![]() Spines vary considerably among species but can be roughly classified into seven groups: (1) stiletto-like quills that are stiff, flattened, with sharp points and longitudinal grooves, which cover most of body (2) spikes that are thick, inflexible, and In genus Hystrix, in contrast, spines develop into hollow quills that reach 7.9 in (20 cm) in length. In genus Trichys, for example, spines are short, flattened, and not especially well developed. Longest spines tend to be found on rump and shortest on cheeks. All spines lack the barbules that characterize spines of New World porcupines. Spine coloration is brownish or blackish, often with conspicuous white bands around them. The head, body, and (in some species) tail are covered by barb-less spines, which are thick, stiff, sharp modified hairs, as much as 13.8 in (35 cm) in length. The most characteristic physical features are the quills, spines, and bristles. When walking or running, the entire sole of the foot touches the ground. ![]() Claws are short and soles of feet are smooth, naked, and fitted with pads. On the two forelimbs, each foot has four well-developed clawed digits and one thumb, which is regressed and externally visible only by nail and thumb pad each of two hind feet has five functional digits. Features (generally called postorbital processes) possibly evolved to enlarge chewing volume and to allow animals to smell underground bulbs.īoth forelimbs and hind limbs are short and heavily built as a result, Old World porcupines are excellent diggers and sometimes construct their own burrows. The infraorbital foramen (lower orbital cavity in upper jawbone) is unusually enlarged, resulting in portions of masseter (chewing) muscle being penetrated through it, thus enabling muscles to adhere to the frontal side surface of the upper jawbone (called hystricomorphous). The skull is long and sometimes inflated with air chambers over the rostrum and top of head. ![]() Large, chiselshaped lower and upper incisor teeth do not have longitudinal grooves and grow throughout life molars are rooted and have irregular enamel folds that are rapidly worn down. The upper lip is cleft, and the tip of the nose is stubbed and covered with velvety hairs. Nostrils are usually S-shaped, with a sharp sense of smell. Eyes and external ears are generally small, with a poor sense of sight but a sharp sense of hearing. The tail is very short in some species, but can reach around half the head-body length in others. Physical characteristicsīodies range from a rather slender build, in the genus Trichys, to a clumsy and stocky build, in the genus Hystrix. Old World porcupines evolved from Miocene (24 million to 5 million years ago ) in Asia, from Pliocene (5 to 1.6 mya) in Europe, and from Pleistocene (1.6 mya to 10,000 years ago) in Africa. Habitat Adaptable to a variety of habitats and can be found in such areas as deserts, rocky areas, mountains, savannas, croplands, and forestsĬonservation status Vulnerable: 1 species Lower Risk/Near Threatened: 2 species.ĭistribution Generally the warmer regions of Asia, Europe, Africa Evolution and systematics Number of genera, species 3 genera 11 species (extant) Thumbnail description Medium-sized to large rodents, with a heavyset body, a tail not more than half as long as the head and body, and short limbs spines, quills, and bristles cover the back, sides, and parts of the tail
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