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The striped polecat ( Ictonyx striatus), also called the African polecat, zoril, zorille, zorilla, African muishond, striped muishond, Cape polecat, and African skunk, is a species of mammal native to sub-Saharan Africa. Despite bearing some resemblance to a skunk (of the family Mephitidae), it actually belongs in a separate family known as the Mustelidae, and genetic analysis suggests that its closest living relative is the African striped weasel. Historically, this species has been wrongly classified as a type of skunk or sloth. It is adaptable and lives in a wide range of habitats and elevations, with a preference for open environments that have lower levels of shrubs, especially ones where large are present to control shrub growth. It avoids dense rainforests and deserts with no scrub cover, thus being absent from the Congo Basin, the more coastal areas of West Africa, and the driest parts of Somalia and Ethiopia.
Measuring in length excluding the tail, the striped polecat is a small mammal, with males growing larger than females. Its fur is mostly black, with distinctive white stripes running down its back and white patches on its face and tail, though the exact patterning is highly variable between different individuals and populations. A large number of subspecies have been proposed based on these differences, though it is unclear how many of these (if any) are valid. Near its anus, the striped polecat has glands which can spray a nauseating, irritating fluid at potential predators as a way of defending itself. Its striking colouration is an example of aposematism, warning predators of its spray to deter them from attacking, and it takes a defensive stance with its back arched and tail raised before it sprays. Feigning death is another method it uses to avoid predation.
The forelimbs of this animal bear long, curved claws which it uses to excavate or dig for invertebrate prey in soil or dung. The striped polecat is a predatory and mostly carnivorous animal that primarily feeds on insects, and small , catching them on the ground or just beneath the surface. Birds, eggs, and other invertebrates are also known prey items. A nocturnal creature, it actively forages throughout the night and retreats to a resting area during the day, which is typically a burrow or other crevice. Most prey is eaten whole and killed with a bite to the head, sometimes while pinned down using the mustelid's forelimbs, though larger prey may bitten in other areas and skinned before they are eaten. Plant matter may also be consumed, though this is much more rarely eaten than animal prey. Due to its defensive spray, the striped polecat is rarely targeted by predators, and vehicular collision is a more common cause of death. Multiple parasite species may occur in or on this mammal, and it is also a known carrier of rabies.
The striped polecat is a mostly solitary animal, and adult males are hostile towards one another, though family groups do occur and multiple can be kept together in captivity. Females tolerate males during the breeding season, and after a gestation period of 36 days, the mother gives birth to and raises her litter of two or three young. Newborns have closed eyes and ears, and are almost hairless, with most of their pink skin visible. A variety of different calls are used by striped polecats to communicate with each other, as are behavioural cues such as raised hair when angered or displaying their black underside in friendly interactions. Olfactic communication involving its odorous fluids likely occurs as well. Though it may compete with other small carnivores in its range such as , genets and African striped weasels, this is likely minimized by niche partitioning. The striped polecat is common across most of its range, despite localized population declines, and is not believed to face any major threats to its overall survival as a species.
This species is referred to by a wide range of vernacular names, one of the most common being "striped polecat". The English word polecat combines the English word cat with the Middle French word poul or pol (meaning "cock"). This word was originally used for the European polecat, referencing its predation on poultry. Another commonly used name is zorilla, sometimes spelled as zorille, which comes from the Spanish word zorillo (meaning "skunk"), itself a diminutive form of the Spanish zorro (meaning "fox"). The names "African skunk", "African muishond" and "striped muishond" have also been used, though the former is inaccurate since this animal belongs in a separate family from true skunks. Muishond is an Afrikaans word derived from the Middle Dutch term muushont, meaning "mouse hound", and is also used in reference to various mongoose species.
