The great evening bat (''Ia io'') is the largest

bat Bats are flying mammals of the order Chiroptera (). With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most birds, flying with their very long spread-out ...

in the

vesper bat 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 ...

family (Vespertilionidae) and the only living species in the genus '' Ia''. It is common to Eastern and Southeastern Asia (

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

Laos Laos, officially the Lao People's Democratic Republic (LPDR), is the only landlocked country in Southeast Asia. It is bordered by Myanmar and China to the northwest, Vietnam to the east, Cambodia to the southeast, and Thailand to the west and ...

Nepal Nepal, officially the Federal Democratic Republic of Nepal, is a landlocked country in South Asia. It is mainly situated in the Himalayas, but also includes parts of the Indo-Gangetic Plain. It borders the Tibet Autonomous Region of China Ch ...

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

and

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

), mainly living in areas with

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

cave Caves or caverns are natural voids under the Earth's Planetary surface, surface. Caves often form by the weathering of rock and often extend deep underground. Exogene caves are smaller openings that extend a relatively short distance undergrou ...

s at altitudes of . Their roost sites have been found both near the cave entrances and up to within the cave systems.

Description

The great evening bat reaches a length of . It is colored brown on the top and grayish on the bottom. Average wingspan is and it typically weighs . Not much is known about its habits and behavior. The bat usually lives in small groups. Its food consists of

insect Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...

s during the summer, as with most vesper bats. The great evening bat also sometimes feeds on small birds during the Autumn once insects become more scarce. The bat leaves its sleeping place in the late afternoon in search of food. During the winter months it may

migrate Migration, migratory, or migrate may refer to: Human migration * Human migration, physical movement by humans from one region to another ** International migration, when peoples cross state boundaries and stay in the host state for some minimum le ...

to warmer regions.

Status

The

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

lists its

conservation status The conservation status of a group of organisms (for instance, a species) indicates whether the group still exists and how likely the group is to become extinct in the near future. Many factors are taken into account when assessing conservation ...

as near-threatened. One of the threats to its survival in South Asia is human influence by

habitat destruction Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

; many caves have been turned into attractions. They have also been disturbed by farmers collecting their excrement. Also the excessive use of

insecticide Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, i ...

s poses a threat to the great evening bats.

Scientific name

At four letters, ''Ia io'' is tied with '' Yi qi'' for the shortest existing (and shortest possible) scientific name of any animal under the

International Code of Zoological Nomenclature The International Code of Zoological Nomenclature (ICZN) is a widely accepted Convention (norm), convention in zoology that rules the formal scientific name, scientific naming of organisms treated as animals. It is also informally known as the I ...

, and is one of very few scientific names composed solely of

vowels A vowel is a speech sound pronounced without any stricture in the vocal tract, forming the nucleus of a syllable. Vowels are one of the two principal classes of speech sounds, the other being the consonant. Vowels vary in quality, in loudness a ...

. The name has traditionally been associated with Io, a figure in

classical mythology Classical mythology, also known as Greco-Roman mythology or Greek and Roman mythology, is the collective body and study of myths from the ancient Greeks and ancient Romans. Mythology, along with philosophy and political thought, is one of the m ...

who was viewed as "

flighty Flighty is a flight tracking application for iOS and macOS. It includes flight tracking information, delay information, lifetime flying statistics, and a way to share your flights with friends. The app has received generally favorable reviews, ...

," and ''ia'' (ἰά), a Greek word signifying a shout or cry. However, recent interpretations by Griffiths (2022) suggest an alternative meaning behind Oldfield Thomas's choice of name. Instead of a reference to mythology, the name ''Ia io'' might be a joyful exclamation, translating to 'Shout hurrah!'. This interpretation posits that Thomas, who had recently become a Fellow of the Royal Society after three times previously being nominated but failing to receive the required endorsements, was expressing his elation through the naming of this species.

References

{{Taxonbar, from=Q132976 Vesper bats Taxa named by Oldfield Thomas Mammals described in 1902 Mammals of Nepal

Description

Status

Scientific name

See also

References