The red rock rat, or red veld rat, (''Aethomys chrysophilus'') is a species of
rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are n ...
murine
The Old World rats and mice, part of the subfamily Murinae in the family Muridae, comprise at least 519 species. Members of this subfamily are called murines. In terms of species richness, this subfamily is larger than all mammal families ex ...
rodent. Adults have a head-body length of , with a long, , tail, and weigh from . Males are not significantly larger than females. The fur on the upper body and flanks is mostly reddish-brown, but mixed with dark brown or black hairs, producing an overall colour that varies from orange-yellow or cinnamon to medium brown. The underparts are white or very pale grey, with a clear dividing line from the fur elsewhere on the body. The head is robust, with a heavy snout. Females have three pairs of
teat
A teat is the projection from the mammary glands of mammals from which milk flows or is ejected for the purpose of feeding young. In many mammals the teat projects from the udder. The number of teats varies by mammalian species and often corr ...
s.
Although red rock rats can be distinguished from most other species of the genus ''
Aethomys
''Aethomys'' is a genus of rodent from Africa.CHIMIMBA, CHRISTIAN T., NICO J. DIPPENAAR, and TERENCE J. ROBINSON.Morphometric and morphological delineation of southern African species of Aethomys (Rodentia: Muridae)" Biological Journal of the Li ...
'' by their size or bodily proportions, they appear essentially identical to Tete veld rats, and can only be reliably distinguished from them by genetic analysis or examination of the shape of their
spermatozoa
A spermatozoon (; also spelled spermatozoön; ; ) is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote. (A zygote is a single cell, with a complete set of chromos ...
.
Distribution and habitat
Red rock rats are widely distributed across southern Africa, although the exact southern edge of their range is difficult to determine because of their extreme physical similarity to Tete veld rats, which are found in
South Africa
South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...
and Eswatini. Nonetheless, red rock rats are currently believed to live in east Africa from southern
Kenya
)
, national_anthem = " Ee Mungu Nguvu Yetu"()
, image_map =
, map_caption =
, image_map2 =
, capital = Nairobi
, coordinates =
, largest_city = Nairobi
...
, through eastern
Tanzania
Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands ...
,
Malawi
Malawi (; or aláwi Tumbuka: ''Malaŵi''), officially the Republic of Malawi, is a landlocked country in Southeastern Africa that was formerly known as Nyasaland. It is bordered by Zambia to the west, Tanzania to the north and northeas ...
,
Mozambique
Mozambique (), officially the Republic of Mozambique ( pt, Moçambique or , ; ny, Mozambiki; sw, Msumbiji; ts, Muzambhiki), is a country located in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi ...
, and
Zimbabwe
Zimbabwe (), officially the Republic of Zimbabwe, is a landlocked country located in Southeast Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa to the south, Botswana to the south-west, Zambia to the north, and ...
to the north-eastern border regions of South Africa. Further west, they are found through most of
Zambia
Zambia (), officially the Republic of Zambia, is a landlocked country at the crossroads of Central, Southern and East Africa, although it is typically referred to as being in Southern Africa at its most central point. Its neighbours are t ...
and
Botswana
Botswana (, ), officially the Republic of Botswana ( tn, Lefatshe la Botswana, label= Setswana, ), is a landlocked country in Southern Africa. Botswana is topographically flat, with approximately 70 percent of its territory being the Kalaha ...
to northern
Namibia
Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa. Its western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south and ea ...
.
Across this region, red rock rats inhabit savannah or woodland areas with dense vegetation or rocky cover below elevation. They are often associated with
miombo
The Miombo woodland is a tropical and subtropical grasslands, savannas, and shrublands biome (in the World Wide Fund for Nature scheme) located primarily in Central Africa. It includes four woodland savanna ecoregions (listed below) characterized b ...
and
mopane
''Colophospermum mopane'', commonly called mopane, mopani, balsam tree, butterfly tree, or turpentine tree, is a tree in the legume family (Fabaceae), that grows in hot, dry, low-lying areas, in elevation, in the far northern parts of southern A ...
forest, but appear able to tolerate a wide range of habitats, so long as substantial ground cover is available.
Although at least seven subspecies of red rock rats have been identified, the validity of some of these is questionable, not least because of potential confusion with Tete veld rats in earlier works. Fossils indistinguishable from the modern species have been found which are dated as far back as 3.7 million years ago, in the late
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58nocturnal and
omnivorous
An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nut ...
, but feed mainly on plant matter, such as seeds, fruit, green leaves, and starchy roots. They shelter through the day in cup-like nests constructed in burrows, rock crevices, or
termite
Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blatto ...
mounds. In the wild, they appear territorial, reacting aggressively to intruders of their own species, but they are apparently able to tolerate each other after some time in captivity, establishing a stable dominance hierarchy.
Within any given area, red rock rats are usually present in relatively low numbers, but their population turns over rapidly, increasing rapidly during the wet season, with population densities reaching up to , then crashing to or less in the hot, dry, season.
In the wild, they breed during the rainy season, typically between October and January, although they are capable of breeding at any time of year in captivity. Gestation lasts 29 days, and results in the birth of between one and five, but typically three, young. The young are initially blind and helpless, with thin black fur over most of the body, and naked undersides. The teeth are already erupted at birth, and the eyes open after 10 to 14 days. Newborn young weigh only around , and measure in head-body length, but they grow rapidly, being weaned between 24 and 33 days, by which time they have already attained the adult coat and general appearance.
The young attain the full adult dimensions at around seven weeks, although they may still be somewhat lighter than fully grown adults at this point. They reach sexual maturity at around 82 days, but may not give birth to their first litter for up to six months.