Marmosa Gray, 1821

Voss, Robert S., Fleck, David W. & Jansa, Sharon A., 2019, Mammalian Diversity And Matses Ethnomammalogy In Amazonian Peru Part 3: Marsupials (Didelphimorphia), Bulletin of the American Museum of Natural History 2019 (432), pp. 1-89 : 24-25

Marmosa Gray, 1821

Members of the genus Marmosa are among the most abundant species of nocturnal-arboreal insectivorous-frugivorous small mammals throughout lowland Amazonia. By contrast with previous classifications (e.g., in Gardner, 2005, 2008), the species referred to Marmosa are now allocated among five subgenera ( Voss et al., 2014). In the Yavarí-Ucayali interfluve, the nominotypical subgenus is represented by M. macrotarsus , the subgenus Micoureus by M. constantiae and M. rutteri , and the subgenus Stegomarmosa by M. lepida . In addition to these four species, M. (Eomarmosa) rubra might also be expected to occur in our region (appendix 2).

The Matses do not lexically distinguish the various species of small, long-tailed, blackmasked didelphids that occur in their tribal territory ( Hyladelphys kalinowskii , Marmosa spp. , Gracilinanus emiliae , Marmosops spp. ), but this seems as good a place as any to summarize relevant ethnological information.

ETHNOBIOLOGY: The opossums that the Matses call chekampi (“little opossums”) are superficially similar (small, black-masked, long-tailed, and pouchless), although some of our interviewees acknowledged that chekampi come in different sizes and in different shades of gray and brown. Some Matses use mapiokosëmpi (the name of the common opossum with a diminutive suffix) as an alternative name.

Mouse opossums come into Matses houses and eat their food. Sometimes they make nests in Matses houses, but they seldom stay long. The Matses say that mouse opossums usually enter their houses during heavy rains.

MATSES NATURAL HISTORY: Mouse opossums have long tails and large ears. Some are gray, while others are reddish, and others are darkcolored. They are similar to four-eyed opossums, but much smaller.

Mouse opossums are arboreal and terrestrial. They are abundant in the forest and sometimes come into Matses swiddens. They make nests of dry leaves in thick vegetation up in trees, in cavities in tree branches, or in leaf litter that accumulates in the crowns of palms. In Matses swiddens they make nests among plantain plants using dead plantain leaves. In houses they make nests in containers where clothes are kept.

Mouse opossums are strictly nocturnal. They give birth to many young. They always carry their young with them. Otherwise they are solitary.

Mouse opossums are eaten by margays and snakes. They make a high-pitched hiss when they are threatened.

Mouse opossums eat all sorts of things. They eat crickets/katydids; large cockroaches; and small birds, eggs, and hatchlings that they find at night in nests. They also eat dicot tree fruits, including those of the mannan tsipuis tree ( Inga spp. ; Mimosoideae ) and the mesocarp of swamppalm ( Mauritia flexuosa ) fruits.