Stenonycteris lanosus (Thomas, 1906)

Don E. Wilson & Russell A. Mittermeier, 2019, Pteropodidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 16-162 : 89

49.

Long-haired Fruit Bat

Stenonycteris lanosus

French: Roussette a poil long / German: Langhaariger Flughund / Spanish: Stenonicterio piloso

Other common names: Long-haired Rousette

Taxonomy. Rousettus lanosus Thomas, 1906 ,

“Ruwezori East, at 13,000’ [= 3962 m].” Restricted by R. W. Hayman and colleagues in 1966 to “Mubuku valley,” Uganda.

K. Andersen in 1912 described Stenonycteris as a new subgenus of Rousettus to accommodate R. lanosus . For most ofits history, Stenonycteris remained a subgenus of Rousettus , but recent molecular systematics recovered lanosus in a phylogenetic position independent of Rousettus ; as a consequence, Stenonycteris has been recognized as a valid genus included in its own tribe Stenonycterini , with the single species S. lanosus (i.e. not inclusive of R. madagascariensis , as treated sometimes by some previous authors). Subspecies kempi (described as R. kempi by O. Thomas in 1909) is not included here until new data become available. Monotypic.

Distribution. Highlands of E Africa, highly fragmented distribution in W & S Ethiopia, S South Sudan, E DR Congo, Uganda, Kenya, Rwanda, Tanzania, and Malawi; most likely in Burundi.

Descriptive notes. Head—-body 114-173 mm, tail 9-25 mm, ear 19-25 mm, hindfoot 18-27 mm, forearm 85-95 mm; weight 94-162 g. Muzzle is long; eyes are large and blackish; ears are naked and dark brown, no basal ear patches; and antitragusis indistinct, with thickened margin. There are no epaulettes on adult males; back is medium to dark grayish brown or dark rusty brown, occasionally with dispersed paler hairs; hairs are unicolored; pelage is long and shaggy, with woolly underfur; and mid-dorsal underfur is 7-8 mm long, with scattered hairs up 16-18 mm extending up to halfway along forearms over uropatagium to wellfurred tibiae. Tail extends c¢. 16 mm beyond uropatagium. Venter is slightly paler than dorsum, sometimes with scattered paler hairs; adult males have longer,slightly stiffer hairs on neck and throat, but they do not form a ruff. Wings have a claw on second digit; membranes are dark brown, attaching to second toe or exceptionally between first and second toes; and no webbing occurs between toes. Skull is medium-sized and delicate; rostrum is relatively long; premaxillae are not fused; braincase is strongly deflected downward; zygomatic arches are very slender; there are eight palatal ridges of which four are interdental, and fifth is at level of posterior upper molars; and ridges 1-4 are undivided, ridges 5-7 are divided, and ridge 8 is very thin at posterior end of palate. Dental formulais12/2, C1/1, P 3/3, M 2/3 (x2) = 34. Upper and lower cheekteeth are relatively narrow in occlusal view, width of upper premolars and molars are ¢.50% their length or slightly more, and M* is not strongly reduced.

Habitat. Primarily montane tropical moist forests and mosaic of East African evergreen bushland and secondary Acacia (Fabaceae) wooded grassland at elevations of 500-4000 m (more commonly 1500-2500 m). The Long-haired Fruit Bat is found sporadically in drier lowland (Guineo-Congolese) rainforest, wetter and drier miombo woodland, East African evergreen and semi-evergreen bushland and thicket, and deciduous bushland and thicket of Acacia — Combretum (Combretaceae) .

Food and Feeding. Due to its rather delicate skull, diet of the Long-haired Fruit Bat probably consists of soft fruits, nectar, and possibly pollen. An individual tentatively identified as the Long-haired Fruit Bat has been reported feeding on flowers of Lobelia giberroa ( Campanulaceae ).

Breeding. Female lL.ong-haired Fruit Bats have one young per pregnancy. An adult female recorded from Malawi was lactating in late December. Pregnant females were found in Ethiopia in the beginning of May and middle ofJanuary. Pregnancies and males with scrotaltestes were reported in July in Pare Mountains, Tanzania. This might indicate an extended reproductive chronology, which might be bimodal.

Activity patterns. When flying in total darkness, Long-haired Fruit Bats use clicks (produced by their tongue) similar to echolocation clicks of Egyptian Rousettes ( Rousettus aegyptiacus ). Echolocation function of these sounds in the Long-haired Fruit Bat is not yet confirmed.

Movements, Home range and Social organization. [.ong-haired Fruit Bats roost in dark, damp caves and mine adits, where they can be exposed to low, even subzero, temperatures at night. To protect themselves, they roost in tight clusters of up to several hundred individuals.

Status and Conservation. Classified as Least Concern on The IUCN Red List (as Rousettus lanosus ). The Long-haired Fruit Bat has a wide distribution and presumably large population, and it is unlikely to be declining fast enough to have it listed in a higher category. Major threats include deforestation, disturbance of cave roosting sites, and possible overhunting for subsistence food.

Bibliography. Andersen (1912b), Bergmans (1994), Bergmans & van Strien (2004), Happold, M. (2013n), Hayman et al. (1966), Lavrenchenko et al. (2004), Monadjem, Howell et al. (2017), Nesi et al. (2013), Stanley & Goodman (2011), Thomas (1909), 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)

Distribution. Highlands of E Africa, highly fragmented distribution in W & S Ethiopia , S South Sudan , E DR Congo , Uganda , Kenya , Rwanda , Tanzania , and Malawi ; most likely in Burundi .