The cerrado mouse (''Thalpomys cerradensis'') is a

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are roden ...

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the souther ...

. It is found in the

cerrado The ''Cerrado'' (, ) is a vast ecoregion of tropical savanna in eastern Brazil, particularly in the states of Goiás, Mato Grosso do Sul, Mato Grosso, Tocantins, Minas Gerais, and the Federal District. The core areas of the Cerrado biome are ...

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

Description

The cerrado mouse has a head-and-body length of more than and is larger than the only other species in the genus, the hairy-eared cerrado mouse (''Thalpomys lasiotis''). The fur is dense and rather stiff. The general colouring resembles some members of the ''

Oligoryzomys ''Oligoryzomys'' is a genus of rodents in the tribe Oryzomyini of family Cricetidae. Many species are known as pygmy rice rats or colilargos.Musser and Carleton, 2005 The genus is found from Mexico to Tierra del Fuego and includes approximately 1 ...

'' genus. The dorsal pelage is reddish-brown, the individual hairs having blackish bases, orange central sections and blackish tips. There are also longer black guard hairs. The flanks and underparts are paler. The chin is buff and the eye-ring and cheeks orangish. The upper surfaces of the hindfeet are buff; they are small, with short outer toes and tiny claws. The tail, which is well-haired, is brown above and buff below. The

diploid number Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respecti ...

is 36.

Distribution and habitat

This mouse is restricted to the

ecoregion in Brazil, occurring in the states of

Bahia Bahia ( , , ; meaning "bay") is one of the 26 states of Brazil, located in the Northeast Region of the country. It is the fourth-largest Brazilian state by population (after São Paulo, Minas Gerais, and Rio de Janeiro) and the 5th-largest ...

Goiás Goiás () is a Brazilian state located in the Center-West region. Goiás borders the Federal District and the states of (from north clockwise) Tocantins, Bahia, Minas Gerais, Mato Grosso do Sul and Mato Grosso. The state capital is Goiânia. ...

and

Mato Grosso Mato Grosso ( – lit. "Thick Bush") is one of the states of Brazil, the third largest by area, located in the Central-West region. The state has 1.66% of the Brazilian population and is responsible for 1.9% of the Brazilian GDP. Neighborin ...

. It inhabits open grassland, savannah with occasional trees and wetter grassland areas with palms. It readily recolonises areas affected by wildfires, and is at its most numerous less than two years later.

Ecology

The cerrado mouse is most active soon after dusk and in the hours before dawn. In the state of Bahia, it is hardly ever caught in the live traps used by researchers for surveying small mammals, but its presence in the area is confirmed by its abundance in barn owl pellets (the undigested parts of their prey that the owls regurgitate).

Status

This mouse has a wide range but a rather patchy distribution. The cerrado grassland in which it lives is increasingly being threatened by the expansion of industrial-scale farming, the burning of vegetation for charcoal and the development of dams to provide irrigation. Although the population of the mouse may be in general decline, the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natur ...

has assessed its conservation status as being of

least concern A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. Th ...

because it believes the rate of population decline is not fast enough to justify placing it in a more threatened category.

References

{{Taxonbar, from=Q1764441 Thalpomys Rodents of South America Mammals of Brazil Endemic fauna of Brazil Fauna of the Cerrado Mammals described in 1990 Taxa named by Philip Hershkovitz