The greater guinea pig (''Cavia magna'') is a

species In biology, a species is the basic unit of 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 the appropriate s ...

rodent Rodents (from Latin , 'to gnaw') are mammals of the 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 rodents. They are n ...

found in the coastal strip of

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 ...

and

Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...

, where it lives in moist grassland and marshes.

Description

A large rodent, the greater guinea pig grows to a total length of and weight of for males and a total length of and weight of for females. The dorsal fur is dark agouti brown and the underparts are reddish brown. It is semiaquatic and has membranes joining the toes. Its karyotype has 2n = 64 and FN = 128.

Distribution and habitat

This species is native to the coastal strip of land in eastern Uruguay and southeastern Brazil. Its typical habitat is moist grassland, marshes, the edges of woodland and small valleys.

Behaviour

The greater guinea pig is a herbivore. It is a solitary animal and has a complex network of tunnels and runways through the vegetation. The home range is variable and seems to be related to the animal's size, its sex, and the water level in the area. Females seem capable of breeding at any time of year but births predominate in spring and the early part of summer. Females may have up to three litters in one year. The gestation period is about 64 days and the litter size is very small (1 or 2 pups). The young are quite large when born and grow fast, and some females born in the spring themselves breed successfully when between 30 and 45 days old. This small mammal is unusual in that it produces a small number of

precocial In biology, altricial species are those in which the young are underdeveloped at the time of birth, but with the aid of their parents mature after birth. Precocial species are those in which the young are relatively mature and mobile from the mome ...

offspring with a high survival rate when it might have been expected to produce large litters of

altricial In biology, altricial species are those in which the young are underdeveloped at the time of birth, but with the aid of their parents mature after birth. Precocial species are those in which the young are relatively mature and mobile from the mome ...

young.Kraus, C. ''et al.'' 2005. Living slow and dying young? Life-history strategy and age-specific survival rates in a precocial small mammal. In: ''Journal of Animal Ecology'' 74:171–180

Status

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 nat ...

has rated the conservation status of the greater guinea pig 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. T ...

". It has a restricted range but has a total area of occupancy of more than . It is believed to have a large total population, and although the population is thought to be slightly declining in Uruguay, this is not at a rate sufficiently significant for it to be listed in a more threatened category.

References

External links

* * {{Taxonbar, from=Q1762803 Guinea pigs Mammals of Brazil Mammals of Uruguay Rodents of South America Environment of Rio Grande do Sul Mammals described in 1980