The Brazilian gracile opossum (''Gracilinanus microtarsus'') is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of small
opossum
Opossums () are members of the marsupial order Didelphimorphia () endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 93 species in 18 genera. Opossums originated in South America and entered North ...
from
Brazil
Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
.
Description
Brazilian gracile opossums are relatively small opossums, with males ranging from and females from in head-body length. The tail is between 30 and 50% of the head-body length. Males weigh and females from .
The opossum is reddish dark brown or grey over most of its body with paler, cream-colored, underparts. The fur on the face is also relatively pale, with distinct rings of near black fur around each eye. The tail is prehensile and scaly, and does not store fat as it does in some related species. The toes are relatively long, with small, regular, claws. The female typically has fifteen teats, although the exact number can vary; four are on the chest, and the remainder, including a single median teat, on the abdomen.
Distribution and habitat
The Brazilian gracile opossum is found only in Brazil, being endemic to the south-eastern parts of the country, from
Espirito Santo
''Espirito'' (Brazilian for "Spirit") is the second album by Lawson Rollins. Rollins composed all of the music and co-produced the album with Persian-American musician and producer Shahin Shahida (of Shahin & Sepehr) and multi-platinum producer Do ...
to
Rio Grande do Sul
Rio Grande do Sul (, , ; "Great River of the South") is a Federative units of Brazil, state in the South Region, Brazil, southern region of Brazil. It is the Federative_units_of_Brazil#List, fifth-most-populous state and the List of Brazilian st ...
.
[ It inhabits rainforests and partly deciduous forests scattered in the southern regions of the ]cerrado
The ''Cerrado'' (, ) is a vast ecoregion of tropical savanna in eastern Brazil, particularly in the states of Goiás, Mato Grosso do Sul, Mato Grosso, Tocantins, Minas Gerais, and the Federal District. The core areas of the Cerrado biome are t ...
ecoregion, but, being able to forage successfully on the ground, is less affected by fragmentation of forest habitats than more purely arboreal animals.plantation
A plantation is an agricultural estate, generally centered on a plantation house, meant for farming that specializes in cash crops, usually mainly planted with a single crop, with perhaps ancillary areas for vegetables for eating and so on. The ...
s.
There are no recognised subspecies.
Behavior
Brazilian gracile opossums are arboreal and nocturnal
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
, 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
A robber fly eating a hoverfly
An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects.
The first vertebrate insectivores were ...
, 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
''Passiflora edulis,'' commonly known as passion fruit, is a vine species of passion flower native to southern Brazil through Paraguay and northern Argentina. It is cultivated commercially in tropical and subtropical areas for its sweet, seedy f ...
). Predators of Brazilian gracile opossums include ocelot
The ocelot (''Leopardus pardalis'') is a medium-sized spotted wild cat that reaches at the shoulders and weighs between on average. It was first described by Carl Linnaeus in 1758. Two subspecies are recognized. It is native to the southwes ...
s, oncilla
The oncilla (''Leopardus tigrinus''), also known as the northern tiger cat, little spotted cat, and tigrillo, is a small spotted cat ranging from Central America to central Brazil. It is listed as Vulnerable on the IUCN Red List, and the popul ...
s, crab-eating fox
The crab-eating fox (''Cerdocyon thous''), also known as the forest fox, wood fox, bushdog (not to be confused with the bush dog) or maikong, is an extant species of medium-sized canid endemic to the central part of South America since at least ...
es, maned wolves
The maned wolf (''Chrysocyon brachyurus'') is a large canine of South America. It is found in Argentina, Brazil, Bolivia, Peru, and Paraguay, and is almost extinct in Uruguay. Its markings resemble those of foxes, but it is neither a fox nor a w ...
and white-tailed hawk
The white-tailed hawk (''Geranoaetus albicaudatus'') is a large bird of prey species found in tropical and subtropical environments of the Americas.
Description
The white-tailed hawk is a large, stocky hawk. It is close in size to the Swainso ...
s.[
]
Reproduction
Females come into estrus
The estrous cycle (, originally ) is the set of recurring physiological changes that are induced by reproductive hormones in most mammalian therian females. Estrous cycles start after sexual maturity in females and are interrupted by anestrous p ...
once a year, between August and September. Litters of up to twelve young are born during the wet season, when food is plentiful. The mother does not possess a pouch. They are weaned
Weaning is the process of gradually introducing an infant human or another mammal to what will be its adult diet while withdrawing the supply of its mother's milk.
The process takes place only in mammals, as only mammals produce milk. The infan ...
by three months of age, between November and December. The young are fully grown, with an adult set of teeth, by six months, reaching sexual maturity within a year of birth. Most Brazilian gracile opossums do not survive for much longer than a year, but some can reach two years of age.
References
{{Taxonbar, from=Q194850
Opossums
Endemic fauna of Brazil
Fauna of the Atlantic Forest
Marsupials of South America
Mammals of Brazil
Environment of Rio de Janeiro (state)
Environment of São Paulo (state)
Mammals described in 1842