Brazilian gracile opossum habitats than more purely arboreal animals. It has also been found in artificial plantations. There are no recognised subspecies. Brazilian gracile opossums are arboreal and nocturnal, spending the day nesting in tree hollows. They are solitary animals, with each individual inhabiting a home range of anything from , depending on habitat. Males tend to have larger home ranges than females, presumably because, being larger, they require more food. The species is insectivorous, and is an opportunistic forager, not specialising in any particular kind of insect. Individuals have also been reported to eat some spiders, snails, and even fruit (including passionfruit).
Long-tongued arboreal mouse because of its tolerance of several types of habitats, and because in the absence of any particular threats, it seems unlikely that it is declining at a sufficient rate to qualify for being included in a more threatened category. Long-tongued arboreal mouse The long-tongued arboreal mouse ("Rhagomys longilingua") is a South American rodent species of the family Cricetidae. It is found in a variety of habitats, including dense forest, in Bolivia and Peru at elevations from on the eastern side of the Andes. The species is at least partly arboreal. It is distinguished from the Brazilian arboreal mouse ("R. rufescens"),