27.

Tiny Pipistrelle

Pipistrellus nanulus

French: Pipistrelle minuscule / German: Kleine Zwergfledermaus / Spanish: Pipistrela minuscula

Other common names: Dwarf Pipistrelle Bat, Tiny Pipistrelle Bat

Taxonomy. Pipistrellus nanulus Thomas, 1904,

“Efulen, Cameroons [= Cameroon].”

Recently collected specimens of P. nanulus from Ethiopia clustered genetically as sister to P. kuhlu, although identity of these specimens needs to be investigated further. Monotypic.

Distribution. W, C & E Africa from Senegal and Gambia to W Ethiopia and W & S Kenya; most records are throughout W Africa stretching E to SW Central African Republic and the Republic of the Congo (including Bioko I) with a few scattered records in DR Congo and W Central African Republic.

Descriptive notes. Head-body 38-47 mm, tail 21-32 mm, ear 7-11 mm, hindfoot 4-7 mm, forearm 24-31 mm; weight 2-7 g. Pelage of the Tiny Pipistrelle is dense. Dor sum is reddish brown (or light yellowish brown based on photographs of Ethiopian individuals), with unicolored hairs; venter is generally pale brown, with either unicolored or bicolored (pale brown with darker bases) hairs. Ears are short and rounded, and tragusis c.50% the heightof ears, has nearly straight anterior margin and smoothly convex posterior margin with pronounced basal lobe, and is rounded at tip. Wings are reddish brown similar to dorsum and usually without hind border, although translucent hind borderis occasionally present. Uropatagium is reddish brown, and tail protrudes slightly beyond membrane; postcalcarial lobe is narrow. Penis is enlarged, with hairy prepuce. Baculum is straight dorsally and curved ventrally closer to base, bilobed at top (making V-shape in dorsal view), wider at base but not bilobed (has small notch in middle), and is narrowed in middle between wide tip and base. Skull is small and gracile compared with other African Pipustrellus; braincase is relatively high and broad; interorbital region is comparatively broad; rostrum is comparatively short and broad; forehead region is moderately concave; I? is bicuspid, and I* is also bicuspid, well developed, and is almost as high as I*; P? is moderate to large in size and nearly within tooth row orslightly displaced lingually, being visible above gum; C' and P* do not touch; and lower molars are nyctalodont.

Habitat. Savanna and forested habitats, including riverine forests, tropical moist lowland forests, tropical dry forests, lowland savannas, and moist savannas from sea level up to elevations of ¢. 1833 m. The Tiny Pipistrelle might be associated with banana plantations, but this needs confirmation; it has been recorded in cocoa plantations on Bioko Island.

Food and Feeding. The Tiny Pipistrelle is insectivorous and probably forages near water. It has been observed foraging on insects over a damp wallow.

Breeding. Litter size is 1-2 young. Two pregnant Tiny Pipistrelles were recorded in January in Ghana, and a lactating female was captured in January in Ivory Coast.

Activity patterns. Tiny Pipistrelles are nocturnal; individuals have been observed foraging at daybreak. An individual was observed flying into a hollow branch that also contained a hive of bees. Call shape is FM/QCF, ending with slight downward droop. A call recorded in Maroua, northern Cameroon, had peak frequency of 65-5 kHz, minimum frequency of 45-6 kHz, knee frequency of 49-2 kHz, characteristic frequency of 45-8 kHz, and duration of 2-9 milliseconds.

Movements, Home range and Social organization. An “enormous” colony of Tiny Pipistrelles was found in the roof of a house on Bioko Island, although the exact number of individuals was unknown.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Tiny Pipistrelle faces no major threats, and it is widespread. Very little is known aboutits ecology; additional research is needed.

Bibliography. ACR (2018), Bates et al. (2013), Decheret al. (2016), Hill & Harrison (1987), Kangoyé et al. (2015), Kruskop et al. (2016), Manga Mongombe (2012), Monadjem & Fahr (2017a), Monadjem, Richards & Denys (2016), Monadjem, Richards, Taylor & Stoffberg (2013), Patterson & Webala (2012), Van Cakenberghe & Happold (2013).