The rodent subfamily Sigmodontinae includes New World rats and mice, with at least 376 species. Many authorities include the Neotominae and Tylomyinae as part of a larger definition of Sigmodontinae. When those genera are included, the species count numbers at least 508. Their distribution includes much of the New World, but the genera are predominantly South American, such as brucies. They invaded South America from Central America as part of the Great American Interchange near the end of the Miocene, about 5 million years ago. Sigmodontines proceeded to diversify explosively in the formerly isolated continent. They inhabit many of the same ecological niches that the Murinae occupy in the Old World.
The subfamily Tylomyinae consists of several species of New World rats and mice including the vesper and climbing rats. They are not as well known as their relatives in the subfamilies Sigmodontinae and Neotominae. Many authorities place all three of these subfamilies in a single subfamily, Sigmodontinae.
The gray leaf-eared mouse is a rodent species from South America. It is found in Argentina, Bolivia, Brazil and Paraguay; its habitat includes the Gran Chaco.
Vesper mice are rodents belonging to a genus Calomys. They are widely distributed in South America. Some species are notable as the vectors of Argentinian hemorrhagic fever and Bolivian hemorrhagic fever.
Allen's big-eared bat is a species of vesper bat in the monotypic genus Idionycteris. It occurs in Mexico and in Arizona, California, Nevada, New Mexico, Utah, and Colorado in the United States.
The friendly leaf-eared mouse is a species of rodent in the family Cricetidae. It is found only in Peru.
Phyllotis is a genus of rodent in the family Cricetidae. These mice are commonly confused with Auliscomys, Graomys and Loxodontomys.. In order to tell these genera apart, one must look at the tail. Species in the genus Phyllotis have a penicillate tip on their tail which is not present in the other two genera. Tails in the genus Phyllotis are also less than the length of its head and body combined whereas in Graomys, tails are longer than the head and body combined. Phyllotis xanthopygus was found at the summit of Volcán Llullaillaco, which is the highest altitude a mammal has yet been found in nature.
The Andean leaf-eared mouse is a species of rodent in the family Cricetidae. It is found in Ecuador and Peru.
The Buenos Aires leaf-eared mouse is a species of rodent in the family Cricetidae. It is found only in Argentina.
The capricorn leaf-eared mouse is a species of rodent in the family Cricetidae. It is found in Argentina and Bolivia.
Darwin's leaf-eared mouse is a species of rodent in the family Cricetidae.
The definitive leaf-eared mouse is a species of rodent in the family Cricetidae. It is found only in west central Peru, in rocky and shrub-covered areas at elevations between 2600 and 3000 m.
The gerbil leaf-eared mouse is a species of rodent in the family Cricetidae. It is found only in Peru.
Haggard's leaf-eared mouse is a species of rodent in the family Cricetidae. It is found only in Ecuador.
The master leaf-eared mouse is a species of rodent in the family Cricetidae. It is found in Chile and Peru.
Osgood's leaf-eared mouse is a species of rodent in the family Cricetidae. It is found only in the Altiplano of northeastern Chile. The species is named after American zoologist Wilfred Hudson Osgood.
The bunchgrass leaf-eared mouse is a species of rodent in the family Cricetidae. It is found in Argentina, Bolivia, and Peru.
Wolffsohn's leaf-eared mouse is a species of rodent in the family Cricetidae. It is found only in Bolivia.
The yellow-rumped leaf-eared mouse, otherwise known as the Patagonian leaf-eared mouse, is a species of rodent in the family Cricetidae and order Rodentia. It is the most widespread member of the genus.
