| Bare-tailed woolly opossum | |
|---|---|
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Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Infraclass: | Marsupialia |
| Order: | Didelphimorphia |
| Family: | Didelphidae |
| Genus: | Caluromys |
| Species: | C. philander |
| Binomial name | |
| Caluromys philander | |
| Subspecies | |
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| Range of the bare-tailed woolly opossum | |
| Synonyms[2] | |
List
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Thebare-tailed woolly opossum (Caluromys philander) is anopossum fromSouth America. It was first described by Swedish zoologistCarl Linnaeus in 1758. The bare-tailed woolly opossum is characterized by a gray head, brown to gray coat, orange to gray underside and a partially naked tail. It isnocturnal (active mainly at night) and solitary; there is hardly any social interaction except between mother and juveniles and in mating pairs. The opossum constructs nests in tree cavities, and its litter size ranges from one to seven. Gestation lasts 25 days, and the juveniles exit the pouch after three months; weaning occurs a month later. The bare-tailed woolly opossum inhabitssubtropical forests, rainforests, secondary forests, and plantations; its range extends from northernVenezuela to northeastern and southcentralBrazil. TheIUCN classifies this opossum asleast concern.
It is calledmucura-xixica in Portuguese,zarigüeya lanuda parda in Spanish, andwakaro in theKwaza language ofRondônia, Brazil.[3]
The bare-tailed woolly opossum is one of the three members ofCaluromys, and is placed in the familyDidelphidae in themarsupial orderDidelphimorphia. It was firstdescribed by Swedish zoologistCarl Linnaeus asDidelphis philander in the10th edition ofSystema Naturae (1758). It was given its present binomial name,Caluromys philander, by American zoologistJoel Asaph Allen in 1900.[2][4] A 1955 revision of marsupial phylogeny groupedCaluromys,Caluromysiops,Dromiciops (monito del monte) andGlironia (bushy-tailed opossum) under a single subfamily, Microbiotheriinae, noting the dental similarities among these. A 1977 study argued that these similarities are the result ofconvergent evolution, and placedCaluromys,Caluromysiops andGlironia in a new subfamily,Caluromyinae.[5] In another similar revision in 2009, the bushy-tailed opossum was placed in its own subfamily, Glironiinae.[6]
The following four subspecies are recognized:[2][4]
Thecladogram below, based on a 2016 study, shows thephylogenetic relationships of the bare-tailed woolly opossum.[7]
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The bare-tailed woolly opossum is characterized by a brown to gray coat, gray head, orange to gray underside and a partially naked tail furry at the base.[8] A distinctive, narrow dark brown stripe runs between the eyes and the ears, from the tip of the nose to the back of the ears. Similar but broad streaks run from brown rings around either eye. Grayish fur separates these stripes from one another. Ears are large and almost always hairless. The coat is thick, soft and woolly; the flanks may be grayer than the back. The dorsal hairs continue up to 5–7 centimetres (2.0–2.8 in) onto the tail, after which it is naked, as the name suggests. The tail is dark brown towards the end, spotted with white and dark brown, terminating in a white or yellowish-white tip.[9]
The size appears to decrease fromVenezuela toSuriname; the mean weight is 170 grams (6.0 oz) in Venezuela and 250 grams (8.8 oz) in Suriname. The head-and-body length is typically between 16 and 26 centimetres (6.3 and 10.2 in). The ears measure 3 to 3.5 centimetres (1.2 to 1.4 in), the tail 25 to 36 centimetres (9.8 to 14.2 in) and the hind feet 3.2 to 3.9 centimetres (1.3 to 1.5 in).[8] Thedental formula is5.1.3.44.1.3.4 – typical of didelphids.[9]
The bare-tailed woolly opossum isnocturnal (active mainly at night), and thus difficult to observe or capture. Nevertheless, it is one of the very few opossums that have been successfully studied in detail. A study showed that activity of bare-tailed woolly opossums can be affected by the extent of moonlight. While activity in males dropped from new moon to full moon (that is, with increasing exposure to moonlight), activity in females remained largely unaffected.[10] The opossum isarboreal (tree-living) and a good climber.[9] A study showed that the tail, beingprehensile, can act as an additional limb for locomotion, avoiding falls and carrying leaves to build nests.[11] It builds nests with dry leaves in tree cavities.[8]
Individuals tend to be aggressive to one another; hisses, grunts and even distress calls accompany agonistic behavior. Largely solitary, the only interactions observed are between mother and juveniles and in a mating pair. In aprimary forest ofFrench Guiana, the meanhome range size was calculated as 3 hectares (0.012 sq mi). Ranges of both sexes overlapped extensively. The size of home ranges is influenced by environmental factors such as forage availability and individual needs.[12] 'Click's are a common vocalization, produced by the young as well as adults. Bare-tailed woolly opossums, like otherCaluromys species, will bite on being handled or to escape predators.[8] Predators include thejaguarundi andmargay.[13] The Bare-tailed woolly opossum is a host of theAcanthocephalan intestinal parasiteGigantorhynchus lutzi.[14]
Anomnivore, the bare-tailed woolly opossum feeds on fruits, vegetables,gum, flowers, nectar, arthropods (such as beetles, butterflies and other insects), other small invertebrates, small birds and reptiles.[8][9][15][16] A study of the foraging behavior of the bare-tailed woolly opossum and thesympatrickinkajou showed that both feed on a variety of plants, choose plants by their abundance, show similar preferences, and favor certain plant parts at certain times of the year. A notable difference between the two was that while the kinkajou focused on plants with a wide distribution, the bare-tailed woolly opossum also fed on less common plants.[17]
In French Guiana, females mate successfully after they are a year old. Females can have three litters a year, unless food is scarce.[8] Gestation lasts 25 days – the longest among didelphimorphs; the young come out of thepouch at three months and weaning occurs at four months.[18] A study in French Guiana showed that development of the offspring is slow for the first 40 days, and then accelerates during the last 40 days.[19] The litter size ranges from one to seven.[18] Newborn weigh 200 milligrams (0.0071 oz), and their weight increases to 11 grams (0.39 oz) after weaning.[20] After exiting the pouch, offspring are sheltered in nests, where the mother regularly visits them for nursing.[8]
The bare-tailed woolly opossum inhabitssubtropical forests, rainforests,secondary forests and plantations; it prefers dense cover, though it can be seen oncanopies as well. It can occur up to an altitude of 1,200–1,800 metres (3,900–5,900 ft) above the sea level. The range extends from northern Venezuela eastward to northeastern and southcentral Brazil, and includes Guiana, French Guiana,Margarita Island, Trinidad, and Suriname. TheIUCN classifies the bare-tailed woolly opossum asleast concern, due to its wide distribution and presumed large population. The survival of this opossum is threatened by deforestation and habitat loss.[1]
