470.

Brazilian Marsh Rat

Holochilus brasiliensis

French: Oryzomys du Brésil / German: Brasilien-Sumpfratte / Spanish: Rata de marisma de Brasil

Other common names: \ Web-footed Marsh Rat

Taxonomy. Mus brasiliensis Desmarest, 1819, “ Brésil.” Restricted by P. Hershkovitz in 1955 to “Lagoda Santa [= Lagoa Santa], Minas Geraes [= Gerais],” Brazil .

This species is monotypic.

Distribution. SE & S Brazil (Minas Gerais and Espiritu Santo S to Rio Grande do Sul states).

Descriptive notes. Head-body 167-211 mm, tail 183-214 mm, hindfoot 51-56 mm; weight 130-370 g. No specific data are available for body weight. See general characters of the genus under the Venezuelan Marsh Rat ( H. venezuelae) account. Dorsum of the Brazilian Marsh Rat is cinnamon, sides are orangish, and venter is pale orange. Mystacial vibrissae are short and do not reach ear tips. Tail is unicolored and sparsely haired. Hindfeet have interdigital webbing. Skull is heavily built. Interorbital margins have moderately well-developed supraorbital crests. Incisors are opisthodont; molars are tetralophodont. Chromosomal complement is 2n = 40, FN = 56.

Habitat. Marshes, swamps, grasslands, and open wetlands, mainly associated with Atlantic Forest and Cerrado biomes.

Food and Feeding. Diet of the Brazilian Marsh Rat consists basically of leaves and other items of plant origin. Herbivorous specializations are reflected in its anatomy, such as gut morphology, lack of gall bladder, reduction or loss of mesolophid, lamination of molar cusps, and reduction in number of molar folds.

Breeding. No information.

Activity patterns. Trapping data suggests that the Brazilian Marsh Ratis nocturnal. It has more adaptations to swim than to climb and run, characterizing an amphibiouslifestyle.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. D’Elia, Hanson et al. (2015), Goncalves et al. (2015), Hershkovitz (1955), Marques (1988).