Common mole-rat

"African Mole Rat" redirects here. For other African species of mole rats, see Blesmol and Tachyoryctes.
Common mole-rat
Cryptomys hottentotus
Conservation status

Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Bathyergidae
Genus: Cryptomys
Species: C. hottentotus
Binomial name
Cryptomys hottentotus
(Lesson, 1826)

The Common mole-rat (Cryptomys hottentotus) is a burrowing rodent found in Southern Africa, in particular in the Western Cape province of South Africa. It also occurs in Lesotho, Malawi, Mozambique, Swaziland, Tanzania, Zambia, and Zimbabwe.[1] Cryptomys hottentotus is a species in the subfamily Bathyerginae.[2]

Physical appearance

Typically the body of a mature specimen of Cryptomys hottentotus may be as short as 10.5 to as long as 16.5 cm; the tail may be 1.2 to 3.8 cm. The fur is thick and evenly colored, usually grey or brown. In some specimens there is white spot on the head. The shape of the body is cylindrical with short appendages. Common mole rats have ungrooved chisel-like incisors that are used for digging as well as for feeding and fighting.[3]

Reproduction and development

Common mole-rats form colonies, essentially family groups with the largest female and male being the only reproductive pair. Mating begins in September and October.[1] During courtship the female raises her tail and allows the mate to smell her genital region. The male then gently chews on her hind region, mounts and mates. The birth of offspring is restricted to the southern hemisphere summer, during which there may be one or two litters of up to five pups. The gestation period is about 81 days.[1] The average age at reproductive maturity is about 450 days. Females maintain reproductive function during non-reproductive months.[2]

Ecology

Common mole-rats are fossorial and can live in a wide range of substrates.[1] They are herbivorous, mainly eating geophytes (plants with underground storage organs) and grass rhizomes. Common mole-rats are very widespread, thus their abundance is not well known. This species shows signs of localization due to soil requirements. The pattern of burrowing systems for common mole-rats optimizes their access to food, especially gephytes.[4] Burrowing has a negative economic impact in that it damages human property but it is also positive in that it improves soil drainage and turnover.[3]

Physiological attributes

Common mole-rats are endothermic, having the ability to generate their own heat and keep their body temperature above ambient temperature. In arid environments they have lower individual body masses; this reduces their need for food and improves energy conservation.[5]

These mole-rats also have long sensory hairs called vibrissae that stand out from the pelage (fur covering) over their body and hind legs.

Behavior

Common mole-rats live in family units of up to 14 individuals. They are eusocial in that colony members are specialized for functions such as reproduction and for cooperative care of the young. Younger mole-rats would likely be workers and older mole-rats could be casual workers. These workers, for the most part, burrow and forage, with casual workers not working as much as younger workers. The oldest mole rats are breeders.[3]

Tunneling

Mole-rats have cylindrical bodies with short limbs adapted to activities inside their tunnels. Their loose skins and dense fur assist in negotiating small spaces. They can practically somersault within their loose skins. Their hairy cheeks can close behind the incisors to keep dirt and soil from the throat while they dig. In digging they loosen soil with the incisors, then use their feet to pass the loosened soil back beneath the body. When the mole-rat has accumulated a suitable batch of loose earth, it reverses to push the soil out of the tunnel.

Conservation

The IUCN Red List lists Cryptomys hottentotus as of Least Concern.[1] Because of their dense and widespread population and their adaptability to pasturelands and rural gardens, their prognosis is a positive one.

References

Wikispecies has information related to: Cryptomys hottentotus
Wikimedia Commons has media related to Cryptomys hottentotus.
  1. 1.0 1.1 1.2 1.3 1.4 1.5 Maree, S.; Faulkes, C. "The IUCN Red List of Threatened Species". Version 2009.1. Retrieved 2009-08-24. |chapter= ignored (help)
  2. 2.0 2.1 Bishop, J.M.; Jarvis, J.U.; Spinks, A.C.; Bennett, N.C.; O'Ryan, C. (2004). "Molecular insight into patterns of colony composition and paternity in the common-mole rat Cryptomys hottentotus hottentotus". Molecular Ecology 13 (5): 1217–1229. doi:10.1111/j.1365-294X.2004.02131.x. PMID 15078457.
  3. 3.0 3.1 3.2 Bruening, S. (2001). "Cryptomys hottentotus: African mole rat". Retrieved 2008-11-23.
  4. Spinks, A.C.; Bennett, N.C.; Jarvis, J.U.M. (1998). "Regulation of Reproduction in female Common-mole rats (Cryptomys hottentotus hottentotus): The effects of breeding season and reproductive status". Journal of Zoology 268: 161–168. doi:10.1017/s0952836999006032.
  5. Spinks, A.C.; Bennett, N.C.; Jarvis, J.U.M. (2000). "A comparison of the ecology of two populations of the common mole-rat, Cryptomys hottentotus hottentotus: The effect of aridity on food, foraging and body mass". Oecologia 125 (3): 341–349. doi:10.1007/s004420000460.
  1. Woods, C.A.; Kilpatrick, C.W. (2005). "Cryptomys hottentotus". In D.E. Wilson & D.M. Reeder (Eds.), Mammal species of the world: A taxonomic and geographic reference (3rd Ed.), pp 1538–1600. Smithsonian Institution Press: Washington, D.C. The encyclopedia of mammals Page 690-693