113.

Tricolored Big-eared Bat

Glyphonycteris sylvestris

French: Glyphonyctere sylvestre / German: Dreifarbige GroRohrblattnase / Spanish: Glifonicterio silvestre

Other common names: Brown Small-eared Bat, Little Graybeard Bat, Tricolored Bat

Taxonomy. Glyphonycteris sylvestris Thomas, 1896,

“Imravalles [= Hacienda Miravalles, Guanacaste], Costa Rica.”

Glyphonycteris sylvestris was included in Micronycteris. Monotypic.

Distribution. Patchily distributed from C Mexico (Nayarit and Veracruz) through Central America (Honduras, Nicaragua, Costa Rica, and Panama) into South America, including Colombia, Venezuela, the Guianas, Brazil, E Ecuador, and E Peru; also on Trinidad 1.

Descriptive notes. Head-body 48-56 mm, tail 9-12 mm, ear 17-22 mm, hindfoot 11-12 mm, forearm 38-44 mm; weight 7-11 g. The Tricolored Big-eared Bat is similar to Davies’s Big-eared Bat (G. davies) but smaller. Dorsal hair is tricolored. Ears are large, wide, and pointed. Dental formula is12/2, C1/1,P 2/3 M 3/3 (x2) = 34.

Habitat. Primary and little-disturbed humid tropical and subtropical forests at elevations of 15-1300 m. The Tricolored Big-eared Bat inhabits terra firma and seasonally inundated forest.

Food and Feeding. The Tricolored Big-eared Bat is a gleaning insectivore and apparently eats some fruits.

Breeding. Reproductive period of the Tricolored Big-eared Bat apparently begins in rainy seasons. In Mexico, none of 13 specimens captured in December were sexually active; females were not pregnant, and testes of the males were small.

Activity patterns. The Tricolored Big-eared Bat is nocturnal. It roosts in caves, tunnels, and hollow trees.

Movements, Home range and Social organization. The Tricolored Big-eared Bat forms colonies. In Trinidad Island, a colony of 75 individuals was found, sharing space with the Greater Sac-Winged Bat (Saccopteyx bilineata). In Mexico, a colony of 25 individuals was found in a cave, and in another cave, a single individual was found together with four Gray Sac-winged Bats (Balantiopteryx plicata).

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Tricolored Big-eared Batis rare, patchily distributed, and poorly known. Apparently, its conservation status is stable in most of its distribution.

Bibliography. Felix et al. (2016), Goodwin & Greenhall (1961), Hall & Dalguest (1963), Linares (1987), Medina-Fitoria & Saldana (2012), Morales-Martinez & Suérez-Castro (2014), Simmons (1996), Tirira (2017), Tirira et al. (2016), Williams & Genoways (2008).