Caluromys lanatus, the western or brown eared woolly opossum, is a South American opossum species. Its distribution ranges east of the Corillera Central and Andes mountain ranges in Colombia, northwestern and southern Venezuela, eastern Ecuador, eastern Peru, northern Bolivia, eastern Paraguay, northern Argentina, and western Brazil. (Allen, 2007; Emmons and Feer, 1997)
There are six recognized subspecies of C. lanatus, each distinguished by its range. Caluromys lanatus cicur is found in northeastern Colombia and northwestern Venezuela. Caluromys lanatus lanatus is found in Paraguay, provincia Misiones in Argentina, and the state of Rio Grande do Sul in southern Brazil. Caluromys lanatus nattereri is found in the Mato Grosso and Mato Grosso do Sul states of southwestern Brazil and adjacent Bolivia. Caluromys lanatus ochropus is found in southern Venezuela and western Brazil. Caluromys lanatus ornatus is found in southern Colombia and east of the Andes in Ecuador, Peru, and Bolivia. Caluromys lanatus vitalinus is found in southeastern Brazil. (Allen, 2007)
Caluromys lanatus resides in lowland humid forests between 200 and 1300 m in altitude, more commonly below 500 m. It is mostly found near streams or other moist areas, but also occupies drier areas. Although it prefers dense, primary, midstory and canopy forests with vines and epiphytes, it can also be found in open forests, mature and secondary evergreen rainforest, forest that has been disturbed, gallery forest, and even gardens and plantations. Caluromys lanatus uses the middle and upper strata of trees in these environments, so it is typically caught in traps 5-15 m above ground. In Brazil, C. lanatus can be found in both terra firme and várzea forests. (Allen, 2007; Emmons and Feer, 1997; Handley Jr., 1976; Lambert, et al., 2005; Patton, et al., 2000; Tirira, 2007)
Caluromys lanatus is a medium-sized, slender opossum with a broad head and pointed snout. Its head and body length is 201-319 mm, tail length is 330-435 mm, and weight is 290-410 g. It has long, dense, woolly hair that is reddish-brown to pale brown on the dorsum and sides, and yellowish white on the venter, sometimes with gray in the center. The reddish color is darker on the shoulders, forearms, and hind legs. The face of C. lanatus is gray with a dark stripe down the center, reddish brown eye rings around large brown eyes, and large, naked, brownish ears. The feet are reddish brown to dark gray in color. Its tail is prehensile, with thick fur up to 50% from the base on the dorsum and up to 20% on the venter. The remainder of the tail is naked, with a portion of the skin spotted with brown spots. Females develop pouches only when carrying young. (Emmons and Feer, 1997; Linares, 1998; Tirira, 2007)
Some subspecies of Caluromys lanatus differ in their physical appearance. Caluromys lanatus cicur has a grayish-brown dorsum, gray sides, and can have a completely gray venter. Caluromys lanatus lanatus has pale brown fur and lacks any pigmented spots on the tail. Caluromys lanatus ochropus has a distinct red-brown dorsum, and is larger than nearby C. l. lanatus. (Cáceres and Carmignotto, 2006; Emmons and Feer, 1997)
The range of Caluromys lanatus overlaps with several species similar in appearance. However, Caluromysiops irrupta has black shoulders and a tail furred all the way to the tip, Glironia venusta has two dark stripes on the head instead of one and a tail furred all the way to the tip, species in the genus Micoureus have no dark stripe on their heads and tails furred only by the base, and Caluromys philander has a tail only furred near the base. (Emmons and Feer, 1997)
Caluromys lanatus most likely breeds year-round, as pouched young and postlactating females have been caught throughout the year, and females cycle throughout the year. Litter sizes are small, with 1-2 young in the Amazon Basin and 3-4 young in southern portions of the range. They reach sexual maturity at the age of 7-8 months. The length of estrus for females is 20-31 days, and females can have up to three litters in one year. The average body mass of young averaged 3.5 g in a seasonal forest in Brazil. (Bucher and Fritz, 1977; Cáceres and Carmignotto, 2006; Linares, 1998; Patton, et al., 2000)
Little else seems to be known about reproduction in this species, but other opossums with known reproductive behavior give birth to highly altricial young that are nursed by the female for at least several weeks and probably remain at least partially dependent on maternal care of some sort for at least another month.
As far as known all female opossums nurse newborn young, groom them, and presumably protect them from predators for at least several weeks postpartum. Paternal care has not been reported for any opossum species.
Caluromys lanatus is a nocturnal, arboreal species that is solitary. It spends the daylight hours in hollow trees, where it may also build its nest. It moves slowly and quietly during the night, slowly approaching and capturing insects with its hands. It is also a curious species that will approach human encampments, perhaps to prey upon the insects that are attracted to lights. It will react aggressively when caught and handled. (Bucher and Fritz, 1977; Emmons and Feer, 1997; Linares, 1998; Tirira, 2007)
Caluromys lanatus makes few sounds, but will make clicking sounds during mating and hissing sounds when threatened. 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. (Linares, 1998; Tirira, 2007)
Caluromys lanatus is an omnivore. It primarily eats fruits (80-85% of diet), but also consumes soft vegetables, insects, other invertebrates, small vertebrates (15-20% of diet). It will also drink flower nectar in the dry season and the gum and sap from the bark of certain trees. One study performed by Casella and Cáceras (2006) in southern Brazil found that all trapped C. lanatus individuals ate fruits, including those of the species Cecropia pachystachia, Cyphomandra sp., Ficus luschnatiana, Piper sp., and species in the family Solanaceae. All individuals also ate invertebrates in the orders Coleoptera and Hymenoptera. In addition, 40% of individuals consumed birds, 60% consumed mammals, and 40% consumed unidentified plant parts. (Casella and Cáceras, 2006; Emmons and Feer, 1997; Linares, 1998; Tirira, 2007)
Little is known about what preys upon C. lanatus, but the closely related Caluromys derbianus and Caluromys philander have been found in the stomach contents of the pitvipers Bothrops asper and Bothrops jararaca. Besides snakes, other predators likely include owls and wild felids. (Voss, 2013)
Since Caluromys lanatus is a mobile opossum that consumes flower nectar in the dry season, it is a potential pollinator for these flowering species. Such plant species include Quararibea cordata and Pseudobombax tomentosum. Caluromys lanatus individuals have also been found to carry Trapanosoma cruzi and Ablyomma nymphs in Brazil, Colombia, and Peru. Additional 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). (Cáceres and Carmignotto, 2006; Gribel, 1988; Janson, et al., 1981)
Caluromys lanatus was formerly hunted for its fur, but the fur is no longer in demand, so hunting by humans has most likely been reduced. The Yekuana and Yanomami people in the Amazon will occasionally trap C. lanatus individuals as pets for children. (Emmons and Feer, 1997; Linares, 1998)
Caluromys lanatus is considered a species of least concern by IUCN Red List because it has a wide distribution, a presumably large population, and occurs in protected areas throughout its range. Deforestation may be a threat for some populations, as it is an arboreal species. (Costa, et al., 2008; Linares, 1998)
Rachel Cable (author), Animal Diversity Web Staff.
living in the southern part of the New World. In other words, Central and South America.
uses sound to communicate
living in landscapes dominated by human agriculture.
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.
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
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.
parental care is carried out by females
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
an animal that mainly eats fruit
An animal that eats mainly plants or parts of plants.
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.
the area in which the animal is naturally found, the region in which it is endemic.
an animal that mainly eats nectar from flowers
active during the night
an animal that mainly eats all kinds of things, including plants and animals
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
uses touch to communicate
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
breeding takes place throughout the year
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