Philander frenatus

Geographic Range

The distribution of Philander frenatus , the southeastern four-eyed opossum, extends from coastal and inland southeastern Brazil to eastern Paraguay, including the portion of Argentina in between.

• Biogeographic Regions
• neotropical neotropical
  • native native

Habitat

Philander frenatus is found in lowland evergreen rainforests throughout its range. This species is found in both undisturbed and disturbed areas, and individuals can move between habitat fragments in fragmented landscapes. Individuals prefer areas with high amounts of leaf litter, most likely because leaf litter houses small invertebrates, which are common prey items. Philander frenatus individuals build their nests in rocky areas, usually near running water, if it is available.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• rainforest rainforest

Physical Description

Like all species of the genus Philander , this species has lighter spots above the eyes, giving the appearance of “four eyes.” It also has a slim body and a relatively large head with a long, conical-shaped muzzle. All species in this genus also have slim, partially furred prehensile tails that are equal to or longer than the body length. Individuals have opposable pollex on the forefeet and opposable hallux on the hindfeet. Females have fully developed pouches.

Philander frenatus has a total body length (head to tip of tail) of 230-620 mm and tail length of 170-320 mm. It has gray fur on its back and sides with pale cream-gray fur on the ventrum and a sharp transition between the two colors. Some individuals have darker coloration on their back in comparison to their sides, but there is never a distinct band running from the head to the tail.

The distribution of P. frenatus overlaps with the physically similar Philander opossum canus along the Paraguay River in Paraguay and Brazil; however, P. frenatus can be distinguished by a postorbital constriction wider than 10.5 mm.

• Other Physical Features
• endothermic endothermic
• bilateral symmetry bilateral symmetry

Reproduction

Reproduction in Philander frenatus is thought to be seasonal, and lactating females have been caught in July through March in Brazil, with an average of 5.4 young. In a study performed by Hingst et al. (1998), captive P. frenatus females reproduced in August through February. The captive females each had 1-10 young (mean 5.5) at the time of birth, after a 13-14 day gestation period. No more than 7 young survived the first day, as all females had only 7 teats. At weaning, which was 70-80 days after birth, the average litter size was 4 young. Females raised in captivity first reproduced 352 days after birth, on average, while males raised in captivity first reproduced at 282 days, on average.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• viviparous viviparous

Few studies have been performed on P. frenatus parental investment, but Philander opossum young stay in the nest 8-15 days post-weaning, and after this period the female is indifferent or aggressive to her young.

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

Lifespan/Longevity

Little is known about the lifespan of P. frenatus , but the average lifespan of Philander opossum is 2.5 years in the wild and 3.5 years in captivity.

Behavior

Philander frenatus is a scansorial and terrestrial opossum. It has the ability to jump up to 60 cm and will climb up to 8 m into the understory, but is not found climbing in trees often. It is nocturnal and solitary and is not known to be territorial. This species is thought to rely on visual queues for orientation.

• Key Behaviors
• scansorial
• terricolous
• nocturnal nocturnal
• motile motile
• solitary solitary

Home Range

One radiotelemetry study by Lira and Fernandez (2009) found that Philander frenatus individuals in an Atlantic forest in Brazil maintain a home range of 0.6-7.4 ha. There was no significant difference in home range size between males and females. Another study by Gentile and colleagues (2004) found a P. frenatus population density of 0.17-0.92 individuals/ha of forest near Garafão, Rio de Janeiro.

Communication and Perception

Although little is known about P. frenatus communication and perception, it is known that the closely related P. opossum uses at least three sounds to communicate: a clicking sound, a hiss when threatened, and a squeak, which may be used as a mating call by females. 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 senses is actually used for communication is unknown.

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Philander frenatus is omnivorous, consuming birds, mammals, reptiles, invertebrates, and fruits. Studies in Brazil found that, of all individuals caught, 29-81% had eaten fruits, 20-57% had eaten small vertebrates, and 94-100% had eaten invertebrates. This indicates that invertebrates, especially from the orders Coleoptera , Opiliones , Diplopoda , and Blattariae , are an important food source for P. frenatus in Brazil. Juveniles consume less vertebrates, perhaps because of their smaller size and inability to subdue vertebrate prey. All age classes ate more fruits during the wet season.

A similar study performed by Macedo and collegues (2010) in two forest fragments of Brazil found that the diet of P. frenatus also consisted largely of Hymenoptera , Arachnida , and carrion. They also found seeds belonging to pioneer plant species in P. frenatus fecal matter, confirming that this species uses and forages in areas disturbed by humans.

• Primary Diet
• omnivore omnivore

• Animal Foods
• birds
• mammals
• amphibians
• reptiles
• carrion carrion
• insects
• terrestrial non-insect arthropods
• mollusks
• aquatic crustaceans

• Plant Foods
• fruit

Predation

There are no known predators of P. frenatus , but, like the closely related Philander opossum , it is most likely preyed upon by wild felids, wild mustelids, foxes, large owls, and large snakes. In fact, remains of P. opossum have been found in the feces of the viper Bothrops asper . Opossums of the species P. opossum are also occasionally consumed by humans in Guyana, and P. frenatus could also be a food source for humans.

Ecosystem Roles

Species in the genus Philander have been known to host many endoparasites including viruses, protozoans, fungi, roundworms (Nematoda), flukes (Trematoda), and tapeworms (Cestoda) and ectoparasites including lice (Mallophaga), fleas (Siphonaptera), mites, ticks, and chiggers (Acarina). Philander species are also a known reservoir for Trapanosoma cruzi , which causes trypanosomiasis in humans and animals.

