Gracilinanus agilisagile gracile mouse opossum
Geographic Range
This opossum is found from eastern Brazil to eastern Peru and northern Argentina.
- Biogeographic Regions
- neotropical
Habitat
This opossum lives in forest habitats.
- Terrestrial Biomes
- forest
- rainforest
Physical Description
Head-body length averages 110 mm while tail length averages 137 mm. Males and females are similar in size. Their tails are naked and prehensile. Mouse opossums have an opposable big toe on their hind feet, which allows them to rapidly climb thin vines. Their opposable toes lack claws. They have very mobile, membraneous ears.
- Other Physical Features
- endothermic
- bilateral symmetry
Reproduction
Females produce two litters annually. A female's first estrus occurs at 265-75 days. Gestation lasts about 20 days. A female has 13 teats, but not all teats are functional. The maximum litter size is 11; average 7-9. The weight of each newbornis less than 250 mg, and the young are extremely altricial at birth. This species lacks a pouch. After the young are born, they crawl up the mother's belly and attach themselves to a nipple. Weaning occurs at 60-70 days. The young leave the mother a few days after they have been weaned.
- Key Reproductive Features
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
Lifespan / Longevity
-
- Average lifespan
Status: captivity - 6.1 years
- AnAge
- Average lifespan
Behavior
These opossums are solitary animals. They hunt and nest alone. They live in dens or in nests that they have taken over from other species.
- Key Behaviors
- motile
Communication and Perception
Food Habits
These opossums are omnivores, feeding mainly on insects and soft fruits. They are nocturnal.
Conservation Status
-
- IUCN Red List
-
Least Concern
More information
Other Comments
When threatened, this opossum feigns death. Because they are nocturnal, hearing is an important sense.
This particular species is occasionally found as stowaways in banana shipments. When bananas are shipped, they are kept at a relatively cool temperature. Mouse opossums fall into a hibernation-like state at low temperatures. Their respiration rate, metabolism, and need for food are decreased, allowing them to survive the cool temperature of the banana shipments.
Contributors
Allison Rogers (author), University of Michigan-Ann Arbor.
Glossary
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- chemical
-
uses smells or other chemicals to communicate
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- motile
-
having the capacity to move from one place to another.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- rainforest
-
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- tactile
-
uses touch to communicate
References
Grizmek's Encyclopedia of Mammals. 1990. V.1. McGraw-Hill Publishing Company, New York.
Lee, A. L. & Cockburn, A. 1985. Evolutionary Ecology of Marsupials. Cambridge University Press, Cambridge.
McGraw-Hill Encyclopedia of Science and Technology. 1992. V.12.
The New Encyclopedia Brittania. 1994. V.8.
Nowak, R. M. 1991. Walker's Mammals of the World. V.1. The Johns Hopkins University Press, Baltimore.
Stonehouse, B. & Gilmore, D. 1977. The Biology of Marsupials. University Park Press, Baltimore.
Tyndale-Biscoe, H. 1973. Life of Marsupials. American Elsevier Publishing Company, Inc., New York.