Pig nosed bat
| Pig nosed bat | ||||||||||||
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Stuffed specimen in the Japanese National Museum of Natural Sciences |
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| Systematics | ||||||||||||
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| Scientific name of the family | ||||||||||||
| Craseonycteridae | ||||||||||||
| Hill , 1974 | ||||||||||||
| Scientific name of the genus | ||||||||||||
| Craseonycteris | ||||||||||||
| Hill, 1974 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Craseonycteris thonglongyai | ||||||||||||
| Hill, 1974 |
The pig- nosed bat or bumblebee bat ( Craseonycteris thonglongyai ) is a species of bat . It is classified in its own family, Craseonycteridae, and is considered the smallest species of bat and, together with the Etruscan shrew, the smallest species of mammal .
features
These animals reach a head trunk length of 29 to 33 millimeters and a weight of 1.7 to 2 grams. Their wingspan is 13 to 15 centimeters with a forearm length of 22 to 26 mm. Their fur is colored red-brown or gray on the upper side, the underside is lighter and the wings are colored black. With the exception of two remaining vertebrae, these bats have no tail and no calcar (a thorn on the ankle that is used in other bats to stretch the tail membrane). The wings are long and dark in color, the uropatagium (the flight membrane between the legs) is relatively large.
The head is small (around 11 millimeters long) and characterized by the pig-like , protruding snout with a thickened plate in the area of the forward nostrils. The ears are large and pointed and, when presented, reach above the tip of the nose; they don't meet at the grassroots. The tragus is medium in size, narrow and rounded at the tip. The eyes are small and partially covered by fur. Males are also characterized by a conspicuous gland on the throat.
distribution
The pig - nosed bat was originally found exclusively in the valley of the Kwae Noi River (River Kwai) in the western Thai province of Kanchanaburi , Sai Yok National Park .
It is restricted to limestone caves near the river as a place to sleep and usually only flies 1 km from there. The height distribution ranges from 0 to 500 meters. There are 35 known caves in Thailand and 8 caves in nearby Myanmar to the south , in which pig-nosed bats have been identified.
It was not discovered until the 1970s (see below); Limestone mining as fertilizer, tourism and the ritual burning of incense sticks in the caves have reduced their population to a few thousand today. The species was added to the EDGE list of threatened and evolutionarily important species. One - found dead - specimen from the Natural History Museum Vienna was in the exhibition The Business with Death - the last extinction of species? to see.
Way of life
Pig-nosed bats are sociable and use the limestone caves as sleeping places. They spend the day and the deep night in a torpor-like sleep in larger groups inside the caves, with a relatively large amount of space between the individual animals. During dusk and dawn they go in search of food and leave the caves to do so.
nutrition
These bats feed exclusively on very small insects and spiders, which they find by means of echolocation during flight and which they peck from the plants. Two- winged birds (Diptera) make up about 80% of the prey; there are also hymenoptera (Hymenoptera) and dust lice (Psocoptera). The hunting flight takes place in the forest area, mainly in the trees and bamboo areas.
Reproduction
Little is known about the reproduction of these animals. The mating season is in April, at the beginning of the dry season, and as with all bats, a single young is usually born.
Systematics
Pig nosed bats were not discovered until 1973. The Thai researcher Kitti Thonglongya initially thought the animals were an unknown type of beetle - or bumblebee - before he got a closer look at them. He then turned to the English researcher John Edwards Hill . Thonglongya died suddenly in 1974, so Hill described the species and recognized it as a new genus, even a new family. The name of the Thai explorer lives on in the species name thonglongyai .
The closest relatives of the pig nosed bat are the large-leaf noses (Megadermatidae).
Hazard and protection
The total population of the pig nosed bat lives in eight known caves in Myanmar and 35 caves in Thailand. In Thailand, the population was estimated at 5,100 animals in 2008 and is declining. It is estimated that stocks decreased by 10% between 1983 and 1997 and by around 14% between 1998 and 2008. A population of 1,500 animals has been estimated for Myanmar. According to these estimates, fewer than 10,000 specimens live in the distribution area with a continuing decline in the population, which is assumed to be a further 10% for the next 10 years.
These animals are therefore endangered species . Parts of their already small distribution area have fallen victim to the clearing. In addition, souvenir hunters and researchers are repeatedly drawn to the reputation of being the 'smallest mammal' and they catch animals. The International Union for Conservation of Nature and Natural Resources (IUCN) lists the bat as an endangered species ("vulnerable").
supporting documents
- ↑ a b c J. E. Hill, Susan E. Smith: Craseonycteris thonglongyai . In: Mammalian Species . tape 160 , 1981, pp. 1–4 ( full text (PDF; 560 kB)).
- ↑ a b c d e f g Anjali Goswamy: Craseonycteris thonglongyai in the Animal Diversity Web of the University of Michigan Museum of Zoology. Retrieved January 8, 2012.
- ↑ a b c d Craseonycteris thonglongyai in the endangered Red List species the IUCN 2011. Posted by: P. Bates, S. Bumrungsri, C. Francis, 2008. Accessed 13 January 2012 and 25 February, 2014.
- ↑ http://wien.orf.at/news/stories/2632870/ NHM shows the world's smallest mammal, ORF.at from February 24, 2014.
- ^ Teeling, EC; Springer, M .; Madsen, O .; Bates, P .; O'Brien, S .; Murphy, W. (2005). A Molecular Phylogeny for Bats Illuminates Biogeography and the Fossil Record . Science. 307 (5709): 580-584. doi: 10.1126 / science.1105113
literature
- JE Hill, Susan E. Smith: Craseonycteris thonglongyai . In: Mammalian Species . tape 160 , 1981, pp. 1–4 ( full text (PDF; 560 kB)).
Web links
- Craseonycteris thonglongyai in the endangered Red List species the IUCN 2011. Posted by: P. Bates, S. Bumrungsri, C. Francis, 2008. Accessed January 13, 2012 Design.
- Species portrait of the pig nosed bat on the pages of Evolutionarily Distinct and Globally Endangered (EDGE).
- Anjali Goswamy: Craseonycteris thonglongyai in the Animal Diversity Web of the University of Michigan Museum of Zoology. Retrieved January 8, 2012.
- Wilfried Stevens: The Thai bumblebee bat. onlinezeitung24.de, February 7, 2015