Kitti's hog-nosed bat (''Craseonycteris thonglongyai''), also known as the bumblebee bat, is a

near-threatened species A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature as that may be vulnerable to endangerment in the near future, but it does not currently qualify fo ...

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 ...

and the only extant member of the family Craseonycteridae. It occurs in western

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 ...

and southeast

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 ...

, where it occupies

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

caves along rivers. Kitti's hog-nosed bat is the smallest species of bat and arguably the world's smallest mammal. It has a reddish-brown or grey coat, with a distinctive pig-like snout. Colonies range greatly in size, with an average of 100 individuals per cave. The bat feeds during short activity periods in the evening and dawn, foraging around nearby forest areas for insects. Females give birth annually to a single offspring. Although the bat's status in Myanmar is not well known, the Thai population is restricted to a single province and may be at risk of extinction. Its potential threats are primarily anthropogenic, and include habitat degradation and the disturbance of roosting sites.

Description

Kitti's hog-nosed bat is about in length and in mass, hence the common name of "

bumblebee A bumblebee (or bumble bee, bumble-bee, or humble-bee) is any of over 250 species in the genus ''Bombus'', part of Apidae, one of the bee families. This genus is the only extant group in the tribe Bombini, though a few extinct related gener ...

bat". It is the smallest species of bat and may be the world's smallest mammal, depending on how size is defined. The main competitors for the title are small

shrew Shrews (family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to different fa ...

s; in particular, the

Etruscan shrew The Etruscan shrew (''Suncus etruscus''), also known as the Etruscan pygmy shrew or the white-toothed pygmy shrew, is the smallest known extant mammal by mass, weighing only about on average. (The bumblebee bat is regarded as the smallest mammal ...

may be lighter at but is longer, measuring from its head to the base of the tail. The bat has a distinctive swollen, pig-like snout with thin, vertical nostrils. Its ears are relatively large, while its eyes are small and mostly concealed by fur.Goswami, A. 1999.
''Craseonycteris thonglongyai''
Animal Diversity Web. Retrieved on 11 April 2008. In the jaw, the premaxillae are not fused with surrounding bones, and the coronoid process is significantly reduced. Its teeth are typical of an

insectivorous A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores were ...

bat. The

dental formula Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiolo ...

is 1:1:1:3 in the upper jaw and 2:1:2:3 in the lower jaw, with large upper incisors. The bat's upperparts are reddish-brown or grey, while the underside is generally paler. The wings are relatively large and darker in colour, with long tips that allow the bat to hover. The second digit of the wing is made of a single short phalanx. And the humerus has an increased number of locking tubercles on its head and beyond. There is a considerable fusion in the axial skeleton, concerning the thoracic (three posterior vertebrae), lumbar (two posterior) and sacral (all) sections. The bat has particularly slender legs, with rather thin

fibula The fibula or calf bone is a leg bone on the lateral side of the tibia, to which it is connected above and below. It is the smaller of the two bones and, in proportion to its length, the most slender of all the long bones. Its upper extremity is ...

. Despite having two caudal

vertebra The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic ...

e, Kitti's hog-nosed bat has no visible tail. There is a large web of skin between the hind legs (the

uropatagium 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 dromaeosau ...

) which may assist in flying and catching insects, although there are no tail bones or

calcar The calcar, also known as the calcaneum, is the name given to a spur of cartilage arising from inner side of ankle and running along part of outer interfemoral membrane in bats, as well as to a similar spur on the legs of some arthropods. The cal ...

s to help control it in flight.

Range and habitat

Kitti's hog-nosed bat occupies limestone caves along rivers within dry

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, which ...

