Pholidota (Pangolins)

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Pholidota

Pangolins

(Manidae)

Class Mammalia

Order Pholidota

Family Manidae

Number of families 1

Thumbnail description
Mostly nocturnal ant- and termite-eating animals with a long and tapered body shape; they possess a unique body cover consisting of enormously overlapping scales that are movable and sharp edged (because of this they are also known as scaly anteaters); they have no teeth in their elongated heads but do have extremely long, protrusible tongues for catching prey

Size
Head and body length 12–35 in (30–90 cm), tail length 10–35 in (26–88 cm), and weight 2–77 lb (1–35 kg)

Number of genera, species
1 genus; 7 species

Habitat
Southern and Southeast Asia, tropical and subtropical parts of Africa

Conservation status
Lower Risk/Near Threatened: 4 species

Distribution
Tropics and transitional zones (subtropics) bordering the tropics to the north and south; sufficient numbers of ants and termites is paramount to survival, and is the overriding factor as to whether they will remain in a locality

Evolution and systematics

In Europe, the geological range of the order Pholidota is middle Eocene (about 45 million years ago [mya]) to Pleistocene (5–1.6 mya); in Asia, its range is Miocene (24–5 mya) to Present; in North America, it is early Oligocene (about 35 mya); and in Africa, middle Oligocene (about 30 mya) to Present. The order name Pholidota means "the scaled animal."

The origins of pangolins are largely unknown. Many of their current features (such as lack of adult teeth along with signs of primordial teeth in the embryo, chewing musculature and stomach, lack of zygomatic arch, elongated facial skeleton, worm-like tongue, forelimbs as digging tools, and prehensile tail) imply a long independent history. There is a general acceptance that they had an early separation from primitive mammals. By the Eocene era pangolins were highly specialized with such adaptations as horny scales, no teeth, and a diet of only ants and termites. The common name pangolin (possibly from Malayan or French words) refers to the animal's ability to curl up into a ball.

Physical characteristics

Pangolins have a similar shape to armadillos and anteaters. The African species are more specialized in almost every way than the Asian species. Males are usually larger than females, often 10–50% or more heavier. Pangolins are somewhat poikilothermic; that is, their body temperature directly varies with local temperature, with a low average body temperature of 89.9°F (32.2°C).

These strange reptilian-looking animals are distinct from all other Old World mammals by their unique covering of horny body scales (described as similar looking to shingles on a house roof, with all species often described as looking like "living pine cones"). The color, pattern, quantity, shape, and size of the scales differ across the seven species, and can also differ slightly within species, depending on the part of the body covered. They generally have 18 rows of overlapping (imbricate) scales around the body. The African and Asian species are distinguished by the row of scales on the tail. In all species, the row of scales is continuous to the tip of the tail, but the African species have a double row starting two-thirds of the way down to the tip. The scales and skin make up 20% or more of the body weight of most species, although on arboreal species the scales are lighter and thinner than those of the terrestrial species. The coloration of the scales includes dark brown, dark olive-brown, pale olive, yellow brown, and yellowish. Generally, the scales are bilaterally symmetrical, then flattened from the top down, and directed

towards the back of the animal. The number of scales remains the same throughout their life. When scales are lost due to wear they are replaced from the stratum germinativum (which provides for regeneration of cells) in the dermis (skin base). The process of scale replacement occurs when living cells (the epidermis) on the dermal papillae grow to the surface. The epidermis eventually cornifies (the converting of skin cells into horny material) in the depressions between the dermal papillae to make a loose stratum corneum. On top of and at the tip of the papillae, the processes of epidermal cornification lead to the formation of hard (horny) scales.

The scales protect every body part except for the under-side of the head and the sides of the face, throat and neck, stomach, inner sides of the limbs, and on the snout and chin (and in some species on the outer surfaces of the forelegs). During the night the color of the scales is good camouflage. The parts of the body that are without scales are thinly covered with hair. The hair coloration is whitish, pale brown to russet, or blackish, and the skin is grayish with a bluish or pinkish tinge in some areas. There are three or four hairs present at the base of each scale in the Asiatic species, but there are no hairs at the base of the scales in the African species.

