Philander Brisson, 1762

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 : 52-54

Philander Brisson, 1762

Two species of gray four-eyed opossums, Philander mcilhennyi and P. pebas , are definitely known to occur in the Yavarí-Ucayali interfluve, and a third species ( P.canus ) could be expected to occur there based on geographic range data (appendix 2). Specimens of both P. pebas and P. canus have long been misidentified as P. opossum (an eastern-Amazonian taxon; Voss et al., 2018), so the identity of animals previously reported as P. opossum from the Yavarí-Ucayali interfluve ( Pavlinov, 1994; Fleck and Harder, 1995) is unclear. To facilitate the identification of specimens collected in the course of future fieldwork, we summarize qualitative traits and morphometric variation for all three species (tables 19–21).

The Matses do not consistently recognize more than a single kind of opossum with pale supraocular spots, so the name they apply to such animals, cheka bëbëdi, could refer either to gray four-eyed opossums or to the superficially similar brown four-eyed opossum ( Metachirus myosuros ). Because species of Philander are more commonly encountered than M. myosuros , we summarize relevant ethnographic information here.

ETHNOBIOLOGY: Cheka bëbëdi, the most frequently used name for these species, literally means “spotted-forehead opossums,” but in some Matses villages they are called cheka dëwisak “long-snouted opossums.” They are sometimes also referred to as chekadapa “big opossum,” but this is not considered a real name; rather it is a descriptive phrase used to distinguish these large species from mouse opossums. Some Matses recognize that there is more than one local type of cheka bëbëdi, but they do not differentiate them linguistically.

The Matses do not eat these opossums, although children sometimes shoot them with arrows. One informant mentioned that a foureyed opossum ate his pet dove.

MATSES NATURAL HISTORY: Some foureyed opossums are black, while others are gray,

TABLE 20

and others are reddish/yellowish. They have a very long tail, a long snout, spots on their foreheads, and long whiskers.

They are arboreal and terrestrial. They are common in all rainforest habitats but seem to be more common along streams.

Four-eyed opossums make nests in different places: in the leaf litter that collects at the base of large stemless palms; in hollow logs; in vine tangles up in the trees; on the ground at the base of two trees that are growing right next to each other; and in the crown of plantain plants. These they line with dry leaves.

Four-eyed opossums are nocturnal.

Four-eyed opossums have many young, which they carry around and suckle inside their pouches. The young leave the mother when they get about half the size of the mother. Other than mothers with young, they are solitary.

Four-eyed opossums are eaten by margays and ocelots.

Four-eyed opossums open their mouth very wide and hiss aggressively when found by people, and try to bite them if they get close.

Four-eyed opossums eat anything. They eat sweet tree fruits, the mesocarp of swamp-palm ( Mauritia

TABLE 21

flexuosa ) fruits, crickets/katydids, spiders, and armored millipedes. They eat birds that they find nesting up in the trees or on the ground. If the bird flies off or is too large, they eat the eggs or hatchlings. Among the birds they prey upon are tinamous, ground doves, and rusty-belted tapaculos.