Smithsonian National Museum of Natural History, North American Mammals
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  Chiroptera · Vespertilionidae · Lasiurus xanthinus
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Lasiurus xanthinus

Western Yellow Bat

Order: Chiroptera
Family: Vespertilionidae


Conservation Status: Least Concern.

Western Yellow Bats have small bodies, short, broad muzzles, and long narrow wings - as do their close cousins, Southern Yellow Bats. In fact, many scientists thought Lasiurus xanthinus was a subspecies of Lasiurus ega, but recent work suggests that they have evolved into two distinct species. Western Yellow Bats occur in southern California, Arizona, New Mexico, Baja California, and western and central Mexico, but have not been found farther south than Mexico. Southern Yellow Bats are found in southern Texas, eastern and southern Mexico, and on down into South America. Both species have soft, silky fur that extends onto their wings and as far as halfway onto the tail membrane.

These bats are found in various kinds of habitats. They often roost in trees, usually with only one bat occupying a tree. They leave the roost to hunt at sunset and are active until midnight or even longer before returning. There is no evidence that they store fat or hibernate. Known predators include cats, dogs, and barn owls.

Average: Total Length: 115.1 mm
Range: Total Length: 102-118 mm

Average: 11.9 g
Range: 10-14 g


Thomas, O., 1897. Annals and Magazine of Natural History, ser. 6, 20:544.


Mammal Species of the World

Distribution of Lasiurus xanthinus