Ototylomys phyllotisbig-eared climbing rat

Geographic Range

Ototylomys phyllotis is found from the Yucatan Peninsula of southeastern Mexico to central Costa Rica. Nowak (1991) Lawlor (1982)


Ototylomys is found in tropical forests, both dry and wet, with abundant rocks or rocky ledges. Lawlor (1982) Nowak (1991)

Physical Description

Head and body length is 95 - 190 mm and tail length usually falls between 100 - 190 mm. The body is bicolored, with a gray/brown coloration dorsally and a white/gray coloration ventrally. Hands and feet are pale. The tail is long, predominantly hairless, covered in large scales, and can be anywhere from a dark, dull gray/brown to black, with a paler coloration on the ventral surface. The eyes and ears are large and the ears are hairless. Adults and juveniles show two distinct pelage patterns. Lawlor (1982) Nowak (1991)


There appears to be no specific time for breeding in Ototylomys. Average gestation period is 52 days, although caged specimens have shown periods of up to 174 days, due presumably to delayed implantation. The average of 52 days is the longest known gestation period in myomorphous rodents. This long gestation allows for highly precocial young, and foraging of young has been observed 11 days after their birth. Sexual maturity may be reached as early as 30 days after birth. Litter size ranges from 1 to 4. Lawlor (1982) Nowak (1991)

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual


The species is nocturnal and arboreal. Activity is primarily on low creepers and branches, although specimens have been observed foraging on the ground and among rocks. It is believed that individuals maintain a home range that also contains vertical components. Ototylomys is not a social species and most social interaction occurs during mating. Lackey (1989) Lawlor (1982) Nowak (1991)

Communication and Perception

Food Habits

Ototylomys forages both on the ground and in trees. As it is found primarily in tropical areas, a wide variety of food sources are exploitable, with fruits and leaves being favored. Lawlor (1982) Nowak (1991)

Conservation Status

There is only one species in the genus Ototylomys.


Mike Kuznetz (author), University of Michigan-Ann Arbor.


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.


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.


forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.


having the capacity to move from one place to another.


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


Lackey, J.A. "Notes on the biology of the big-eared climbing rat, Ototylomys phyllotis, on the Yucatan Peninsula, Mexico." Texas Journal of Science 41(3)253-264, 1989.

Lawlor, T.E. "Ototylomys phyllotis." Mammalian Species 181: 1-3, 1982.

Nowak, R.M. 1991. Walker's Mammals of the World. Fifth Edition, vol. 2. Johns Hopkins University Press: Baltimore.