Idionycteris phyllotis is a bat with large ears, weighing 8 to 16 grams. On the dorsal side they possess long and soft pelage,[3] (fur). Their fur is basally blackish in color with tips that are a yellow-gray color. They have a black patch on each shoulder, a tuft of white hair on the backside of the ears, as well as ventral hairs that are black with pale tips.[3] The calcar possesses a low keel. The uropatagium has 12 to 13 transverse ribs. The rostrum is flattened and broad.[3] They have distinctive lappets (disc-shaped protrusions), which project from the base of the ears onto the brow of the bat.[4]
I. phyllotis has an external morphology common to that of gleaning bats, and are thus well adapted for plucking stationary insects from surfaces.[3] To do this they have long tragi and ears, wings adapted for maneuverability and hovering flight, and a gracile jaw.[3]I. phyllotis) is the only species in North America known to emit long, constant frequency-frequency modulated echolocation calls.[2]
Allen’s big-eared bat inhabits the southwestern mountainous regions of Mexico and the United States. This species occupies a wide range in elevation, ranging from 855 m to 3,225 m, though most specimens reside at altitudes between 1,100 m and 2,500 m.[3]
^ abHayes, Mark A.; Navo, Kirk W.; Bonewell, Lea R.; Mosch, Cyndi J.; Adams, Rick A. (2009). "Allen's big-eared bat (Idionycteris phyllotis) documented in Colorado based on recordings of its distinctive echolocation call". The Southwestern Naturalist. 54 (4): 499–501. doi:10.1894/JKF-01.1.
