Perception Channels: tactile ; chemical
Currently Philander opossum is not thought to be threatend.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Philander opossum has been known to feed upon corn fields and fruit crops, damaging farmers fields. (Nowak 1997)
Philander opossum helps control the populations of insects and other small vertebrates. (Fonseca SD)
Philander opossum is omnivorous. About half of its diet consists of small animals such as insects, earthworms, birds, lizards, eggs, frogs, and small mammals. The remainder of the diet includes leaves, seeds, and fruits such as papayas and bananas. (Fleck 1995, Julien-Laferriere 1990, Nowak 1997, Fonseca 1991)
Philander opossum has a range that extends from Northeastern Mexico to Southeatern Brazil. Within this range, P. opossom may be found from Brazil's Atlantic coast westward into Peru and Argentenia, as well as throughout Central America. (Nowak 1997, Fonseca 1991, Cerqueira 1993)
Biogeographic Regions: neotropical (Native )
Philander opossum is found mainly in tropical forested areas, however, they may be found in the southern portions of South America in which the habitat is more temperate. In general, P. opossum resides in areas that receive greater than 1000 mm of rain per year.
Due to its proficient swimming ability, P. opossum may be found on islands. (Fonseca 1991, Adler 1996)
Terrestrial Biomes: forest ; rainforest ; scrub forest
Average lifespan
Status: captivity: 2.3 years.
The common name is derived from this opossum's grey coat and the single white spots which are located directly above each eye, providing it with an appearance of four eyes.
The body length is 250-350 mm, and the tail reaches to about the same length. Males may be slightly larger than females, although much overlap in size is present. Females have five to nine mammae contained within a pouch.
The coloration of the short, straight hair is gray dorsally and off-white to yellow ventrally. The tail is furred with the same gray coloration for 50-60 mm from the base. The tip of the tail is naked and becomes paler in color towards its end.
The ears are naked as well.
Philander opossum has a slender body and a large head. Its rostrum is fairly long and narrows at the tip. The tail tapers as well, and it is prehensile. The hind limbs are longer and more muscular than the forelimbs. (Vieira 1997, Nowak 1997, Julien-Laferriere 1990)
Range mass: 220 to 680 g.
Other Physical Features: endothermic ; bilateral symmetry
Average basal metabolic rate: 1.886 W.
Most populations of this species reproduce seasonally. During the rainy seasons, fruit is plentiful and more young may be cared for, while during the dry seasons, fruit is rare and few young are born. However, Philander opossum does reproduce throughout the year, but at lower levels during the months of June to August. Reproduction only ceases entirely when the mother's nutritional requirements are not met.
Although reproduction occurs year round, success is low. Death of young within the mother's pouch is common, especially during the dry months.
The young nurse in the mother's pouch, as that is where the nipples are located. Lactation lasts approximately 90 days, with much growth occurring after the weaning period. Following weaning, young P. opossum increase their body mass by a factor of ten.
Litter sizes vary from 1 to 7 young with the average litter containing 4 or 5 young. Larger females, those over 445 grams, tend to have larger litters (about 5 per birth), while smaller females, those under 445 grams, have fewer young per birth (about 3.8).
Females become sexually mature at about 6 to 8 months. At this time they weigh over 200 grams. Life expectancy is one to two years. (Julien-Laferriere 1990, Fleck 1995, D'Andrea 1994, Nowak 1997, Adler 1996)
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
Average birth mass: 0.2 g.
Average number of offspring: 5.
Average age at sexual or reproductive maturity (female)
Sex: female: 450 days.
The gray four-eyed opossum (Philander opossum) is an opossum species from Central and South America, ranging from southern Mexico to Peru, Bolivia and southwestern Brazil, at altitudes from sea level to 1600 m,[2] but generally below 1,000 metres (3,300 ft).[3] Its habitats include primary, secondary and disturbed forest.[2] It is one of many opossum species in the order Didelphimorphia and the family Didelphidae.
