Geographic Range
Monodelphis dimidiata
is native in northern Argentina, Paraguay, southern Brazil, and Uruguay (Gardner,
2007).
- Biogeographic Regions
- neotropical
Habitat
Monodelphis dimidiata
live in native grasslands of the region, but have been found in other habitats (Baladr贸n,
2012).
- Habitat Regions
- temperate
- Terrestrial Biomes
- savanna or grassland
Physical Description
Monodelphis dimidiata
is a small marsupial species. Their ventral side is yellowish and on their dorsal
side is grayish, with short ears, they are sexually dimorphic, with the males larger
than the females (Eisenberg 1989). Adult males body length is around 200 mm and weigh
around 90 g, adult females body length is around 170 mm and weigh around 50 g (Baladr贸n
2012).
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- male larger
Reproduction
It is not known when
Monodelphis dimidiata
breed; however, because the males are known to die in the summer after they mate
it is likely that they breed in the spring or early summer (Baladr贸n 2012).
Not a lot of information on
Monodelphis dimidiata
reproduction is known, only that they have one breeding season because they are semelparous.
Adult males die shortly after breeding, and adult females die after nurturing their
young (Baladr贸n 2012). It is likely the young are born small like other marsupials,
and have a short gestation period.
- Key Reproductive Features
- semelparous
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
Little is known about the parental investment of
Monodelphis dimidiata
. Adult females do survive until their young have been weaned and it is likely none
do not survive to mate in the next year (Baladr贸n 2012). Being semelparous and most
adult males likely dying before their young have been born,it is likely that all parental
investment is done by the females (Baladr贸n 2012).
- Parental Investment
- altricial
- female parental care
Lifespan/Longevity
Being semelparous
Monodelphis dimidiata
only lives for about one year, males have shorter lifespans and die shortly after
breeding, females die after rearing their young (Baladr贸n 2012).
Behavior
Information on
Monodelphis dimidiata
is unknown but they are likely fossorial as they primarily are found in grasslands,
they are also likely solitary like many other Didelphidae (Martina 2013).
Home Range
The home range of Monodelphis dimidiata is unknown.
Communication and Perception
Monodelphis dimidiata uses smell as its main sense, it also makes vocal communication like other Didelphidae (Gonz谩lez 2000).
Food Habits
Monodelphis dimidiata
individuals primarily eat insects but have been known to eat arachnids, earthworms,
isopods, and mollusks, it also has been reported to eat small mammals, and plants
(Hume 1999).
- Primary Diet
- carnivore
- Animal Foods
- mammals
- insects
- terrestrial non-insect arthropods
- mollusks
- terrestrial worms
Predation
Little information is known about
Monodelphis dimidiata
anti-predator adaptations but since
Monodelphis dimidiata
lives primarily in grasslands, its grayish back likely provides some camouflage.
Monodelphis dimidiata
has been found in the stomachs of Barn Owls (
Tyto alba
) and White-tailed Kites (
Elanus leucurus
) (Scheibler 2007).
- Anti-predator Adaptations
- cryptic
Ecosystem Roles
Monodelphis dimidiata
has a negative impact on the insects and other animals it eats, it also has a positive
effect on the animals like
Tyto alba
and
Elanus leucurus
that have been known to eat
Monodelphis dimidiata
(Gonz谩lez 2000).
Economic Importance for Humans: Positive
There are no known positive effects of Monodelphis dimidiata on humans
Economic Importance for Humans: Negative
There are no known negative consequences of Monodelphis dimidiata on humans.
Conservation Status
This species is listed as Least Concern according to the IUCN Red List, but
Monodelphis dimidiata
has been reported to be in decline due to the loss of native grassland to agriculture
(Brito et al., 2011).
Additional Links
Contributors
Samuel Duskey (author), Miami University, Joseph Baumgartner (editor), Miami University, Tanya Dewey (editor), University of Michigan-Ann Arbor.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- tropical savanna and grassland
-
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
- savanna
-
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
-
A terrestrial biome found in temperate latitudes (>23.5掳 N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
- 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.
- 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.
- semelparous
-
offspring are all produced in a single group (litter, clutch, etc.), after which the parent usually dies. Semelparous organisms often only live through a single season/year (or other periodic change in conditions) but may live for many seasons. In both cases reproduction occurs as a single investment of energy in offspring, with no future chance for investment in reproduction.
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- altricial
-
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
- female parental care
-
parental care is carried out by females
- motile
-
having the capacity to move from one place to another.
- solitary
-
lives alone
- visual
-
uses sight to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- cryptic
-
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- tactile
-
uses touch to communicate
- chemical
-
uses smells or other chemicals to communicate
References
Baladr贸n, A., A. Malizia, M. B贸, M. Li茅bana, M. Bechard. 2012. Population dynamics of the southern short-tailed opossum (Monodelphis dimidiata) in the Pampas of Argentina. Australian Journal of Zoology , 60/4: 238-245.
Brito, D., J. Vilela, D. Flores, P. Teta. 2011. " Monodelphis dimidiata " (On-line). The IUCN Red List of Threatened Species.. Accessed May 07, 2015 at http://www.iucnredlist.org/details/13693/0 .
Eisenberg, J. 1989. Mammals of the Neotropics . Chicago: University of Chicago Press.
Gardner, A. 2007. Mammals of South America . Chicago: University of Chicago Press.
Gonz谩lez, E., S. Claramunt. 2000. Behaviors of captive short-tailed opossums, Monodelphis dimidiata. Mammalia , 64/3: 271-286.
Hume, I. 1999. Marsupial Nutrition . New York: Cambridge University Press.
Martina, L. 2013. "Didelphidae American opossums and opossums" (On-line). Accessed May 05, 2015 at http://animaldiversity.org/accounts/Didelphidae/ .
Scheibler, D. 2007. Habitat associations of small mammals in southern Brazil and use of regurgitated pellets of birds of prey for inventorying a local fauna.. Brazilian Journal Of Biology , 67/4: 619.