Like most bats in the family Pteropodidae, M. pusillus does not rely on echolocation as a mode of perception. Instead, this bat relies mostly on sight and sound to percieve its environment and communicate. Males have enlarged vocal cords for emitting shrill calls. Males also open and vibrate their shoulder epaulettes to attract females.
Communication Channels: visual ; acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
Micropteropus pusillus is not listed on the CITES appendices or the United States Endangered Species Act list. On the IUCN Red List, M. pusillus is listed as Lower Risk/Least Concern (LR/lc).
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Micropteropus pusillus, like other fruigivorous bats, can be a nuisance to humans. In some areas, fruit crops are damaged by bats during feeding.
Negative Impacts: crop pest
Because M. pusillus is a pollinator of Kigelia pinnata, the sausage tree owes at least part of its continued existence to the bat. This is of importance for humans interested in preserving biodiversity.
Micropteropus pusillus is one of the species that pollinates the flowers of Kigelia pinnata, the sausage tree. The flowers open at dusk and emit an unpleasant odor that attracts the bat. Sausage tree flowers hang on thick stalks and have deep floral cups. The male and female parts of the flower are confined to the basal region. The bat lands on the lip of the flower and pushes its head into the floral cup to drink nectar, thereby covering its head and shoulders with pollen. The flowers close at about 11pm, when the bat is no longer present. Micropteropus pusillus may also pollinate flowers of other species of plants.
Ecosystem Impact: pollinates
Micropteropus pusillus is fruigivorous and nectarivorous. The fruits of Ficus capensis and F. vallischoudae comprise a large part of the diet. Also eaten are fruits from Anacardium occidentale, Annona chrysophila, and Psidium guajava. This bat also feeds on fallen fruit, and often visits mango groves and banana plantations.
Micropteropus pusillus also eats flowers, pollen, and nectar from Kigelia pinnata (the sausage tree), K. africana, Spathodea campanulata, Adansonia digitata, Maranthus polyandra, and Parinari polyandra.
Plant Foods: fruit; nectar; pollen; flowers
Primary Diet: herbivore (Frugivore , Nectarivore )
Micropteropus pusillus, the dwarf epauleted bat, has an Ethiopian distribution. It occurs in western, southwestern, and central Africa. The northern boundary of its range is set by the Sudanian and Ethiopian highlands, the eastern boundary is set by the Ethiopian highlands. The southern limit of the range is within the North Zambesian woodland. Micropteropus pusillus is found in Senegal, southern Sudan and Ethiopia, and south to Angola and southern Zaire.
Biogeographic Regions: ethiopian
Micropteropus pusillus occurs in a variety of habitats. It is commonly found in savannah woodlands, vegetation that fringes forests, and coastal areas. It also inhabits swamp forests, grasslands, and bushlands.
Micropteropus pusillus prefers to roost in dense vegetation. Roosts are located 3 to 6 meters above the ground shrubs or in the lower parts of trees.
Range elevation: 50 to 800 m.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: savanna or grassland ; forest
Wetlands: swamp
The lifespan of M. pusillus is undocumented.
Micropteropus pusillus is one of the smaller members of the suborder Megachiroptera. On the bat's dorsal surface, the pelage is varying shades of brown and moderately long and thick. Hair on the ventral surface is more sparse, shorter, and of lighter tone. The pelage is soft, covering the upper arm and part of the forearm, and extends onto the wing. Small white to yellowish colored tufts of hair are present at the base of the ears.
In appearance, M. pusillus resembles pteropodids of the genus Epomophorus, except the lips are not as expansible, and the muzzle and ears are shorter. It has a round head and large eyes, and ears that are rounded at the tip. The tail is usually imperceptible in the uropatagium.
Micropteropus pusillus exhibits secondary sexual dimorphism. Adult males have epaulettes, which are tufts of white hairs that grow within shoulder pouches (circular pocket-like folds of skin). The hairs can be held erect to form a white rosette. Adult females lack epaulettes, but they have shallow pouches that resemble those of sub-adult males.
On average, females are slightly larger than males. The average weight of males is about 20 grams, while the average weight of females is 22 grams. The forearm length ranges from 49 to 53 mm in males, and 50 to 56 mm in females.
Range mass: 24 to 34 g.
Range length: 67 to 105 mm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: female larger; sexes colored or patterned differently
There are no known predators on M. pusillus. In general, predators on bats include owls, snakes, and occasionally other bats.
Little is known about the mating behavior and system of M. pusillus.
Micropteropus pusillus is bimodally polyestrous. It has two birth periods per year, from March to May and from September to November. These periods are adjusted so that lactation coincides with the rainy season and availability of fruit. Each parturition period is followed by a post-partum estrus and then by immediate embryonic development.
Breeding occurs throughout much of the year but mostly in March, April, May, and November. The gestation period is five or six months. Weaning takes from 7 to 13 weeks.
Females are able to mate at six months, and give birth when they are eleven to twelve months old. Sub-adult males have testes less than 3 mm in length and underdeveloped epaulettes. Males reach puberty at 7 months and are fully mature by 9 months.
Growth rates for juvenile bats are the same for both sexes, although females achieve greater adult size than males. The mean growth rate for juvenile bats is about 116 milligrams per day. This slow rate is accounted for by the low protien content of their diet.
Males have enlarged vocal cords and emit a shrill ringing call. The opening and vibrating of the shoulder epaulettes in males serve to attract females. Male displays like those in the genus Epomophorous are also present.
Breeding interval: Micropteropus pusillus breeds twice a year.
Breeding season: March-May, November
Range gestation period: 5 to 6 months.
Range weaning age: 7 to 13 weeks.
Average time to independence: 9 months.
Range age at sexual or reproductive maturity (female): 6 to 12 months.
Range age at sexual or reproductive maturity (male): 7 to 9 months.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous ; post-partum estrous
Parental investment in M. pusillus is undocumented. However, young are known to roost with their mothers, implying that parental care is skewed towards the females of the species.
