Great evening bat

Ia io is a bat species from the family of Myotis bats ( Vespertilionidae ). You should work closely with the broad wing bats ( Eptesicus ) be related. This bat is common in many parts of East and Southeast Asia.


General features

Ia io is a great bat and reaches a head-body length of 9.0 to 10.5 centimeters; the forearm is 7.1 to 8 inches long, making it one of the largest species of bats worldwide. The fifth finger is very short and ranges up to half or two thirds of the first finger of the first finger bone. The coat color is grayish brown on the top and brown on the bottom. The face is naked, and ears covered with dense hair, they reach a length of 22-29 millimeters. The tail length is 6.1 to 8.3 inches and the tail protrudes slightly beyond the tail wing membrane addition.

Features of the skull

The skull of Ia io has a maximum length of 27 millimeters and a width in the range of the zygomatic arch from 16.7 to 17.0 millimeters. He is trained vigorously and has a well-trained sagittal crest. The basisphenoid is longer than wide, the palate is narrow.

The species has two front teeth ( incisors ), a canine ( canine ), two Vorbackenzahn ( premolar ) and three molars ( Molar ) in a maxillary half and three incisors, one canine, two Vorbackenzähne and three molars in lower jaw. Overall, the animals have 34 teeth. The outer incisor in the upper jaw is reduced with a flat crown and no central peak. The canine and the first Vorbackenzahn are close together


The bat is spread over large parts of East and Southeast Asia from southern and central China and northern India and Nepal to Myanmar, Vietnam, Laos and Thailand. In India it is found in Assam and Meghalaya, in China in the provinces of Sichuan, Guizhou, Anhui, Jiangxi, Hunan, Guangxi, Jiangsu, Yunnan, Shaanxi and Hubei.

The height distribution is 200-1700 meters.

Way of life

Not much is known about their way of life. As a place to sleep you are mainly caves. Their diet consists, as with most Myotis bats, especially of insects, where she leaves her sleeping place already in the late afternoon and goes in search of food and return early. However, as the giant noctule ( Nyctalus lasiopterus ) and the aviator Nyctalus could be demonstrated for Ia io that they captured birds regularly and feeds on it.

In the winter months it is likely to migrate to warmer regions.


Serotine bats ( Eptesicus )

Scotomanes ornatus

Ia io

Other types

Ia io in 1902 first described by Oldfield Thomas scientifically. He arranged them as a single species in the genus Ia also described by him within the Myotis bats ( Vespertilionidae ), which is monotypic until today. With Ia beaulieui Bourret, 1942 and Ia longimana Pen, in 1962, although two other species have been described, but both are considered to be synonyms of Ia io. Within the species, no further addition to the nominate subspecies are distinguished.

As a next of kin of Ia io within the Myotis bats applies also in the South Asia spread Scotomanes ornatus, which was identified in molecular biological analyzes as sister species. Sister taxon of this combined group serotine bats ( genus Eptesicus ).

The scientific term Ia io is the shortest of the International Code of Zoological Nomenclature ( ICZN ) recognized binomial species name.


The IUCN lists the species due to their large distribution area and the assumed high inventory levels as not at risk ( " least concern "). General threats to the species are not known, but locally it is affected by habitat changes. In South Asia, especially deforestation and conversion of former forest land plays a role in agricultural areas. In addition, there are often disturbances in the caves, which are used as neighborhoods.