Opossums Are From South America
(Possums Are From Australia)
Footprints of Monodelphis domestica
More than 60 species of opossums live in South America and 1 is found in North America. Most Americans are only familiar with that 1 very large opossum and are surprised to learn there are 60+ types...many of them smaller than the palm of your hand!
Despite the similarity in name, "Opossums" from South America and "Possums" from Australia are very different. Opossums received their name in 1612 from Captain John Smith of the Jamestown colony in Virginia. The word came from the Cherokee Indian name for the American animal. Possums received their name in 1770 from Captain Cook's botanist Sir Joseph Banks. He described an Australian common ringtail possum as "an animal of the Opossum tribe" based on their similar appearance. However, they are not closely related biologically. They are separated by 2 continents and 70+ million years.
The family of American opossums (called "Didelphidae") has 15 genera and 60+ species that range from North America to southern Argentina. Their sizes range from the tiny 40 gram mouse opossums to the large 2 kg opossum found in North America. Most opossums are solitary and nocturnal. They range from primarily terrestrial, to semi-arboreal, to almost fully arboreal.
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South American Opossums - Order Didelphidae |
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Caluromys Woolly Opossums derbianus, lanatus, philander |
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Caluromysiops Black-Shouldered Opossum irrupta |
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Chironectes Water Opossum minimus |
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Didelphis Large American Opossums albiventris, aurita, marsupialis, virginiana |
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Glironia Bushy-Tailed Opossum venusta |
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Gracilinanus Gracile Mouse Opossums aceramarcae, agilis, dryas, emiliae, longicaudus, marica, microtarsus, perijae |
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Lestodelphys Patagonian Opossum halli |
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Lutreolina Thick-Tailed Opossum crassicaudata |
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Marmosa Mouse Opossum andersoni, canescens, lepida, mexicana, murina, robinsoni, rubra, tyleriana, xerophila |
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Marmosops Slender Mouse Opossum cracens, dorothea, fuscatus, handleyi, impavidus, incanus, invictus, neblina, noctivagus, parvidens, pinheiroi, paulensis |
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Metachirus Brown Four-Eyed Opossum nudicaudatus |
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Micoureus Woolly Tailed Opossums alstoni, constantiae, demerarae, regina |
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Monodelphis Short-Tailed Opossums adusta, americana, brevicaudata, dimidiata, domestica, emiliae, iheringi, kunsi, maraxina, osgoodi, rubida, scalops, sorex, theresa, unistriata |
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Philander Four-Eyed Opossums andersoni, frenata, mcillhennyi, opossum |
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Thylamys Fat-Tailed Opossums elegans, macrura, pallidior, pusilla, velutinus, venusta |
Pouches
It is surprising to many people that dozens of marsupials do not have a pouch. Didelphis and Philander opossums have well-developed pouches. Both the male and female aquatic Chironectes opossums have a water-tight pouch. The other opossums have primitive protective folds of skin or do not have a pouch at all.
Opposable Big Toe
All opossums have an opposable "big toe" on their two hind feet, called a "hallux" that functions similarly to our thumbs. Their tails range from slightly to very prehensile, allowing them to use their tail like a fifth limb. Both the flexible toes and prehensile tails assist in helping them climb.
Prehensile Tail
Typically, the shorter the tail the more the opossum lives on the ground, and the longer the tail the more the opossum lives in the trees. The opossum species with the longest tails (exceeding the length of their entire bodies) can even hang from trees by their tail, or grab their own tails like a rope to "climb" up. Most construct nests of leaves and grass that they carry in their tails.