Pangolins possess small, short, but powerful limbs and each is tipped with sharp, clawed digits, with the middle digit being the largest. Their powerful front feet have large digging claws, while the shorter and stouter hind feet contain smaller claws. The digging claws of the front feet are folded upward so that the pangolins put down only the outsides of their soles. The limbs are used for digging into termite mounts and anthills. The terrestrial species also use their claws for scooping out underground burrows. In the arboreal species, the claw point grows over the finger and toe cushions. When running, all pangolins, whether arboreal or terrestrial, use primarily their hind legs. Terrestrial pangolins are able to move far distances in an erect position (without touching the ground with their front legs). In movement, they keep the body in a curved position; the tail is carried slightly above the ground and is used to maintain balance. Generally, arboreal pangolins have prehensile tails, while terrestrial ones possess semi-prehensile tails.

Pangolins have small, smooth, and tapered (conical) heads. The eyes are small, with no lubricating glands for the eyelids. The nose is fleshy and has nostrils. Depending on the species, the exterior ears may be reduced in size or absent. The skull moves smoothly into a short neck and later merges directly into the roundish body. The mouth opening (or slit) is constricted (narrowed) with an elongated snout. All species have a primitive cerebrum, and they lack a zygomatic arch or any bony crest for the attachment of muscles. Thus, the skull has few protrusions, cheekbones, bone ridges, or bone cams to

which chewing muscles could be attached. The jaw contains no teeth (except for embryos that contain small primordial teeth, which eventually fall out). The underdeveloped halves of the lower jaw are reduced to thin strips of bone.

Pangolins are edenate; that is, instead of teeth, they use their tongue for foraging. The tongue is extraordinarily long and worm-like, and the salivary glands (which supplies the tongue with a tacky coating of saliva to which insects stick) are very large (measuring 22.0–24.5 in (360–400 cm) and are located in the chest. The tongue measures 6–7 in (16–18 cm) in the small species and about 16 in (40 cm) in the largest species, the giant pangolin. The tongue can be either round or flattened, depending on the particular species, and ends with a fine point. The tongue's average thickness is about 0.2 in (5 mm). When resting, the tongue is contained in a sheath supported by pliable cartilage rods that reaches from the back of the mouth to the pelvic region (the thoracic cavity) at the back of the lower belly. The muscles used by the tongue are attached to the xiphisternum (sternum).

There are 11–16 thoracid (chest) vertebrae, 5–6 lumbar (loin) vertebrae, 2–4 sacral (pelvis) vertebrae, and 21–47 caudal (tail) vertebrae. The lumbar vertebrae do not have articular processes. Pangolins have neither a clavicle nor a collarbone.

The muscular stomach is often called a "chewing apparatus" because pangolins swallow insects whole, where they are then chewed up in the stomach. This is accomplished in part by the stratified "pavement" epithelium, a horny skin layered (like pavement) on the posterior part of the stomach. Pangolins use this adaptation because the stomach must masticate the chitinous exoskeleton of insects (since they have no teeth in their mouths). Opposite to this epithelium is a muscular organ that is studded with horny teeth. Mucus glands and a large gastric gland also contribute to digestion. To also assist in digestion, pangolins swallow sand and stone bits in order to help the grinding action of the stomach.

The sword-like process of the sternum has undergone a modification in all pangolins in order to accommodate the large elongation of the tongue. In the Asian species, the sternum is fairly long (resembling a shovel) and ends in a laterally broadened disc. In the ground species, it forms a long cartilage rod extending to behind the end of the rib cage. In the African arboreal species (the long-tailed pangolin and the tree pangolin), it consists of very long cartilaginous rods extending outside the diaphragm, first toward the rear and then arcing toward the head again.

The powerful tail is quite mobile, even though it is covered with scales. In the arboreal species it is considered fully prehensile (that is, it can be turned around either way, like a corkscrew) and is sometimes about twice the length of the body. The terrestrial species have a shorter, more blunt tail that is not considered fully prehensile. The mobility of tails assists the animals in climbing and supporting themselves when standing upright on the ground. The tail is sensitive at the tip, and can be hooked over a support such as a branch. It can also be used to strike out at an adversary, and when used along with its sharp scales can inflict much damage onto its enemies.

Pangolins can also spray attacking animals with a foul-smelling musky fluid from its bean-shaped perineal (anal) glands located in and around its posterior. These glands also play an important part in intraspecific (within the same species) relations throughout the animal's life. They provide important information concerning the psychophysiological

state of pangolins. For example, the scents prevent aggressive males from approaching each other too closely, helps facilitate the locating of a mate, and are important in mother-young relationships.

