Salpingotus crassicaudathick-tailed pygmy jerboa

Geographic Range

Salpingotus crassicauda is found in northwest China, Southwest Mongolia, and the Soviet Union.

Habitat

Salpingotus crassicauda can be found in steppes and deserts. They dig burrows in sand dunes. Their burrows can extend up to three meters in length (Holden 1993, Nowak 1991).

Physical Description

Head and body range in length from 41 to 47 mm. The tail is more than double the length of the body, ranging in length from 93 to 126 mm. The tail is swollen at the proximal end, due to fat storage, and it is covered with short hairs that become longer toward the terminal end. The metatarsals are extended and range from 20 to 25 mm. There are only three toes present in each hind foot of S. crassicauda. It has tufts of hair beneath each toe, which aid in gripping when running on soft sand. S. crassicauda has external ears that are small and round (MacDonald 1984, Nowak 1991, Ognev 1963).

Reproduction

Salpingotus crassicauda females have eight teats and have an average litter of 2.7 young. Sexual maturity is not reached in the first year. The reproductive behavior is unknown. Other northern species of jerboas, however, breed shortly after emerging from hibernation. These jerboas are thought to have two litters per season consisting of two to six young (Nowak 1991, MacDonald 1984, Ognev 1963).

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

Behavior

No specific information was available for S. crassicauda, the following is from a general account of jerboas. Jerboas are generally quiet, although some species tap with their hind foot. They move about walking on their hind legs. Their forelimbs are used for gathering food. Jerboas also move using all four limbs when hopping or jumping to escape predators. Some jerboas hibernate through the winter and some enter torpor during hot or dry periods. This may explain the large store of fat in the tail of S. crassicauda (MacDonald 1984).

Communication and Perception

Food Habits

Salpingotus crassicauda feeds on insects and vegetable matter. However, in captivity one Salpingotus ate only invertebrates. S. crassicauda may also eat seeds, like many other jerboas (Nowak 1991, MacDonald 1984).

Economic Importance for Humans: Negative

Jerboas in general may be a pest to melon growers, however, there were no reports of this behavior specifically for this species (MacDonald 1984).

Conservation Status

Salpingotus crassicauda is regarded as rare in both China and the Soviet Union (Nowak 1991).

Other Comments

There are other sources of information available on Salpingotus crassicauda, however, many of these are written in either Russian or German. Holden (1993) noted that some populations of S. crassicauda found south of Lake Balkhash and north of Aral Sea have recently been reclassified as a separate species, S. Pallidus.

Contributors

Stephanie Bunker (author), University of Michigan-Ann Arbor.

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

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.

chemical

uses smells or other chemicals to communicate

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.

endothermic

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.

motile

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.

sexual

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

tactile

uses touch to communicate

References

Holden, M. E. 1993. Mammal Species of the World. Second Edition. Smithsonian Institution Press, Washington and London.

MacDonald, D. 1984. Encyclopedia of Mammals. Facts on File Publications, New York.

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

Ognev, S. I. 1963. Mammals of the USSR and Adjacent Countries. Vol. VI. Israel Program for Scientific Translation Ltd., Jerusalem.