Akodontini is the second most speciose rodent tribe of the subfamily Sigmodontinae. It includes at least 106 living species in 19 genera and is distributed mainly in the southern half of South America, with only two genera extending into Guyana (Podoxymys) and Venezuela (Necromys). It also includes genera previously placed in tribe Scapteromyini. The following genera are now generally recognized:
Bibimys is a genus of new world rats. Commonly known as the crimson-nosed rats, there are three species:
Notiomys edwardsii, also known as Edwards's long-clawed mouse, Edward's long-clawed akodont, or Milne-Edwards' long-clawed mouse, is a rodent in the tribe Abrotrichini from southern Argentina. It is the only species in the genus Notiomys, although species of Chelemys and Geoxus were formerly included in that genus.
Euryoryzomys russatus, also known as the russet oryzomys, russet rice rat, or big-headed rice rat, is a species of rodent in the family Cricetidae. It is a member of the genus Euryoryzomys, which was split off from Oryzomys in 2006. It was first described by Johann Andreas Wagner in 1848. It is found in southern Brazil, eastern Paraguay and northeastern Argentina. It is considered a large species in its genus, with a reddish-brown coat, long tail length, and large skull. It is a terrestrial rodent, spending its time foraging for seeds, fruits, and insects. It is listed by the IUCN as least concern, although studies have shown it to be influenced by anthropogenic disturbances. Predators consist of small members of the order Carnivora.
Oligoryzomys flavescens, also known as the flavescent colilargo or yellow pygmy rice rat is a species of rodent in the genus Oligoryzomys of family Cricetidae. It is found in southern South America, occurring in southern Brazil, Paraguay, Uruguay, and northeastern Argentina. Its karyotype has 2n = 64-66 and FNa = 66–70.
Holochilus brasiliensis, also known as the Brazilian marsh rat or web-footed marsh rat, is a species of semiaquatic rodent from South America. It is found in northeastern Argentina, southern and eastern Brazil and in eastern Uruguay.
The lesser Wilfred's mouse is a species of South American rodents of the family Cricetidae. It was first described by Wilfred H. Osgood under the name Thomasomys pictipes, then into the genus Wilfredomys, and now known as Juliomys pictipes. The lesser Wilfred's mouse is endemic to northeastern Argentina and southeastern Brazil. Its physical appearance ranges from dark brown to light orange coloration and the typical size is small to medium. This species is arboreal, spending most of its time trees and living in the local forests at altitudes from sea level to 2000 m. Currently, this species is listed as Least Concern by the IUCN, but, threats include livestock farming, ranching, and wood harvesting.
Lundomys molitor, also known as Lund's amphibious rat or the greater marsh rat, is a semiaquatic rat species from southeastern South America.
Abrothrix illuteus, also known as the gray akodont, gray grass mouse, or gray soft-haired mouse, is a species of small rodent in the genus Abrothrix of family Cricetidae. It is found only in northwestern Argentina.
Kemp's grass mouse is a species of South American rodent in the family Cricetidae. It is the only species in the genus Deltamys. It was formerly considered a member of the genus Akodon, but is now considered sufficiently distinct to warrant its own genus. It is named for Robin Kemp, who collected specimens of mice from the area for the British Museum.
Abrothrix longipilis, also known as the long-haired grass mouse or long-haired akodont, is a species of rodent in the family Cricetidae. It is endemic to central Argentina and Chile. Until 2014 it was thought that the species extended into southern Chile and Argentine Patagonia but these populations are now proposed to belong to closely related species named Abrothrix hirta.
Abrothrix olivacea, also known as the olive grass mouse or olive akodont, is a species of rodent in the genus Abrothrix of family Cricetidae. It is found from northern Chile into southern Chile and Argentina, including the islands of Tierra del Fuego. It is prone to large swings in population size.
Akodon spegazzinii, also known as Spegazzini's akodont or Spegazzini's grass mouse, is a rodent in the genus Akodon found in northwestern Argentina. It occurs in grassland and forest at 400 to 3,500 m above sea level. After the species was first named in 1897, several other names were given to various populations now included in A. spegazzinii. They are now all recognized as part of a single, widespread and variable species. Akodon spegazzinii is related to Akodon boliviensis and other members of the A. boliviensis species group. It reproduces year-round. Because it is widely distributed and common, Akodon spegazzinii is listed as "least concern" on the IUCN Red List.
The Colombian forest mouse is a species of rodent in the family Cricetidae. Some authorities consider it to be the only species in the genus Chilomys, while others accept Chilomys fumeus as being a valid species, and it may form part of a species complex. It is found in Colombia, Ecuador, and Venezuela.
The Patagonian chinchilla mouse is a species of rodent in the family Cricetidae. It was first described by George Robert Waterhouse in 1839. It is found in Tierra del Fuego and neighboring areas of southernmost Argentina and Chile.
Holochilus chacarius, also known as the Chacoan marsh rat or Chaco marsh rat, is a semiaquatic rodent species in the family Cricetidae. It is found in Argentina and Paraguay within the Gran Chaco.
Irenomys tarsalis, also known as the Chilean climbing mouse, Chilean tree mouse, or long-footed irenomys, is a rodent found in Chile, from about 36° to 46°S, and in adjacent Argentina, mainly in forests. It is a large, long-tailed, soft-furred mouse characterized by grooved upper incisors and specialized molars with transverse ridges, divided by deep valleys, which are connected by a transverse ridge along the midline of the molars.
Oligoryzomys longicaudatus, also known as the long-tailed colilargo or long-tailed pygmy rice rat, is a species of rodent in the genus Oligoryzomys of the family Cricetidae. It is found in the southern Andes of Chile and Argentina, with an outlying population in eastern Argentina. As a common species with a wide range and a stable population, the International Union for Conservation of Nature has rated this rodent as being of "least concern".
Oligoryzomys magellanicus, also known as the Patagonian colilargo and the Magellanic pygmy rice rat, is a species of rodent in the genus Oligoryzomys of the family Cricetidae. It is found in the southernmost parts of Argentina and Chile, including Tierra del Fuego and other outlying islands. Its karyotype has 2n = 54 and FNa = 66.
Abrotrichini, also known as the Andean clade or southern Andean clade, is a tribe of rodents in the subfamily Sigmodontinae. It includes about fifteen species in four genera, distributed in South America from southern Peru to southernmost South America, including the Patagonian steppes. The earliest known fossils are from the Pliocene of Argentina.
