SMOKY BATS – Furipteridae



Smoky bats are also commonly called thumbless bats. While they do have a thumb, it is small, enclosed in the edge of the wing, and can appear invisible. Other bats, on the other hand, use their thumbs to grip surfaces while crawling, and to hang right side up while giving birth. Smoky bats are among the smallest of bats, having a head and body length combined of 1.4 to 2.6 inches (3.5 to 5.8 centimeters). Their forearms are about 1.2 to 1.6 inches (3 to 4 centimeters) long. Females are slightly larger than males.

These bats appear delicate, with broad wings that are relatively long. The snout is pig-like in appearance, being short and turned up at the tip. Set close together, the nostrils are oval or triangular. Ears resemble funnel-eared bats. They are separate, large, and funnel-shaped, reaching almost to the jaw line. These bats have tiny eyes that are hidden by fur and their large ears. They also have long legs and short feet, with claws on the end of their feet. The tail is relatively long, but it does not reach past the edge of the tail membrane (layer of thin skin).

The fur is generally coarse. The smoky bat has triangular, wart-like fleshy projections around its mouth and lips.


The two species of the family are found in different areas.The thumbless bat is found west of the Andes, from central coastal Ecuador south to northern Chile. The smoky bat is found in Costa Rica, lowland Brazil, Peru and Trinidad.


Furipterids (members of the family Furipteridae) live in diverse habitats. The thumbless bat has been found living in lowland rainforests to the arid (extremely dry) deserts of South America to cultivated land. The smoky bat appears to have a narrower range of habitats, found primarily in lowland, moist forests. Many of these bats live in isolated populations. They are found primarily in caves, tree hollows, and human-made structures.


Bats in this family feed on insects, primarily moths and butterflies.


Little is known about the species of bats in this family. Because they are small, agile flyers in isolated populations, smoky bats are difficult to catch and study. It is known that these bats roost in colonies (groups) between 100 and 300 individuals.

Like all bats, the smoky bats become active at night (nocturnal). The long and broad shape of their wings allows them to fly slowly and with great agility to forage, search, for moths and butterflies. This also gives them the ability to forage for prey (animals eaten for food) in dense forest undergrowth.


People have caused the decline of the species in this family due to harming their natural habitats.


The World Conservation Union (IUCN) Red List categorizes the thumbless bat species as Vulnerable, meaning it is facing a high risk of extinction in the wild. The smoky bat is not considered threatened.