Geographic Range Pteropus dasymallus (Ryukyu flying-fox) range from the Ryukyu islands of Japan (Kuchinoerabu, Takara, Okinawa, Ishigaki, Iriomote, Hatoma, Obama, Yonakuni and some smaller islands) through parts of Taiwan (Kashoto Island, east coast Taiwan, and the Daito Islands). (Thatcher, 2004; Yoshiyuki, 1989) Biogeographic Regions

oriental native

Other Geographic Terms

island endemic

Habitat Ryukyu flying-foxes use forests for daytime roosting. Terrestrial Biomes

forest

rainforest

Physical Description Ryukyu flying-foxes are in the suborder Megachiroptera. Key characteristics of this suborder are that they have a well developed premaxillary bone, a postorbital process is present, they lack a tragus and a noseleaf, and their teeth are adapted for eating fruit. There are 5 subspecies of Ryukyu flying-foxes. They are P. d. daitoensis (Daito fruit bat), P. d. dasymallus (Erabu fruit bat), P. d. formosus (Taiwanese fruit bat), P. d. inopinatus (Orii's fruit bat), and P. d. yayeyamae (Yaeyama fruit bat). There are some character variations among the subspecies. Pteropus dasymallus daitoensis has brown wings and a yellow belly and back. The sides of the back are brown. The body is 221 mm long and forearm length 134 mm. Pteropus dasymallus dasymallus is the largest in size and darkest in color of the subspecies. The fur coloration consists of a blackish head and face, body is usually dark brown to black, and a cream colored area around neck. The forearm measured at around 137 mm. Pteropus dasymallus formosus is thought to be extinct in the wild. Pteropus dasymallus inopinatus has a brown muzzle, and it has a patch of darker fur that interrupts the white collar around its neck. Pteropus dasymallus inopinatus has an exposed lacrimal foramen. Pteropus dasymallus yayeyamae is the smallest in size among the 4 wild subspecies. The fur color varies on the dorsal and ventral sides of this subspecies. The head is usually brown and the neck a cinnamon color. (Thatcher, 2004; Yoshiyuki, 1989) Other Physical Features

endothermic

homoiothermic

bilateral symmetry Sexual Dimorphism

sexes alike Average mass 435 g 15.33 oz

Reproduction Pteropus dasymallus have low reproductive rates. In most fruit bats females don't give birth for the first time until they are one or two years old (Mickleburgh et al. 1992). One young is born at a time with a gestation period of 4 to 6 months. In P. d. daitoensis mating takes place between November and early January and birth between May and June (Thatcher 2004). (Mickleburgh, et al., 1992; Thatcher, 2004) Key Reproductive Features

seasonal breeding

gonochoric/gonochoristic/dioecious (sexes separate)

sexual

viviparous Breeding season Mating takes place between November and early January

Range number of offspring 1 (low)

Average number of offspring 1

Range gestation period 4 to 6 months

Range age at sexual or reproductive maturity (female) 1 to 2 years

Lifespan/Longevity Average lifespan

Status: captivity 24 years AnAge

Communication and Perception Communication Channels

tactile

acoustic

chemical Other Communication Modes

pheromones Perception Channels

visual

tactile

acoustic

chemical

Food Habits Pteropus dasymallus feeds almost entirely on plants and their products. Fruit makes up the bulk of the diet. Figs seem to be one of the animal's favorites. Other plant products that are eaten are the flowers and leaves. Flowers are eaten in the spring and leaves year round. Insects may also be a part of the diet of this species in the summer and autumn. One study showed that P. d. dasymallus has a more diverse diet than any other pteropodid bats ever studied. Their diet includes bark, 17 species of fruit, nine species of leaves, five species of flowers, and eight species of insects on Kuchinoerabu Island. (Thatcher, 2004; Thatcher, 2004) Primary Diet