Marmosa rubrared mouse opossum

Geographic Range

Marmosa rubra is an Amazonian species that occurs in southeastern Colombia, eastern Ecuador, and eastern Peru. (Rossi, et al., 2010)


The natural habitat throughout the known distribution of this species is lowland or premontane tropical rainforest. Specimens have been collected from 180 to 730 m above sea level. (Rossi, et al., 2010)

  • Range elevation
    180 to 730 m
    590.55 to 2395.01 ft

Physical Description

Like other species of mouse opossums, Marmosa rubra 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 reddish brown and the ventral fur is orangish. Among other diagnostic traits, this species differs from other species of Marmosa by lacking distinct postorbital processes, lacking palatine fenestrae, and lacking a gular gland. Because the species is seldom collected, sample sizes for measurements and weights are small, so the maximum and minimum values provided are unlikely to represent the full range of adult variability. It is not known if this species exhibits sexual size dimorphism or not. (Rossi, et al., 2010)

  • Range mass
    59 to 81 g
    2.08 to 2.85 oz
  • Range length
    128 to 200 mm
    5.04 to 7.87 in


Nothing is known about the mating system of this species.

Very little is known about reproduction in Marmosa rubra, but other species of Marmosa are spontaneous ovulators that give birth to very altricial young after a short gestation. Females have seven to nine mammae, so litters are likely to consist of nine or fewer young. (Rossi, et al., 2010)

  • Key Reproductive Features
  • iteroparous
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual
  • Average number of offspring

Nothing is known about parental investment in this species, but female opossums of other species nurse their young, protect them from predators, and groom them before they are weaned.

  • Parental Investment
  • altricial
  • female parental care
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female


Nothing is known about the longevity of this species in the wild or in captivity.


Nothing is known about the behavior of this species, but other species of Marmosa are known to be arboreal/scansorial, solitary, and nocturnal. (Tate, 1933)

Home Range

No published data on home range of this species exist.

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. Unlike other species of Marmosa, M. rubra is not known to have cutaneous glands that might be used for scent marking. (Rossi, et al., 2010)

Food Habits

The dentition of this species resembles that of other closely related opossums known to eat insects and fruit.

  • Animal Foods
  • insects
  • Plant Foods
  • fruit


Nothing seems to be known about the natural predators of this species, but they probably include snakes, owls, and wild felids. (Tate, 1933)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Marmosa rubra 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 importance.

Economic Importance for Humans: Negative

There are no known adverse effects of Marmosa rubra on humans.

Conservation Status

Marmosa rubra is very widely distributed in a region that is still largely undeveloped. (Rossi, et al., 2010)

Other Comments

Maximum-likelihood analysis of mitochondrial DNA sequence data suggest that Marmosa rubra is the sister taxon of a group of species that includes M. simonsi, M. xerophila, M. robinsoni, M. isthmica, M. zeledoni, and M. mexicana. Virtually nothing is known about its natural history. (Gutierrez, et al., 2010)


Robert Voss (author), American Museum of Natural History, Sharon Jansa (editor), American Museum of Natural History, Alexa Unruh (editor), Animal Diversity Web Staff.



living in the southern part of the New World. In other words, Central and South America.

World Map


uses sound to communicate


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.


Referring to an animal that lives in trees; tree-climbing.

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.


an animal that mainly eats meat


uses smells or other chemicals to communicate


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.


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.

female parental care

parental care is carried out by females


An animal that eats mainly insects or spiders.


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).


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.


active during the night


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.


reproduction that includes combining the genetic contribution of two individuals, a male and a female


lives alone


uses touch to communicate


Living on the ground.


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


uses sight to communicate


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.