In addition, since Philander species consume fruits, are mostly terrestrial, and move often, they are potential dispersers of seeds. One study by Medellin (1994) did find that the closely related Philander opossum does disperse seeds of Cecropia obtusifolia , a tree species important in succession of forests, into adequate germination sites such as light gaps, which other arboreal frugivores do not reach.

Economic Importance for Humans: Positive

It is unlikely that this species is of any positive economic importance for humans.

Economic Importance for Humans: Negative

Philander frenatus is unlikely to have a negative economic impact, but Philander species are a known reservoir for Trapanosoma cruzi , which causes trypanosomiasis in humans and animals.

Conservation Status

Philander frenatus is considered a species of least concern by IUCN Red List because of its wide distribution, expected large population size, and tolerance of human disturbance. The population size of P. frenatus is not known to be decreasing, but little is known about this population in general.

Other Comments

All species in the genus Philander were long considered subspecies of Philander opossum , including Philander frenatus . Thus, most older information is classified under P. opposum .

Additional Links

Encyclopedia of Life

Contributors

Rachel Cable (author), Animal Diversity Web Staff.

References

Ceotto, P., R. Finotti, R. Santori, R. Cerqueira. 2009. DIET VARIATION OF THE MARSUPIALS Didelphis aurita AND Philander frenatus (DIDELPHIMORPHIA, DIDELPHIDAE) IN A RURAL AREA OF RIO DE JANEIRO STATE, BRAZIL. Mastozoología Neotropical , 16: 49-68.

Chemisquy, M., D. Flores. 2012. Taxonomy of the southernmost populations of Philander (Didelphimorphia, Didelphidae), with implications for the systematics of the genus. Zootaxa , 3481: 60-72.

Costa, L., D. Brito, N. de la Sancha, D. Flores. 2011. " Philander frenatus " (On-line). IUCN 2012: The IUCN Red List of Threatened Species. Accessed April 02, 2013 at www.iucnredlist.org .

Cunha, A., M. Vieira. 2002. Support diameter, incline, and vertical movements of four didelphid marsupials in the Atlantic forest of Brazil. Journal of Zoology London , 258: 419-426.

Cáceras, N. 2004. Diet of three didelphid marsupials (Mammalia, Didelphimorphia) in southern Brazil. Mammalian Biology , 69/6: 430-433.

Davis, D. 1947. Notes on the life histories of some Brazilian mammals. Boletim do Museu Nacional , 76: 1-8.

Delciellos, A., M. Vieira. 2009. JUMPING ABILITY IN THE ARBOREAL LOCOMOTION OF DIDELPHID MARSUPIALS. Mastozoología Neotropical , 16/2: 299-307.

Flores, D., R. Barquez, M. Díaz. 2008. A new species of Philander Brisson, 1762 (Didelphimorphia, Didelphidae). Mammalian Biology , 73: 14-24.

Forero-Medina, G., M. Vieria. 2009. Perception of a fragmented landscape by neotropical marsupials: effects of body mass and environmental variables. Journal of Tropical Ecology , 25/1: 53-62.

Gentile, R., P. D'Andrea, R. Cerqueira, L. Maroja. 2010. Population dynamics and reproduction of marsupials and rodents in a Brazilian rural area: a five-year study. Studies on Neotropical Fauna and Environment , 35/1: 1-9.

Gentile, R., R. Finotti, V. Rademaker, R. Cerqueira. 2004. Population dynamics of four marsupials and its relation to resource production in the Atlantic forest in southeastern Brazil. Mammalia , 68: 109-119.

Hershkovitz, P. 1997. Composition of the family Didelphidae Gray, 1821 (Didelphoidea: Marsupalia), with a review of the morphology and behavior of the included four-eyed pouched opossums of the genus Philander Tiedmann, 1808. Fieldiana: Zoology , 86: 1-103.

Hingst, E., P. D'Andrea, R. Santori, R. Cerqueira. 1998. Breeding of Philander frenata (Didelphimorphia, Didelphidae) in captivity. Laboratory Animals , 32: 434-438.

Lira, P., F. Fernandez. 2009. A comparison of trapping- and radiotelemetry-based estimates of home range of the neotropical opossum Philander frenatus . Mammalian Biology , 74: 1-8.

Macedo, L., F. Fernandez, J. Nessimian. 2010. Feeding ecology of the marsupial Philander frenatus in a fragmented landscape in Southeastern Brazil. Mammalian Biology , 75: 363-369.

Medellín, R. 1994. Seed Dispersal of Cecropia obtusifolia by Two Species of Opossums in the Selva Lacandona, Chiapas, Mexico. Biotropica , 26/4: 400-407.

Moura, M., A. Caparelli, S. Freitas, M. Vieira. 2005. Scale-dependent habitat selection in three didelphid marsupials using the spool-and-line technique in the Atlantic forest of Brazil. Journal of Tropical Ecology , 21: 337-342.

Nowak, R. 2005. Walker's Marsupials of the World . Baltimore: The Johns Hopkins University Press.

Patton, J., M. da Silva. 1997. Definition of species of pouched four-eyed opossums (Didelphidae, Philander ). Journal of Mammalogy , 78/1: 90-102.

Patton, J., M. da Silva. 2007. Genus Philander Brisson, 1762. Pp. 27-35 in Mammals of South America . Chicago: The University of Chicago Press.

Pires, A., P. Lira, F. Fernandez, G. Schittini, L. Oliviera. 2002. Frequency of movements of small mammals among Atlantic Coastal Forest fragments in Brazil. Biological Conservation , 108: 229-237.

Voss, R. 2013. Opossums (Mammalia: Didelphidae) in the diets of Neotropical pitvipers (Serpentes: Crotalinae): Evidence for alternative coevolutionary outcomes?. Toxicon , 66: 1-6.