By LeeAnn Bies
Geographic Range
Metachirus nudicaudatus, brown four eyed opossums, range from Nicaragua to Paraguay and N. Argentina (Redford and Eisenburg, 1992).
Biogeographic Regions:
neotropical
(native
).
Habitat
(2296 ft)
Brown four eyed opossums are both arboreal and terrestrial, but more often are found on the ground. They inhabit lowlands, heavy forests, or open brush country. They build round nests in tree branches or at times under rocks and logs (Hunsaker, 1977). The nests are made of leaves and twigs (Nowak, 1997).
These animals are found in the following types of habitat:
tropical
.
Terrestrial Biomes:
forest
; scrub forest
.
Physical Description
(28.16 oz)
(1.87 to 2.07 ft)
In general, M. nudicaudatus is grayish-brown in color. The back and sides are darker brown. The head has a dark band stretching from the tip of the snout over the eyes and across the base of the ear, making the face look almost black. In some individuals, this band extends past the ears. The eyes are large, rounded, and completely dark. A creamy white spot over each eye gives the animals their "four-eyed" name. The fur is short, thick, and silky. The venter (belly or abdomen) is usually white or cream. The tail is furred partially near the base. The rest of the tail, the scaly part, is multicolored--part black and part white. The length of the tail is usually around 330 mm, being longer than the body which is about 265 mm (Nowak, 1997; Redford and Eisenburg, 1992). The females are 71% lighter than the males (Hansen et al., 1999).
Some key physical features:
endothermic
; bilateral symmetry
.
Reproduction
seasonally polyestorus, November (Central America)
Brown four eyed opossums are seasonally polyestrous, meaning that they are capable of breeding many times through out the year. In Central America, though, they are reported to breed in November. The female of this species does not have a pouch like most marsupials. Instead lateral folds of skin exist on the lower abdomen, on which the mammae are located (females with 5, 7, and 9 have all been recorded). Therefore, the young does not crawl into the pouch after birth like other marsupials. A 51-mm young was reported to be capable of standing on its own. It rode on its mother's hips or back and was fully independent 2 months later (Nowak, 1997).
Key reproductive features:
gonochoric/gonochoristic/dioecious (sexes separate); sexual
; fertilization
(internal
); viviparous
.
Lifespan/Longevity
The maximum lifespan of M. nadicaudatus is three to four years (Nowak, 1997)
Behavior
Brown four eyed opossums are completely nocturnal, hardly moving from their nests until dark. In a capture-mark-recapture study over two years, M. nudicaudatus was found to be highly mobile and exploratory. It also had a short residence time. It has been observed that when M. nudicaudatus is held in the hand it hardly makes any noise (Nowak, 1997; Gentile and Cerquiera, 1995).
Food Habits
This species is mainly frugivorous. However, their diet can also include insects, bird's eggs, small vertebrates such as reptiles, and also small invertebrates (Hunsaker, 1977). In a study which examined the feces of individuals, some brown four eyed opossums were found to consume more ants, termites, cockroaches and beetles than any other food in their diet (Freitas et al., 1997).
Animal Foods:
amphibians; eggs; insects.
Plant Foods:
fruit.
Ecosystem Roles
As an insectivore, M. nudicaudatus clearly helps to keep the numbers of insects in its habitat under control (Freitas et al., 1997).
Key ways these animals impact their ecosystem:
disperses seeds.
Economic Importance for Humans: Negative
This species has been accused of destroying fruit crops in certain areas (Nowak, 1997).
Ways that these animals might be a problem for humans:
crop pest.
Economic Importance for Humans: Positive
Brown four eyed opossums consume pests such as ants, termites, and cockroaches (Frietas et al., 1997).
Ways that people benefit from these animals:
controls pest population.
Conservation Status
IUCN Red List: [link]:
Lower Risk - Least Concern.
US Federal List: [link]:
No special status.
CITES: [link]:
No special status.
We have no text on this topic for this species. Look to the sidebar on the right for some limited information.
Contributors
LeeAnn Bies (author), University of Michigan.
Kate Teeter (editor), University of Michigan.

