The Japanese short-tailed bat (''Eptesicus japonensis'') is a species of bat belonging to the family

Vespertilionidae Vespertilionidae is a family of microbats, of the order Chiroptera, flying, insect-eating mammals variously described as the common, vesper, or simple nosed bats. The vespertilionid family is the most diverse and widely distributed of bat famili ...

. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

to Japan where it is found at the base of the northern

Japanese Alps The is a series of mountain ranges in Japan which bisect the main island of Honshu. The peaks that tower over central Honshu have long been the object of veneration and pilgrimage. These mountains had long been exploited by local people for raw m ...

, the

Chichibu is a city located in Saitama Prefecture, Japan. , the city had an estimated population of 61,159 in 26,380 households and a population density of . The total area of the city is . Geography Chichibu is in the westernmost part of Saitama. Unl ...

Mountains and

Oze National Park , is an area consisting of open greenland in Fukushima, Tochigi, Gunma and Niigata Prefectures in Japan. The park is 372 km² in area and is the 29th national park in Japan. Opened on 30 August 2007, the park's area includes the marshes ...

, mostly at altitudes higher than 700 m.

Description

The Japanese short-tailed bat is small with a head and body length of 58 to 68 mm. Forearm length is 38 to 41.5 mm, tail length is 35 to 43 mm, foot length is 8.7 to 11.5 mm, and ear length is 13 to 16.5 mm. Its fur is short, soft and shiny, with dark blackish-brown dorsal parts, yellowish-brown ventral parts, and a golden brown collar that extends from behind the ears to the chest. The nostrils are prominent and the muzzle is wide due to the presence of two glandular masses on the sides. The wing membranes are broad, thick, opaque and attached to the rear base of the

metatarsal The metatarsal bones, or metatarsus, are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, the metatarsal bones are numbered from the med ...

bone of the big toe. The tip of the tail extends slightly beyond the

interfemoral membrane The patagium (plural: patagia) is a membranous body part that assists an animal in obtaining lift when gliding or flight. The structure is found in extant and extinct groups of flying and gliding animals including bats, birds, some dromaeosaurs, ...

that connects the legs.

Population and distribution

There is limited information about this species. Only a few surveys have been carried out, with about 20 records reported. They are thought to be rare with patchy distribution across Japan. Individuals have been observed above 700 m around the northern Japanese Alps, the mountains near Chichibu and in Oze National Park. It roosts in hollow trees.

Conservation status

The species is listed as vulnerable by the IUCN because it has so far only been observed in an area of less than 5,000 km². It is also facing problems with damage and destruction of its habitat. The bats normally roost in hollow trees, deforestation leads to a loss of these roost sites and they then roost in buildings where they are vulnerable to disturbances by human activity.

References

External links

{{Taxonbar, from=Q3267343 Mammals described in 1953 Eptesicus Endemic fauna of Japan Mammals of Japan