The hairless bat (''Cheiromeles torquatus''), also called the naked bulldog batLeong, T. M., et al. (2009)
The naked bulldog bat, ''Cheiromeles torquatus'' in Singapore—past and present records, with highlights on its unique morphology (Microchiroptera: Molossidae.
''Nature in Singapore'' 2, 215-30. and greater naked bat, is a species of

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 family Molossidae. The generic name ''Cheiromeles'' comes from the Greek word ''cheir'' (Greek for hand) and the species name is derived from the Latin ''torques'' (Latin for collar). This bat is a hawking insectivore, using echolocation to find insects on the wing. The hairless bat is mostly hairless, but does have short, bristly hairs around its neck, on its front toes, and around the throat sac, along with fine hairs on the head and tail membrane.

Habitat, distribution and range

This species is predominantly concentrated in the South East Asian regions of

Myanmar Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in northwest Southeast Asia. It is the largest country by area in Mainland Southeast Asia and has ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

Malaysia Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...

Java Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...

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 ...

Sumatra Sumatra () is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the list of islands by area, sixth-largest island in the world at 482,286.55 km2 (182,812 mi. ...

and

Borneo Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23,053,723 (2020 national censuses). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda ...

. Some are also found in the Island surrounding

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

. There is no current estimate of population size as it is highly dispersed and rarely found. It inhabits mainly lowlands, marshes, rocky surfaces with holes and crevices, dens, farms and trees. It is a colonial species, roosting in groups to conserve energy. It is typically harmless but is considered a pest in some rice growing areas.

Description

Its dark grey skin is largely hairless, but may have some fine patches of hair around the throat and under hind foot. They scent mark their territories with secretions from glands located at the tip of the neck. Sometimes these secretory glands have sub maxillary pouches located either inside the ears or beneath the neck region used for 'brooding' and 'nursing' purposes. It possesses a broad face, robust jaw, wide wings and protruding tail that is longer than the hind limb. The first toe bears a nail rather than a

claw A claw is a curved, pointed appendage found at the end of a toe or finger in most amniotes (mammals, reptiles, birds). Some invertebrates such as beetles and spiders have somewhat similar fine, hooked structures at the end of the leg or Arthro ...

, and is opposable. The dental formula is 1/1, 1/1, 1/2, 3/2 with small

incisors Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wher ...

and a

diastema A diastema (: diastemata, from Greek , 'space') is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars. More colloquially, the condition may be referred to ...

forms between upper and lower incisors.Lekagul, B., J. McNeely. 1977. Mammals of Thailand. Bangkok: Sahakarnbhat.

Reproduction

''C.torquatus'' produces an average of two litters a year and as soon as they are born, the mother leaves them at the roost to hunt. Males typically do not invest in parental care.

Behavior

They are

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

, migratory and colonial. Hunting starts early in the morning and they typically prey on larger insects than other bats.

Threats

The species' population is decreasing due to roost sites being destroyed. Additionally,

habitat fragmentation Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological proces ...

causes individuals to relocate to different regions, resulting in isolation. Some indigenous Malay people eat these bats as delicacy and kill them in large numbers. This is drastically reducing the overall population of these bats, making them vulnerable.

Conservation actions

Despite their role in pest control, their population is in danger due to human activity. Population recovery is being attempted in some regions and some are being placed in protected areas with ongoing habitat reconstruction. Attempts are also being made to educate indigenous people about their ecological importance.Nowak, R. 1991. Walker's Mammals of the World. Baltimore and London: The Johns Hopkins University Press

References

External links

Sound recordings of ''Cheiromeles torquatus'' on BioAcoustica
{{Taxonbar, from=Q1832731 Cheiromeles Bats of Southeast Asia Bats of Borneo Bats of Indonesia Bats of Malaysia Bats of the Philippines Mammals of Brunei Mammals of Myanmar Mammals of Thailand Fauna of Java Fauna of Sumatra Least concern biota of Asia Mammals described in 1824 Taxonomy articles created by Polbot