Geographic Range
Marmosa mexicana
occurs from eastern Mexico southward throughout much of Central America to eastern
Panama, from near sea level to about 2090 m.
- Biogeographic Regions
- neotropical
Habitat
Marmosa mexicana
(which may include more than one species; see Other Comments) occurs in a very wide
range of habitats, including dry (deciduous) thorn forest, evergreen lowland forest,
pine-oak woodlands, and mangroves; it is known to occur both in undisturbed situations
and in secondary growth.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- forest
- rainforest
- scrub forest
- mountains
Physical Description
Like other species of
mouse opossums
,
Marmosa mexicana
is a small, pouchless marsupial with large, membranous ears; prominent eyes; a mask
of dark fur surrounding the eyes, and a long, slender, prehensile tail. The dorsal
fur is usually some shade of reddish brown and the ventral fur is yellowish to orangish.
Among other diagnostic traits, this species differs from other species of
Marmosa
by its extensive blackish facial mask, which extends well behind the eye to the base
of the ear on each side of the head. This species is sexually dimorphic (males average
larger than females).
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- male larger
Reproduction
Nothing is known about the mating system of this species.
Almost nothing has been published about reproduction that can be confidently attributed
to
Marmosa mexicana
, but other species of
Marmosa
are spontaneous ovulators that give birth to highly altricial young after a short
gestation (see
M. robinsoni
). Several descriptions of reproduction by female
mouse opossums
found on banana boats in the early 20th century and identified as
M. mexicana
(see references cited by Alonso-Mejia and Medellin, 1992) are unvouchered and might
have been based on other species. Museum specimens of
M. mexicana
have 11 to 15 functional mammae, so average litter sizes are probably in this range.
- Key Reproductive Features
- iteroparous
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
Although parental care has not been observed in this species, females presumably nurse
neonatal young, groom them, and protect them from predators, but other forms of parental
investment are unknown.
- Parental Investment
- altricial
- female parental care
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
Lifespan/Longevity
Nothing is definitely known about the lifespan of
Marmosa mexicana
, but other species of
Marmosa
that have been studied in the wild are not thought to live much longer than one year.
Captives might live longer, but no published information about captive lifespan is
available.
Behavior
There have been no published studies of behavior that can be definitely attributed
to this species, but other species of
Marmosa
are arboreal/scansorial, nocturnal, and solitary. Alleged burrowing behavior may
be based on animals found nesting in cavities excavated by other species (the forepaws
of this species are conspicuously unsuited for burrowing).
Home Range
There have been no published studies of the home range of this species.
Communication and Perception
The eyes, ears, nasal turbinates (thin bones that support olfactory epithelium), and
tactile hairs are well developed in this species (as in other opossums), so vision,
hearing, and touch are probably important senses. Which of these are actually used
for communication with other conspecifics is unknown.
Food Habits
Little definite information is available about the food habits of this species, but
its dentition is similar to that of other species of
Marmosa
which are known to be insectivorous and to eat fruit occasionally. Anecdotal reports
suggests that it also eats, at least occasionally, bird's eggs and small vertebrates.
- Primary Diet
- carnivore
- Animal Foods
- birds
- mammals
- reptiles
- eggs
- carrion
- insects
- Plant Foods
- fruit
Predation
The natural predators of this species probably include
snakes
,
owls
, and wild
felids
. Bones of
Marmosa mexicana
have been recovered from pellets of two species of
owls
.
- Anti-predator Adaptations
- cryptic
Ecosystem Roles
Marmosa mexicana is probably a primary consumer (of fruit) and a secondary consumer (of insects ). It is probably eaten by snakes , owls , and carnivorans ; and it is certainly host to many species of invertebrate ecto- and endo-parasites. Probable ectoparasites include species of Arachnida ( Acari : mites) and Insecta ( Siphonaptera : fleas). Probable endoparasites include species of Acanthocephala (spiny-headed worms), Cestoda (tapeworms), Digenea (flukes), and Nematoda (roundworms).
Economic Importance for Humans: Positive
It is unlikely that this species is of any positive economic value to humans.
Economic Importance for Humans: Negative
There are no known adverse effects of Marmosa mexicana on humans.
Conservation Status
Marmosa mexicana
is a species of Least Concern according to the IUCN Red List. Because
M. mexicana
is very widely distributed in a wide range of habitats including human-modified vegetation,
it does not require protection.
Other Comments
Until 2010
Marmosa mexicana
was confused with
M. zeledoni
, a distinct species, so unvouchered ecological or behavioral observations from areas
where these species occur sympatrically (Nicaragua, Costa Rica, and Panama) cannot
be confidently associated with either species. Even as restricted by Rossi et al.
(2010),
M. mexicana
may consist of more than one species. Two distinct mitochondrial haplotype lineages
(called
M. mexicana A
and
M. mexicana B
) were identified by Gutierrez et al. (2010), who discussed the possibility that they
might represent different species.
Additional Links
Contributors
Robert Voss (author), American Museum of Natural History, Sharon Jansa (editor), American Museum of Natural History, Alexa Unruh (editor), Animal Diversity Web Staff.
- 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.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- 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.
- scrub forest
-
scrub forests develop in areas that experience dry seasons.
- mountains
-
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
- 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.
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a 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
- arboreal
-
Referring to an animal that lives in trees; tree-climbing.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- solitary
-
lives alone
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- carrion
-
flesh of dead animals.
- 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.
References
Alonso-Mejia, A., R. Medellin. 1992. Marmosa mexicana . Mammalian Species , 421: 1-4.
Gutierrez, E., S. Jansa, R. Voss. 2010. Molecular systematics of mouse opossums (Didelphidae: Marmosa ): assessing species limits using mitochondrial DNA sequences, with comments on phylogenetic relationships and biogeography. American Museum Novitates , 3692: 1-22.
Rossi, R., R. Voss, D. Lunde. 2010. A revision of the didelphid marsupial genus Marmosa . Part 1. The species in Tate's ' mexicana ' and ' mitis ' sections and other closely related forms. Bulletin of the American Museum of Natural History , 334: 1-81.
Tate, G. 1933. A systematic revision of the marsupial genus Marmosa . Bulletin of the American Museum of Natural History , 66: 1-250.