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...

forests. In Thailand, it is restricted to a small region of the

Tenasserim Hills The Tenasserim Hills or Tenasserim Range ( my, တနင်္သာရီ တောင်တန်း, ; th, ทิวเขาตะนาวศรี, , ; ms, Banjaran Tanah Seri/Banjaran Tenang Sari) is the geographical name of a r ...

in Sai Yok District, Kanchanaburi Province, within the

drainage basin A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, t ...

of the

Khwae Noi River The River Kwai (), more correctly Khwae Noi ( th, แควน้อย, , 'small tributary') or Khwae Sai Yok (, ), is a river in western Thailand. It rises to the east of the Salween in the north-south spine of the Bilauktaung range near, but ...

. While

Sai Yok National Park Sai Yok National Park ( th, อุทยานแห่งชาติไทรโยค) is a national park in Sai Yok district, Kanchanaburi Province, Thailand. The park, home to mountains, waterfalls and caves, is part of the Western Forest Co ...

in the

Dawna Hills The Dawna Range (; th, ทิวเขาถนนธงชัยตะวันตก, ทิวเขาดอยมอนกุจู), also known as Dawna Hills, is a mountain range in eastern Burma and northwestern Thailand. Its northern e ...

contains much of the bat's range, some Thai populations occur outside the park and are therefore unprotected. Since the 2001 discovery of a single individual in Myanmar, at least nine separate sites have been identified in the limestone outcrops of the Dawna and

Karen Hills The Karen Hills, () also known as Kayah-Karen Mountains, are one of the main hill ranges in eastern Burma. They are located at the SW corner of Shan State and in Kayah State, a mountainous region where the only relatively flat area is Loikaw, t ...

outside the

Thanlwin , ''Mae Nam Salawin'' ( , name_etymology = , image = Sweet_View_of_Salween_River_in_Tang_Yan_Township,_Shan_State,_Myanmar.jpg , image_size = , image_caption = Salween River in Shan State, Myanmar , map ...

, Ataran, and

Gyaing River Gyaing River
Myanmar's net is a river of

Kayin and

Mon State Mon State ( my, မွန်ပြည်နယ်, ; mnw, တွဵုရးဍုင်မန်, italics=no) is an administrative division of Myanmar. It lies between Kayin State to the east, the Andaman Sea to the west, Bago Region to the ...

s. The Thai and Myanmar populations are morphologically identical, but their echolocation calls are distinct. It is not known whether the two populations are

reproductively isolated The mechanisms of reproductive isolation are a collection of evolutionary mechanisms, behaviors and physiological processes critical for speciation. They prevent members of different species from producing offspring, or ensure that any offsprin ...

Biology

Kitti's hog-nosed bat roosts in caves in limestone hills, far from the entrance. While many caves contain only 10 to 15 individuals, the average group size is 100, with a maximum of about 500. Individuals roost high on walls or roof domes, far apart from each other. Bats also undertake seasonal migration between caves. Kitti's hog-nosed bat has a brief activity period, leaving its roost for only 30 minutes in the evening and 20 minutes at dawn. These short flights are easily interrupted by heavy rain or cold temperatures. During this period, the bat forages within fields of

cassava ''Manihot esculenta'', common name, commonly called cassava (), manioc, or yuca (among numerous regional names), is a woody shrub of the spurge family, Euphorbiaceae, native to South America. Although a perennial plant, cassava is extensively ...

and kapok or around the tops of

bamboo Bamboos are a diverse group of evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family. The origin of the word "bamboo" is uncertain, bu ...

clumps and

teak Teak (''Tectona grandis'') is a tropical hardwood tree species in the family Lamiaceae. It is a large, deciduous tree that occurs in mixed hardwood forests. ''Tectona grandis'' has small, fragrant white flowers arranged in dense clusters (panicl ...

trees, within one kilometre of the roosting site. The wings seem to be shaped for hovering flight, and the gut contents of specimens include spiders and insects that are presumably gleaned off foliage. Nevertheless, most prey is probably caught in flight. Main staples of the bat's diet include small

flies Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...

(

Chloropidae The Chloropidae are a family of flies commonly known as frit flies or grass flies. About 2000 described species are in over 160 genera distributed worldwide. These are usually very small flies, yellow or black and appearing shiny due to the virtu ...

