Ctenomys fulvustawny tuco-tuco

Geographic Range

This species of Tuco-tuco inhabits northern Argentina and northern Chile.


Ctenomys fulvus lives in areas of sandy soils at reasonably high elevations. They are associated with desert flats with Larrea or other low shrubs and riparian forests along dry gullies.

Physical Description

In general, Tuco-tucos grow to a length of about 8 to 14 inches (20-36 cm)including a long tail. The body is robust and cylindrical and their head is large. They have long front teeth, large heads, muscular limbs, and powerful digging claws. The forelimbs are somewhat shorter than the hind limbs and the claws on the forefeet are the longest. The hind feet of the Tuco-tuco possess stiff fringes of bristle like hair. They use these bristles to groom dirt from their hair. The tail of Ctenomys fulvis is greater than 45% of the length of it's head and body combined. Their eyes are small and they have reduced external ears.

Most tuco-tucos have brown to grayish fur. This species can be identified by its pale and uniformly buffy pelage (sometimes mixed with blackish). Its tail is bicolored and may have a small tuft of fur at the end.

The dental formula of all Tuco-tucos is 1/1,0/0,1/1,3/3

They have thick large front incisors that have a bright orange enamel.

  • Range mass
    0.300 to 0.400 kg
    0.66 to 0.88 lb
  • Average mass
    0.360 kg
    0.79 lb
  • Range length
    296 to 341 mm
    11.65 to 13.43 in
  • Average length
    317 mm
    12.48 in


In general, females usually produce only a single litter per year. Females are typically monestrus, but may experience a postpartum estrus. No information was found for this species.

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


These tuco-tucos live in large colonies that can extend up to seventeen acres. Each burrow is typically inhabited by only one Tuco-tuco.

The digging of the burrows occurs mostly during daylight hours. This animal rarely leaves its burrow and if it does it only comes out for a brief period of time.

Communication and Perception

Food Habits

Ctenomys fulvus feeds on roots and underground plant parts.

  • Primary Diet
  • herbivore
    • eats sap or other plant foods
  • Plant Foods
  • roots and tubers


Enemies of Ctenomys fulvus include owls, falcons, or other birds of prey. Most tuco-tucos use a loud clicking noise to warn against predators.

Economic Importance for Humans: Negative

Tuco-tucos have been known to damage cultivated crops and compete with livestock for food.

Conservation Status


Shelly Charron (author), University of Michigan-Ann Arbor, Bret Weinstein (editor), University of Michigan-Ann Arbor.



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

World Map

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


used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.


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.


An animal that eats mainly plants or parts of plants.


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.

scrub forest

scrub forests develop in areas that experience dry seasons.


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


associates with others of its species; forms social groups.


uses touch to communicate


that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).


""Tuco-tuco," Discovery Channel School, original context provided by Worldbook Online" (On-line). Accessed 11/19/01 at www.discoveryschool.com/homeworkhelp/worldbook/atozscience/t/748847.html.

"Mammal Image Library Catalog" (On-line). Accessed 11/19/2001 at www.emporia.edu/biosci/msl/rodent/htm.

Diaz, M., J. Braun. 1999. Key to the Mammals of Catamarca Province Argentina. Occasional Papers of the Oklahome Museum of Natural History, Number 4, August 1999: 1-16.

Mares, M. 1976. Convergent Evolution of Desert Rodents: Mulivariate Analysis and Zoogeographic Implications. Paleobiology, Vol. 2: 39-63.

Mares, M. 1975. South American Mammal Zoogeography: Evidence from Convergent Evolution in Desert Rodents. Procedings of the National Academy of Sciences of The United States of America, Vol. 72: 1702-1706.

Nowak, R. 1997. "Walkers Mammals of the World Online" (On-line). Accessed 11/15/01 at www.press.jhu.edu/books/walker/w-index.html.

Redford, K., J. Eisenberg. 1992. Mammals of the Neotropics, the Southern Cone. Chicago: University of Chicago Press.