More specimens of striped polecats would be analyzed throughout the 19th century, with various authors establishing new species names based on them. They have since been found to represent the same species and the taxa erected based on them are thus considered synonymous. British zoologist Andrew Smith wrote a catalog in 1826 of the mammal specimens in the South African Museum. He believed one specimen represented an unknown species of skunk in the genus Mephitis, and gave it the scientific name Mephitis capensis. Later in 1829, German zoologist Johann Baptist Fischer described a species under the name Mustela zorilla based on specimens from Senegal and the Cape of Good Hope, South Africa, recognizing that it belongs in the family Mustelidae. This species was moved to the genus Putorius by Smith in 1834, renaming it as Putorius zorilla. The genus Ictonyx was established by German naturalist Johann Jakob Kaup in 1835 to contain a single species, which was given the name Ictonyx capensis, marking the first time the striped polecat was assigned to a newly established genus rather than one which already existed. Kaup described the species based on specimens from the Cape of Good Hope, South Africa, which is referenced in the specific name. The name Mephitis africana was erected for the striped polecat by German explorer Hinrich Lichtenstein in 1836, who believed like Smith that it is a species of skunk. However, along with Mustela zorilla, this name was synonymized in 1841 with Rhabdogale mustelina, a taxon established by Johann Andreas Wagner that year.
During the early 1900s, the striped polecat was commonly referred to under the scientific name Zorilla striata, with experts such as Édouard Louis Trouessart and William Lutley Sclater using it in their publications. This name was first used in 1861 by Edgar Leopold Layard. However, it was pointed out by American zoologist Arthur H. Howell in 1906 that this name is invalid; the specific name striata originates from an 1800 publication by George Shaw but is based on Viverra putorius and thus refers to the eastern spotted skunk, while the generic name Zorilla is preoccupied as it was already used by Lorenz Oken in 1816. Howell determined that the proper specific name of the animal should be capensis, as he thought it was the oldest given to it (by Smith in 1826). He also concluded that its proper generic name should be Ictonyx since the animal does not belong in any of the other genera it was formerly placed in and requires its own genus, thus assigning it the binomial name Ictonyx capensis. In 1915, American biologist Ned Hollister realized that the "weasel sloth" described by Perry in 1810 is actually a striped polecat and thus likely originated from Africa rather than South America as formerly claimed. With this knowledge, striatus became the oldest valid specific name assigned to the striped polecat, giving it priority over capensis, and the animal's proper binomial name is therefore Ictonyx striatus.
| I. s. striatus (Nominate subspecies) | Perry, 1810 | Largely black, with four white back stripes, a white forehead spot and white patches beneath the ears. | Cape Province, South Africa |
| I. s. albescens | Heller, 1913 | White patterns on the back very extensive, with the black parts of the nape and shoulders reduced to thin stripes. | Summit of Mount Lololokwi, Kenya |
| I. s. arenarius | Roberts, 1924 | Smaller and has larger ears than the nominate subspecies, with broader and pure white stripes (instead of buffy white like some other subspecies). | Lambert's Bay, South Africa |
| I. s. elgonis | Granvik, 1924 | ||
| I. s. erythreae | de Winton, 1898 | Smaller than the nominate subspecies, with similar coloration to it, but the black dorsal stripes are narrower over the loins and the white patch under the mouth is more extensive in this subspecies. | Habr Heshi, Somaliland |
| I. s. ghansiensis | Roberts, 1932 | Similar to I. s. arenarius but with more white on the back due to the narrower black stripes, and a wider skull. | Gemsbok Pan, South Africa |
| I. s. giganteus | Roberts, 1932 | Much larger than I. s. kalaharicus, with clearly defined black dorsal stripes (though narrower than in the nominate subspecies), and the hind half of the tail is black. | Shorobe, Botswana |
| I. s. intermedius | Anderson and de Winton, 1902 | Smaller than I. s. senegalensis, white patterns on the frontal and in front of the ears commonly merge. | Lado, near Gondokoro, South Sudan |
| I. s. kalaharicus | Roberts, 1932 | The white dorsal stripes are very broad, reducing the black stripes to narrow lines over the shoulder, leaving them clearly visible only behind the shoulders. Hind half of the tail is black. | Kuke Pan, Central Kalahari, Botswana |
