Furipterus horrensthumbless bat

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Geographic Range

Furipterus horrens occurs from Costa Rica to Peru and Brazil and onto Trinidad (UNEP-WCMC Online Database, 2001).


F. horrens is found in caves. They have also been known to live near or around streams and other moist areas deep in the forests. They have been found hanging in clusters in hollowed out logs (Nowak, 1994).

Physical Description

Length usually is from 33-40 mm, tail length around 24-36 mm, and forearm length from 30-40 mm (Nowak, 1994). Average specimens weigh about 3 grams (Nowak, 1994). The fur on the head is fairly long and thick, covering all the head as far as the mouth, almost concealing the mouth (Nowak, 1994). The tail is short, with both surfaces of the uropatagium haired (Nowak, 1994). The coloration is brownish gray, dark gray, or slaty blue above and usually somewhat lighter below (Nowak, 1994). Specimens of F. horrens (along with those of the related genus Amorphochilus) are easily distinguished by their reduced thumbs, which are included in the wing membrane that runs to the base of the small, funtionless claw (Nowak, 1994). The ears are seperate and funnel-shaped, while the snout is piglike (Nowak, 1994). Females are usually significantly larger than males. Their dental formula is 2/3, 1/1, 2/3, 3/3=36 (Nowak, 1994).

  • Average mass
    3 g
    0.11 oz


  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Average number of offspring

After being born the young position themselves head up on the mother's body (Nowak, 1994). This is in response to the unusual abdominal location of the mammae combined with the fact that the mothers hang in the usual head down position (Nowak, 1994).


F. horrens live in colonies from about 100 to 150, and sometimes upwards of 300, individuals (Nowak 1994). In these colonies they sometimes divide into separate groups of 4-30, while some colonies roost with each individuals separating from one another (Nowak 1994). They leave their caves to forage when it is dark. They use echolocation calls that are short, low intensity, and high frequency (Nowak 1994).

Communication and Perception

Food Habits

F. horrens are insectivorous. Evidence from fecal samples suggests that they mainly prey on butterflys and moths (Lepidoptera) (Nowak, 1994). They usually look for prey at heights of 1-5 meters above the forest floor (Nowak, 1994).

  • Animal Foods
  • insects

Conservation Status

F. horrens was listed as threatened, with a lower risk rating, in 1996. Currently it is not considered to be endangered or threatened (UNEP-WCMC Online Database, 2001).

Other Comments

There is no fossil record found of F. horrens (Nowak, 1994).


Matthew Haack (author), University of Michigan-Ann Arbor, Ondrej Podlaha (editor), University of Michigan-Ann Arbor.



living in the southern part of the New World. In other words, Central and South America.

World Map


young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


an animal that mainly eats meat


uses smells or other chemicals to communicate


used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.


animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.


An animal that eats mainly insects or spiders.


having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.


active during the night


rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.


reproduction that includes combining the genetic contribution of two individuals, a male and a female


associates with others of its species; forms social groups.


uses touch to communicate


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


"UNEP-WCMC Database-Animals-Furipterus horrens" (On-line). Accessed October 10, 2001 at http://www.unep-wcmc.org/index.html?http://www.unep-wcmc.org/reference/copyright.html~main.

Nowak, R. 1994. Walker's Bats of the World. Baltimore, MD: The Johns Hopkins University Press.