By Bridget Fahey
Geographic Range
Lasiurus ega is widely distributed from Mexico south to Argentina, but the range seems to be extending northward into parts of California, Texas, Arizona and New Mexico.
Biogeographic Regions:
nearctic 
(native ); neotropical (native ).
Habitat
Bats of the genus Lasiurus generally occur in wooded areas and roost in foliage. Occasionally these bats roost in tree holes or buildings. In the U.S. L. ega is associated with introduced palms, which is thought to be a reason for its recent expansion northward.
Terrestrial Biomes:
forest ; rainforest ; scrub forest .
Physical Description
(0.35 to 0.63 oz; avg. 0.42 oz)
A whitish buff, yellowish, or orange, usually with a blackish wash. Tail membrane is well furred.
Some key physical features:
endothermic ; bilateral symmetry .
Reproduction
Normal litter size is 2 or 3 young, although individuals have been known to have single young. Estimated gestation period is 80-90 days. Mating occurs in the late summer or fall with sperm being stored overwinter in the uterus. Ovulation and fertilization occur in the spring with births occurring from late May to early July.
Key reproductive features:
seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous ; sperm-storing .
Behavior
These bats are generally solitary, but females of some related species are known to form small nursery colonies and form flocks of several hundred for migration. Males do not generally congregate in summer, but may congregate during winter.
Key behaviors:
motile .
Food Habits
L. ega eats primarily insects caught in flight but is also known to alight on vegetation to pick off insects. Feeding flights are 6-15 m. above ground.
Economic Importance for Humans: Negative
Several cases of rabies have been reported in Lasiurus ega in southen California. In one instance, an individual landed on a human's bare foot and punctured the toe. Before 1979, there were no known instances of this species carrying rabies.
Economic Importance for Humans: Positive
May help to control harmful species of insects.
For More Information
Find Lasiurus ega information at
Contributors
Bridget Fahey (author), University of Michigan.