| I. s. lancasteri | Roberts, 1932 | Has broad black dorsal stripes, and unlike in other southern African subspecies the white dorsal stripes connect to the white frontal spot. | Choma, Zambia |
| I. s. limpopoensis | Roberts, 1917 | Has very defined back stripes and very little white on the tail (only at the tip) compared to the nominate subspecies, with a small and almost circular frontal spot. | Mooivlei, South Africa |
| I. s. maximus | Roberts, 1924 | Larger than the other South African subspecies, particularly in the skull and teeth, with creamy white stripes like the nominate subspecies. | Wakkerstroom, South Africa |
| I. s. obscuratus | de Beaux, 1924 | Similar to I. s. shoae in size and coloration, but with more white on the back (due to narrower black stripes) and shorter fur. | Luuq, Somalia |
| I. s. orangiae | Roberts, 1924 | Smaller than the nominate subspecies, with narrower white stripes and a discontinuous inner stripe broken in the middle of the back and on the rump. | Angra Pequina, south of Bothaville, South Africa |
| I. s. ovamboensis | Roberts, 1951 | Intermediate in size between I. s. kalaharicus and I. s. giganteus, but with smaller upper carnassial and molar teeth. Tail is largely black, and the black dorsal stripes are clearly defined. | Oshikango, Namibia |
| I. s. pretoriae | Roberts, 1924 | Similar to I. s. orangiae but with larger upper carnassial teeth and scantier fur on the underside. | Boekenhoutfontein, South Africa |
| I. s. senegalensis | Fischer, 1829 | White patterns wider than in the nominate subspecies. | Senegal |
| I. s. shoae | Thomas, 1906 | Slightly larger than the nominate subspecies, with a tail less white and a larger frontal spot. | Addis Ababa, Ethiopia |
| I. s. shortridgei | Roberts, 1932 | Very large subspecies, the black dorsal stripes are narrower in the front part of the body, tail is whiter than in the South African subspecies. | Maschi River at the border of the Caprivi Strip, Namibia |
The Saharan striped polecat is sometimes placed in the genus Ictonyx along with the striped polecat, whereas the African striped weasel is the only species assigned to the genus Poecilogale. Such placements would make Ictonyx a paraphyletic grouping, so some authors suggest placing the Saharan striped polecat in a genus called Poecilictis instead, making Ictonyx a monotypic genus containing only the striped polecat.
Fossilized remains of striped polecats have been discovered in several Pleistocene-aged localities in South Africa, such as Die Kelders Cave, Blombos Cave, and a fissure fill in Swartklip. Among the oldest specimens originate from the Sea Harvest Site in Saldanha Bay, and likely date back to a cooler phase of the Last Interglacial, between 128,000 and 74,000 years ago. An extinct species known from fossils found in Laetoli, Tanzania has been named Ictonyx harrisoni, and would have lived 3.85 to 3.63 million years ago during the Early Pliocene epoch. Though smaller than the striped polecat and differing in tooth structure, I. harrisoni is mostly similar to the extant animal and is therefore placed in the same genus. Another fossil species was formerly assigned to the genus Ictonyx and given the name Ictonyx bolti in 1985, as it was believed at the time that the striped polecat is its closest living relative. However, further analysis of its remains has shown that it is more closely related to the African striped weasel, so in 1987 this species was moved to its own separate genus named Propoecilogale.
The fur on the back of a striped polecat is silky and long, growing in length, while the fur on the head is shorter and only . The tail fur is particularly long, reaching , giving the tail a bushy appearance. All claws and digits touch the ground when the animal is walking, and their impressions can be seen in the footprints. Five digits are present on each of the four limbs, with each digit bearing a claw. The claws of the front limbs are longer and more curved than those of the hind limbs, with the former growing about while the latter tend to only measure . The front paws are larger than the hind paws, and the soles of all four paws are hairless. Each paw is narrow and most of the digits are spread wide apart, though the third and fourth digits of each hind paw are close together. Every digit has an oval-shaped pad, and each paw has a four-lobed pad forming a shape with a notch in the back, with each front paw having two additional carpal pads on the wrist area. All of these pads have coarse grooves.
