Opossums are members of the marsupial order Didelphimorphia endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 126 species in 18 genera. Opossums originated in South America and entered North America in the Great American Interchange following the connection of North and South America.
The Chacoan pygmy opossum is a recently described genus and species of didelphimorph marsupial. The only species in Chacodelphys, C. formosa, was known until 2004 from only one specimen collected in 1920 in the Chaco of Formosa Province, Argentina. The species is gaining popularity as a pocket pet.
Monodelphis is a genus of marsupials in the family Didelphidae, commonly referred to as short-tailed opossums. They are found throughout South America. As of January 2019, the most recently described species is M. vossi.
The gray short-tailed opossum is a small South American member of the family Didelphidae. Unlike most other marsupials, the gray short-tailed opossum does not have a true pouch. The scientific name Monodelphis is derived from Greek and means "single womb" and the Latin word domestica which means "domestic". It was the first marsupial to have its genome sequenced. The gray short-tailed opossum is used as a research model in science, and is also frequently found in the exotic pet trade. It is also known as the Brazilian opossum, rainforest opossum and in a research setting the laboratory opossum.
The northern red-sided opossum or the Guianan short-tailed opossum, Monodelphis brevicaudata, is an opossum species from South America. It is found in Bolivia, Brazil. French Guiana, Guyana, Suriname and Venezuela.
The yellow-sided opossum is an opossum species from South America. It is found in Argentina, Brazil and Uruguay. They have grey or black fur on their dorsal side with yellowish fur on the lateral side that continues down to the feet. They are the most mysterious of all the Monodelphis that is found specifically in the Pampean region or Pampa of Argentina. It is suspected to be a once-in-a-lifetime breeder as seen in a three-year observational study of one population in the marshy grasslands of the Pampean region. Maintaining their native grasslands is important for them to keep a stable population. They show sexual dimorphism in overall size: adult males are typically 100-150 g whereas adult females are 30-70 g.
Emilia's short-tailed opossum is an opossum species from South America. It is found south of the Amazon River from eastern Peru, through Bolivia, to central Brazil.
Ihering's three-striped opossum, is an opossum species found in Argentina and Brazil.
The pygmy short-tailed opossum, scientifically named Monodelphis kunsi, is an opossum species from South America. M. kunsi is a marsupial from the family Didelphidae of the order Didelphimorphia. Although it is a marsupial, it lacks the characteristic pouch that is often associated with this order. It is found in Argentina, Bolivia, Brazil and Paraguay. M. kunsi is considered a smaller species within the family Didelphidae, which is why it is named a pygmy opossum. The young are referred to as 'joeys'. The females are referred to as 'Jill,' and the males 'jack'. It was thought to have been endangered in 2001, but has since been moved to least concern by the International Union for Conservation of Nature.
The long-nosed short-tailed opossum is an opossum species in Argentina and Brazil.
The one-striped opossum is a possibly extinct opossum species from South America. It is known only from two specimens found in Brazil in 1821 and Argentina in 1899.
The sepia short-tailed opossum is a species of opossum in the family Didelphidae found in Colombia, Ecuador, Panama, Peru and Venezuela.
Osgood's short-tailed opossum is a species of opossum in the family Didelphidae. It is found in Bolivia and Peru. Its natural habitats are subtropical or tropical moist lowland forest and subtropical or tropical dry lowland grassland. It is threatened by habitat loss. The opossum is named after American zoologist W. H. Osgood.
The Amazonian red-sided opossum is a South American opossum species of the family Didelphidae, formerly viewed as part of M. brevicaudata. It is found in Bolivia, Brazil and Peru, where it inhabits the Amazon rainforest. It is omnivorous, nocturnal, and primarily nonarboreal.
The hooded red-sided opossum is a South American opossum species of the family Didelphidae. Until recently, it was viewed as a subspecies of M. brevicaudata. It is found in Colombia and Venezuela at altitudes from sea level to 2250 m. It is a primarily nonarboreal resident of tropical rainforest, but has also been seen in areas under cultivation.
Ronald's opossum is a South American opossum species of the family Didelphidae. It was discovered in 2004, and most closely resembles M. adusta. It is known only from Manú National Park, Peru, where it inhabits the Amazon rainforest. It is named after American zoologist Ronald H. Pine.
Reig's opossum is a South American opossum species of the family Didelphidae, discovered in 2004. It is named after Argentine biologist Osvaldo Reig (1929–1992). It was initially found in montane forest in Canaima National Park, Venezuela at an elevation of 1300 m in the Sierra de Lema. It is typically found between 1100 m and 2050 m on Mount Ayanganna.
