172.

Transparent-winged Big-eared Brown Bat

Histiotus diaphanopterus

French: Sérotine diaphane / German: Glasflligel-Grof 3ohrfledermaus / Spanish: Histiotus de alas transparentes

Taxonomy. Histiotus diaphanopterus Feijo, Rocha & Althoff, 2015,

“Boqueirao da Onca (09°52'48.9" S, 41°4'15.2" W), in the village of Sao Pedro do Lago, located in the municipality of Sento Sé, state of Bahia, Brazil.”

This species is monotypic.

Distribution. Known from scattered localities in NE & CW Brazil and C Bolivia.

Descriptive notes. Head-body 52-60-2 mm, tail 43-57 mm, car 28.-8-33-1 mm, hindfoot 7-9-10-9 mm, forearm 41-8-49 mm; weight 8-11 g. Dorsal hairs of the Transparent-winged Big-eared Brown Bat are strongly bicolored, with dark brownish bases and brownish-golden or yellow tips; ventral hairs have strongly contrasting dark brown bases and white tips. Ears are translucent, very well developed, triangular, and connected by well-developed membrane (c. 4 mm high) across forehead; bases of ears have slightly yellowish hairs; and tragus is triangular and broad, reaching almost one-half the ear length. Face is pale and mostly naked. Membranes are naked, transparent, and pale. Calcar is well developed, with small keel. Braincase is wide; rostrum slopesslightly upward to braincase; sagittal crest is poorly developed; basisphenoid pits are absent; zygomatic arches have well developed, triangular postorbital processes in medial part ofjugal; and auditory bullae are well developed. I* is spatulated; I° is diminutive and triangular; upper incisors are separated from canines by small gap; P* is well developed; lower incisors are tricuspid; P, is small, about one-third the length of P,; upper and lower molars are W-shaped; and M” is reduced.

Habitat. Bolivian Chaco, Brazilian Caatinga, and Brazilian Cerrado in grasslands, savannas, open woodlands, and xeric thorn forests at elevations of 640-1800 m. Transparent-winged Big-eared Brown Bats were captured in understory over a seasonal watercourse in a region ofhills and valleys more humid than surroundings.

Food and Feeding. No information.

Breeding. In Mato Grosso, central Brazil, a lactating Transparent-winged Big-eared Brown Bat was captured in October.

Activity patterns. Transparent-winged Big-eared Brown Bats were found roosting in a church and abandoned house. Echolocation calls present FM components. Pulses have mean start frequency of 37-3 kHz, mean end frequency of 15-3 kHz, mean duration of 2-8 milliseconds, mean interpulse interval of 113-7 milliseconds, and mean frequency of maximum energy of 28-3 kHz.

Movements, Home range and Social organization. No information.

Status and Conservation. Not assessed on The IUCN Red List.

Bibliography. Arias-Aguilar et al. (2018), Bianconi & Pedro (2017), Feij6, Rocha & Althoff (2015), Semedo & Feij6 (2017).