The hairless bat (''Cheiromeles torquatus''), also called the naked bulldog bat
[Leong, 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 mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". 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 bi ...
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, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John C. Wells, Joh ...
,
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...
,
Malaysia
Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...
,
Java
Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's List ...
,
Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...
,
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 sixth-largest island in the world at 473,481 km2 (182,812 mi.2), not including adjacent i ...
and
Borneo
Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...
. Some are also found in the Island surrounding
Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no),
* bik, Republika kan Filipinas
* ceb, Republika sa Pilipinas
* cbk, República de Filipinas
* hil, Republ ...
. 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 tarsus ...
, 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, wh ...
and a
diastema
A diastema (plural diastemata, from Greek διάστημα, 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 ...
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 an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
, migratory and
colonial
Colonial or The Colonial may refer to:
* Colonial, of, relating to, or characteristic of a colony or colony (biology)
Architecture
* American colonial architecture
* French Colonial
* Spanish Colonial architecture
Automobiles
* Colonial (1920 au ...
. 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 processes ...
causes individuals to relocate to different regions, resulting in isolation. Some indigenous
Malay
Malay may refer to:
Languages
* Malay language or Bahasa Melayu, a major Austronesian language spoken in Indonesia, Malaysia, Brunei and Singapore
** History of the Malay language, the Malay language from the 4th to the 14th century
** Indonesi ...
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 Indonesia
Bats of Malaysia
Mammals of Borneo
Mammals of Brunei
Mammals of Myanmar
Mammals of Thailand
Mammals of the Philippines
Fauna of Java
Fauna of Sumatra
Least concern biota of Asia
Mammals described in 1824
Taxonomy articles created by Polbot