Agromyzidae The Agromyzidae are a family commonly referred to as the leaf-miner flies, for the feeding habits of their larvae, most of which are leaf miners on various plants. A worldwide family of roughly 2,500 species, they are small, some with wing leng ...

, and

Anthomyiidae The Anthomyiidae are a large and diverse family of Muscoidea flies. Most look rather like small houseflies, but are commonly drab grey. The genus ''Anthomyia'', in contrast, is generally conspicuously patterned in black-and-white or black-and- ...

hymenoptera Hymenoptera is a large order (biology), order of insects, comprising the sawfly, sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are Par ...

ns, and

psocoptera Psocoptera are a paraphyletic group of insects that are commonly known as booklice, barklice or barkflies. The name Psocoptera has been replaced with Psocodea in recent literature, with the inclusion of the former order Phthiraptera into Psocode ...

ns. Late in the dry season (around April) of each year, females give birth to a single offspring. During feeding periods, the young either stays in the roost or remains attached to the mother at one of her two

vestigial Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on co ...

pubic nipples.

Taxonomy

Kitti's hog-nosed bat is the only extant species in the family Craseonycteridae, which is grouped in the superfamily Rhinolophoidea as a result of molecular testing. Based on this determination, the bat's closest relatives are members of the families

Hipposideridae The Hipposideridae are a family of bats commonly known as the Old World leaf-nosed bats. While it has often been seen as a subfamily, Hipposiderinae, of the family Rhinolophidae, it is now more generally classified as its own family.Simmons, 20 ...

and Rhinopomatidae. Kitti's hog-nosed bat was unknown to the world at large prior to 1974. Its common name refers to its discoverer, Thai zoologist

Kitti Thonglongya Kitti Thonglongya (, October 6, 1928 - February 12, 1974) was an eminent Thailand, Thai ornithologist and mammalogy, mammalogist. He is probably best known for two discoveries of endangered species. Life Thonglongya was born in Bangkok and gradua ...

. Thonglongya worked with a British partner, John E. Hill, in classifying bats of Thailand; after Thonglongya died suddenly in February 1974, Hill formally described the species, giving it the binomial name ''Craseonycteris thonglongyai'' in honour of his colleague.

Conservation

As of the species' most recent review in 2019, Kitti's hog-nosed bat is listed by the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

near-threatened A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature as that may be vulnerable to endangerment in the near future, but it does not currently qualify fo ...

, with a downward population trend. Soon after the bat's discovery in the 1970s, some roosting sites became disturbed as a result of tourism, scientific collection, and even the collection and sale of individuals as souvenirs. However, these pressures may not have had a significant effect on the species as a whole, since many small colonies exist in hard-to-access locations, and only a few major caves were disturbed. Another potential risk is the activity of local monks, who have occupied roost caves during periods of meditation. Currently, the most significant and long-term threat to the Thai population could be the annual burning of forest areas, which is most prevalent during the bat's breeding season. In addition, the proposed construction of a pipeline from Myanmar to Thailand may have a negative impact. Threats to the Myanmar population are not well known. In 2007, Kitti's hog-nosed bat was identified by the

Evolutionarily Distinct and Globally Endangered Evolutionarily Distinct and Globally Endangered (EDGE) species are animal species which have a high 'EDGE score', a metric combining endangered conservation status with the genetic distinctiveness of the particular taxon. Distinctive species have ...

project as one of its Top 10 "focal species".

References

External links

Information and image at ADW
{{Good article Bats by classification

Kitti's Hog-nosed Bat Kitti's hog-nosed bat (''Craseonycteris thonglongyai''), also known as the bumblebee bat, is a near-threatened species of bat and the only extant member of the family Craseonycteridae. It occurs in western Thailand Thailand ( ), histor ...

Mammals of Myanmar Mammals of Thailand EDGE species