It has a sharply defined white spot above each eye, hence the common name.[4][5] Its prehensile tail is bicolored, with a pale distal part and a longer proximal darker gray part, and is naked at the end. Its dorsal fur is gray, while its ventral fur, throat, and cheeks are cream-colored. Adults have ears that are black except at the base.[3] Wild specimens weigh 200–674 grams (7.1–23.8 oz), while captive specimens can weigh up to 1.5 kilograms (3.3 lb).[5] Body length ranges from 22.0 to 33.1 centimetres (8.7 to 13.0 in) with a tail in a similar size range, 19.5 to 35.5 centimetres (7.7 to 14.0 in).[5]
The species is nocturnal, solitary and partly arboreal.[2] It is usually found in moist areas, often near streams, although it wanders in many different vegetation types.[2] It is a good swimmer.[2]
Gray four-eyed opossums do not have a well defined territory, and home range stability depends on the availability of adequate resources.[4] They are omnivorous, feeding on small animals and vegetation, such as leaves, seeds, and fruits.[5]
The gray four-eyed opossum does not "play dead" like the North American Virginia opossum. Instead it is aggressive and fights with potential predators.[6] Some displays of aggression include opening the mouth wide and hissing loudly.[6] It is known to be "the fiercest fighter of the opossums".[6] The gray four-eyed opossum is a nocturnal animal but can be active during the day. Although it is terrestrial, it is very good at climbing and swimming.[6] It has agile and swift movements, and seems more alert than other didelphids.[6]
Gray four-eyed opossums build nests out of dry leaves in hollow trees, tree forks, fallen logs and in ground burrows.[6] They roll up into a ball while sleeping and although their eyes are actually closed, the white patches of fur above their eyes gives them the appearance of an awake animal.[6]
Little is known about gray four-eyed opossums mating habits but they are in the family Didelphidae and so most likely to be polygynous.[5] This means males compete with other males. There are no courtship displays or pair bonds formed in didelphids.[5]
Reproduction is typically seasonal, with more young being born during the rainy season when there is an abundance of fruit.[5] During the dry season, fewer babies are born due to the lack of available fruit.[5] Litter sizes averaging between four and five young, with each female producing between two and four litters per year. Many young die while nursing in the mother's pouch.[5] This death rate is especially high during the dry season.[5] A major factor that determines survival of young is the mother's age; there are many deaths when the mother is less than 11 months.[6]
The average gestation period for the gray four-eyed opossum is 13 to 14 days, and each newborn weighs about 9 grams (0.32 oz).[5] They nurse in their mother's pouch until they are 68 to 75 days old.[5] Once weaned, they stay in their mother's nest for a further 8 to 15 days before their mother becomes aggressive and expels them.[5]
The gray four-eyed opossum has an omnivorous diet containing fruits, nectar, insects, small mammals (such as mice), birds, reptiles, amphibians, crustaceans, snails, and earthworms.[6] Its diet varies depending on the season.[6]
With such a varied diet, the gray four-eyed opossum will both encounter and eat venomous snakes. While the bites of these snakes may be harmful to most animals, the gray four-eyed opossum is able to overcome the toxic effects due to its immunity to the toxins.[7] The immunity was initially thought to come from an immune response leading to the production of antibodies, but in fact it comes from toxin-neutralizing proteins found in opossum serum.[7][8] These proteins are produced by the opossum prior to any encounter with a venomous snake, thus this immunity is not learned but inherited.[7]
The gray four-eyed opossum (Philander opossum) is an opossum species from Central and South America, ranging from southern Mexico to Peru, Bolivia and southwestern Brazil, at altitudes from sea level to 1600 m, but generally below 1,000 metres (3,300 ft). Its habitats include primary, secondary and disturbed forest. It is one of many opossum species in the order Didelphimorphia and the family Didelphidae.