The monito del monte or colocolo opossum, Dromiciops gliroides, also called chumaihu\xe9n in Mapudungun, is a diminutive marsupial native only to southwestern South America(Argentina and Chile). It is the only extant species in the ancient order Microbiotheria, and the sole New World representative of the superorder Australidelphia (all other New World marsupials are members of the paraphyletic Ameridelphia).



https://en.wikipedia.org/wiki/Monito_del_monte

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Seed-dispersing role

A study performed in the temperate forests of southern Argentina showed a mutualistic seed dispersal relationship between D. gliroides and Tristerix corymbosus, also known as the loranthacous mistletoe. The monito del monte is the sole dispersal agent for this plant, and without it the plant would likely become extinct. The monito del monte eats the fruit of T. corymbosus, and germination takes place in the gut. Scientists speculate that the coevolution of these two species could have begun 60–70 million years ago.