Description:
Lutreolina crassicaudata is similar in size to Philander opossum (Marshall 1978) without the facial markings. The fur is variable in color from reddish-yellow to dark brown. It has short, rounded ears that barely protrude above its fur. The head and body length is 210-445 mm. (Nowak 1994), with it tail being 210-310 mm. The tail is also somewhat prehensile and the last 50 mm from the tip is naked (Redford and Eisenberg
1992). L. crassicaudata weighs between 200 and 450 grams.
There is also evidence of sexual dimorphism in that males are usually larger than the females. L. crassicaudata are members of the Marsupial family, therefore have a pouch. The pouch may be undeveloped (Marshall 1978), but records have shown up to seven young inside a single pouch (Lemke 1982).
Distribution:
There are two major populations in South America. The larger area of the two is east of the Andes to Uruguay, Paraguay, northern Argentina, and southern Brazil. The other population inhabits Columbia, Venezuela, and Guyana. The lutrine opossum lives in grassland, savanna, and some woodland environments near permanent water. They have also been trapped up to 1700 m in elevation (Redford and Eisenberg 1992).
Ontogeny and Reproduction:
L. crassicaudata is a very secretive animal, therefore not much is known of its reproduction. However, it is believed that this animal breeds in the spring and again later in the year when their young are old enough to be on their own. The gestation period is believed to be about 14 days (Mares et al. ).
Ecology and Behavior:
L. crassicaudata is a nocturnal animal, as well as a good swimmer and climber.
The live in nests of grass, in holes in trees, or in abandoned burrows of armadillos and viscachas (Lemke 1982). The home range has been estimated to be about 800 m
2 . It’s a very vocal for a marsupial and communicates with a long, high-pitched whistle (Nowak
1994).
The lutrine opossum has an omnivorous diet and has been referred as seasonally opportunistic (Caceres 2002). When hunting, it kills its prey with a quick bite to its neck
(Lemke et al. 1982). It feeds on small mammals, birds, reptiles, fishes, and insects
(Marshall 1978). It has also been recorded to eat fruit, mollusks, crabs, beetles, and seeds
(Caceres 2002). It also has a habit of washing its face once it gets done eating (Nowak
1994).
Remarks:
There were once up to five different subspecies. There are currently two subspecies recognized, L.c. crassicaudata and L.c. turneri . The others were categorized

into these two. The lutrine opossum is called “comadreja,” which means “weasel,” by
Spanish-speaking natives (Marshall 1978).
Literature Cited:
Caceres, N., I. Ghizoni Jr, M. Graipel. 2002. “Diet of two marsupials, Lutreolina
crassicaudata and Micoureus demerarae, in a coastal Atlantic Forest island of
Brazil”. Mammalia , 66(3): 331-40.
Lemke, T., A. Cadena, R. Pine, J. Hernandez-Camacho. 1982. “Notes on opossums, bats,
and rodents new to the fauna of Columbia”. Mammalia , 46(2): 225-34.
Marshall, L.G. 1978. Mammalian Species , 91: 1-4.
Mares, M.A., R.A. Ojeda, and R.M. Barquez. Guide to Mammals in Salta Province in
Argentina
Nowak, R.M. 1994.
Walker’s Mammals of the World.
Vol. 1. 6 ed. 34-5.
Redford, K.H. and J.F. Eisenberg. 1992. Mammals of the Neotropics: The Southern
Cone. Vol.2, 22-3.
Reference written by Adam Sinkula, Biology 378 (Mammalogy), University of Wisconsin
– Stevens Point. Edited by Christopher Yahnke. Page last updated August 8, 2005.