The skull is heavily built, with a braincase that is wide at the back and becomes narrower towards the front, and a short, blunt snout. The palate is also wide in its hind portion, becoming narrower past where the molar teeth are. The eyes are located near the front of the head, with the distance between the front edges of the eye sockets and the tip of the maxilla being only a quarter the length of the entire skull. There is no sagittal crest in this species, though two low ridges serving as attachments for the temporalis muscles are visible from the supraoccipital crests (at the back of the skull) to the postorbital processes (behind the eye sockets). The auditory bullae (bony structures containing the middle and inner ears) are wide and flat, and the zygomatic arches (arch-like bones in the cheeks) are wider at their bases than at their centers. The dentition has a dental formula of , that is, three , one Canine tooth and three in each half of either jaw, with each half of the upper jaw having one molar while that of the lower jaw has two, giving a total of 34 teeth. The canines are short and robust, with the lower canines bending backwards at their tips, and the outer incisors of the upper jaw are longer than the inner incisors, being used alongside the canines to subdue prey. The molars have broad grinding surfaces, allowing the animal to crush food, especially insects.
The species walks with a gait similar to that of a skunk, with its back slightly arched and tail extending horizontally in line with the body while trotting slowly. Though capable of swimming and climbing trees, it tends to avoid doing either. It is nocturnal, hunting mostly at night and retreating to rest during the day. Resting areas include , gaps underneath buildings and rocks, hollow logs, and even tree branches up to above the ground. This animal is a powerful digger, using the claws on its front limbs excavate its own burrows, though it often inhabits burrows made by other animals instead. Burrow usage is often temporary, though mothers with young tend to stick to one burrow unless there is disturbance.
Though usually hostile towards males, a female will be more tolerant of them when she is receptive, crouching in front of males and allowing them to smell her vulva, sometimes also taking a submissive stance with the neck extended, mouth open and head turned to the side. The male then pulls her into a covered area by the back of her neck. This process may repeat several times before copulation occurs, during which the male mounts the female, occasionally biting onto the back of her neck, while his forelimbs are clasped around her lumbar area as she remains crouched. Copulation may last between 25 and 106 minutes, and throughout this duration the male thrusts his pelvis with pauses in between, while the female makes loud yapping and shrieking sounds. After conception, the gestation period for a striped polecat is about 36 days. The female generally gives birth to one litter per year of two to three young, but may breed more than once if the litter is lost early. When giving birth, the mother lies on her side, regularly licking her genital area while one hind leg is raised. She licks and noses each newborn right after it is born, and ignores it while she delivers the remaining young. The mother protects her young until they are able to survive on their own.
The newborns are altricial and completely vulnerable; they are born blind, deaf, and almost hairless. They are only long and weigh about at birth, and while eye slits and external ear flaps are visible, both are closed. They appear mostly pink because their skin is visible, though dark stripes are already visible at this age. The mother carries her newborns in her mouth by their shoulders or back, and when they reach three weeks old she lifts them by the scruff of the neck instead. At an age of ten days, white hair grows to cover the young, and they begin crawling short distances. The distinctive black and white stripes become visible between 19 and 21 days after birth, and at 39 days they start to walk. The eyes start to open when they are 35 days old, and are fully open after another week. Lower Milk teeth canine teeth erupt at 32 days, at which point the young begin eating the soft parts of prey killed by their mother, and permanent canines grow in before the milk canines are all shed. Young which have begun eating solid food would suckle less, and by an age of eight weeks they were weaned.