Males have a scrotum housed inside abdominal skin so as to avoid heat loss. Females possess two mammae with their auxiliary teats. The urine of pangolins has a pungent odor, and when dried it makes a whitish spot. The dung of pangolins is sausage-shaped and dry in texture. It is black in color when the diet consists mostly of ants, but brown when its main food is termites. Pangolins are often infested with external and internal parasites.

Distribution

Pangolins are found in tropical and subtropical areas south of the Sahara in Africa (excepting the southwest part of Africa), and in southern and southeastern Asia including India, Myanmar, Thailand, southern China, the Malay Peninsula and nearby islands, and through Indonesia to the Philippines.

Habitat

Depending on the species, they inhabit diverse habitat including tropical rainforests, subtropical and deciduous forests, grasslands, thick bush, wooded shrubby slopes, sandy areas, steppes, and open or savanna country. Whatever the area, it must contain ants and termites. They are creatures who usually roam within individual territories, when known, of 38–63 acres (15–25 ha) for males and 8–10 acres (3–4 ha) for females. Ground burrows are about 5.9–7.9 in (15–20 cm) in diameter, usually attain a depth of about 8 ft (2.5 m), terminate in round chambers as much as 6.6 ft (2 m) in circumference, and generally are closed off with dirt when occupied. Arboreal pangolins regularly travel between the ground level and upper layers of the jungle canopy ranging from 5–20 ft (1.5–6.1 m) above ground.

Behavior

Some species of pangolins, the larger ones, are classified as terrestrial (ground-dwelling) (Manis gigantea, Manis temminckii, Manis crassicaudata, and Manis javanica) while others, the smaller species, are classified as arboreal (tree-climbing) (Manis pentadactyla, Manis tetradactyla, and Manis tricuspis). Whether classified as terrestrial or arboreal, some species can dwell both on the ground and in trees.

All species of pangolins are nocturnal except for the predominantly diurnal Manis tetradactyla. Because pangolins are active mostly at night, they have poor vision. Their ability to

hear is only average, and is used little in intraspecific relationships. They make no well-distinguished sounds; with the only noticeable utterances being hisses and snorts. However, large olfactory lobes allow their sense of smell to be exceptionally sharp, playing the major role in finding food and, in all likelihood, playing a major role in intraspecific communication. They have very few expressive behaviors, the most frequent being the closing of the eyes and the sticking out of the tongue. Pangolins are generally shy, solitary, and unsociable creatures who only rarely associate with a conspecific.

Panglolins are slow and deliberate movers. Most are good climbers, and some also swim. The terrestrial species will rest and sleep during the day in burrows that they have previously dug (or those dug by other animals), while the arboreal species find haven in hollow trees. For additional protection from small- and medium-sized enemies, they roll up (basically) into a ball when sleeping. They do not actively defend a fixed territory from neighboring animals of the same species. However, they do repeatedly mark selected trees, branches, and rocks with secretions from their anal glands and urine, which announces to neighboring and trespassing animals that the area is already occupied. The terrestrial species regularly mark their territories with droppings, and arboreal species may do so as well.

All species can move quickly when alarmed. If unable to reach shelter, they will often curl into a tight ball with their scaled limbs and tail protecting the soft under-parts. When in this position the sharp-edged scales are erected as protective armor. Movements of the scales and twitches of the tail apparently deter predators. They do not appear to use their fore-claws in defense. The animals will also expel urine and posterior gland secretion in defense of their immediate safety. Often a stream of urine is released if a pangolin is unrolled by force. Feces may also be released, which is often combined with secretion from the anal glands.

Pangolins are plantigrade; that is, they walk on the soles of their feet with heels touching the ground. When they walk on all four limbs their toes are doubled under and the tips of the long nails are placed on the ground. The large digging claws of the forefeet are held inward by terrestrial species, which walk on the outer sole. The arboreal species bend the claw downward when traveling on the ground. In walking on the ground, primarily the hind limbs are used. They stop periodically and raise themselves up, supporting themselves on

their hind legs and tail. In this position, with the front of the body erect and the head protruding, they smell or look out for possible enemies. At a fast pace, the tail is lifted from the ground.

The giant pangolin (M. gigantea), ground pangolin (M. termminckii), long-tailed pangolin (M. tetradactyla), and tree pangolin (M. tricuspis) are all good swimmers, holding only the head above water while swimming with a "doggy paddle" motion. They are able to cross narrow rivers easily, but tire on longer journeys.

