Furipterus horrens
thumbless bat

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).

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).

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).

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).

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).

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