On occasion, the striped polecat has been reported to feign death when faced by predators. When doing so, it lies limp on the ground with its back facing upwards, displaying its stripes to the threats. This patterning is an example of aposematism, warning that the polecat can defend itself with its spray and that it tastes foul. The noxious spray contaminates some of the animal's fur, especially that of the tail, deterring any predators which try to bite it while it feigns death. A striped polecat may continue feigning death for over 30 minutes while waiting for its attacker to lose interest and leave.
Visual communication is also used by the striped polecat. When angered or startled, the hair on its back and tail automatically become erect, making the animal appear larger. During friendly interactions with others of its kind, a striped polecat presents its black underbelly, contrasting how it displays the stripes on its back when threatened. Olfactic communication involving the fluids of the anal glands likely also plays a part in regulating social interactions.
Prey may be captured on the ground or extracted from beneath the surface by digging, but the striped polecat does not attempt to catch prey in the air; if it sees a flying or jumping insect, it will go where the prey lands and capture it there. When searching for subterranean invertebrates, the striped polecat pushes its snout into the soil and audibly sniffs, and uses its forelimbs to excavate its prey after detecting it. Most smaller vertebrate prey (including , , birds and small rodents) is killed with a bite to the skull, sometimes while also pinning it down with one or both forelimbs (though this is never done for birds). Larger prey such as rats (whose skulls the polecat cannot bite through) tend to require pinning down with forelimbs and multiple bites to the neck, head or chest to dispatch, and the predator may even roll around or somersault while biting onto the neck. When preying on , the striped polecat will bite the snake's back and briefly shake it vigorously before retreating, moving swiftly to avoid the snake's strikes. This is repeated four to five times to paralyze the prey, after which the polecat pins it down with its forelimbs and kills the reptile with a bite near the head.
The striped polecat may carry prey in its mouth or drag larger prey backwards towards its den before eating, and if it has killed more prey than it needs, it may hoard some in its den. It commonly eats while in a crouched position, sometimes using its forelimbs to hold its food while doing so. Prey is usually eaten whole from the head first, though the feathers and legs of birds and the stomachs of rodents are sometimes left uneaten. One red-lipped snake was reportedly eaten tail first, possibly because the polecat could not distinguish which end was the head after the reptile died. Larger animals (including rats and ) are skinned before they are eaten from the shoulder or flank first.
Killing prey is an innate behaviour, as evidenced by how young striped polecats reared in isolation can do so at the same age as those raised by their mothers, and using the same methods as wild adults. However, egg breaking is not innate, and captive individuals often show little interest in unbroken chicken eggs or fail to break the shells, though they will lap up the contents of eggs and recognize them as food after learning to break them by biting or rolling them against hard objects. Although the striped polecat consumes most amphibians it encounters, it notably does not eat bufonid toads, likely as they are poisonous and unpalatable. The striped polecat has a high metabolic rate and a short gut between 3.2 and 4.3 times the length of its body (excluding the tail), such that food passes through quickly and is excreted via defecation about 165 minutes after consumption, and the animal must actively forage throughout the night to meet its energy requirements.
This species does not drink water frequently, instead obtaining most of its required moisture through its food. When it does drink, it laps water up using its tongue. A male kept in a cage during winter for two weeks did not drink at all during this time, and only drank small amounts of water occasionally when the weather was hot. Captive females with nursing young have been observed dipping their necks or entire undersides into water during very hot weather, possibly to both cool themselves and carry water to their young.
Two nematode species are known endoparasites of the striped polecat, namely Filaria martis and Hepaticofilaria pachycephalum. Dissections of 21 striped polecat carcasses from KwaZulu-Natal revealed that four of these individuals had parasitic nematodes in their stomachs. A malaria-causing parasite, Plasmodium roubaudi, has been found in a striped polecat from Senegal. Rabies has also been recorded in this mustelid. Ixodid ticks are known exoparasites of this mammal, with the species Haemaphysalis zumpti and possibly Haemaphysalis leachi having been found on two individuals from South Africa.
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