al. (2006), Van Cakenberghe et al. (2017).

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)

Subspecies and Distribution. S.b.bergmansiHassaninetal,2015—SCameroon,SWCentralAfricanRepublic,EquatorialGuinea,Gabon,andRepublicoftheCongo. S. b. congoensis Hassanin et al., 2015 — E DR Congo ; possibly in Rwanda , Burundi , and NW Tanzania .