Feeding ecology and diet

Pangolins are insectivorous, with a very limited diet almost exclusively of insects, mostly termites and ants (and some soft-bodied insects and larvae) that are located by scent. The larger species sometimes eat larger insects. Variations in diet may be due to the availability of local supplies or on seasonal variations. Pangolins show a strong preference for particular species of ants and termites to eat, often rejecting all others. All species drink water regularly, lapping it up with their tongue in a flicking motion.

Pangolins developed special adaptations because of their particular diet. Live insects are caught with their long, proboscis-like tongue, which is sheathed in a special membrane attached to the pelvis. The tongue is about 27 in (70 cm) long when it is fully extended from its mouth. The tongue remains coiled up in the animal's mouth when at rest. In preparation to catch prey, pangolins will secrete viscous saliva from special glands in the abdomen onto the tongue. When the tongue is darted into the chambers of a mound, the sticky tongue will trap insects living inside. Since they have no teeth, all food is crushed in the lower section of the stomach that leads to the intestines. This area normally contains small pebbles that function to crush food. While eating, thickened membranes protect the eyes of pangolins from insects, and special muscles seal its nostrils and ear openings to shield it from the bites of ants. Ants that reach the scales are often shaken off.

Terrestrial pangolins scrape funnel-shaped holes around a termite hill until they find termites. They do this by using their tail and hind legs as a "tripod," digging with their front feet. With the feet held close to the right and left sides of the head, the claws tear open the insect nest. The snout gradually penetrates the mound. With its long, sticky tongue, the animal catches the insects with fast movements. The termite hill is seldom destroyed completely, so pangolins will return to the same termite hill after the remaining insects have rebuilt the hill. When pangolins locate old animal droppings containing termites, they take the pellets with their forelimbs and turn over onto their backs. They then hold the dropping between their claws above its stomach, and raise their head and lick off the termites. Arboreal pangolins often break up tree nests by anchoring themselves in the branches with their hind legs and prehensile tail. The claws of the forefeet then dig precisely to the left and right of the mouth, which slowly advances into the cavity formed in the nest. The worm-like tongue is constantly stabbing into the narrow passages of the termite nests. Strictly tree-dwelling pangolins hunt and feed only in the nests of arboreal termites, unable to break open the nests of ground termites. They might eat ground termites, however, if another animal has previously opened the nest.

Reproductive biology

Female pangolins have a bicornuate uterus (a heart shaped uterus with two horns) and two pectoral (breast) nipples. Males have inguinal (near the groin) testes. Several research studies suggest that some populations are capable of breeding throughout the year but most species are believed to be born between November and March. The gestation period is 120–150 days. Females usually give birth to one young, sometimes two, and rarely three, with a birth weight of 3–18 oz (90–500 g). Newborns have soft scales that do not overlap. The scales are lighter in color than in the adult, and harden after a couple of days.

There is no reliable information available on weaning or sexual maturity, but weaning is believed to begin at three months and sexual maturity believed to occur at two years. While sleeping and when alarmed, the mother rolls up around the young, which also rolls up. Beginning in the first few days, the baby makes short excursions with the mother, riding at the base of the tail or on the back and grabbing onto the scales. The mother will occasionally leave the baby behind on a branch, while feeding, and then pick it up later. The juvenile first eats insects found between the mother's scales, and later picks insects while the mother is breaking open a nest. Closer to maturity, it will dig for itself. At five months of age, the youngster will leave its mother. Females will readily take over orphans of other females. Males share a burrow with females and young ones. Life span in the wild in not known, but they can live up to 12 years in captivity. The mating system is not known.

Conservation status

The Indian pangolin (Manis crassicaudata), Malayan pangolin (Manis javanica), Chinese pangolin (Manis pentadactyla), and ground pangolin (Manis temminckii) are listed as Lower Risk/Near Threatened by the IUCN. Sanctions often apply to trade in pangolins and their products. Much of their habitat is being depleted due to the eroding of tropical rainforests and other areas. Their main threats are humans, large cats (especially leopards, lions, and tigers), hyenas, and pythons. The population densities and territorial ranges of all pangolins continue to decline.

Significance to humans

All species are hunted and trapped for their meat, which is often a favorite delicacy of indigenous people, and for their skins and scales, which are involved in international trade. Their scales are often used for adornment and good-luck charms; for example, they are made into rings and used as charms against rheumatic fever. In Asia, powdered scales are believed to be of medicinal value. The Chinese people have extensively hunted pangolins because the animal's scales are traditionally thought to contain medicinal attributes, such as an antiseptic in fighting fever and skin disease. Its skin is thought to be an aphrodisiac by some hill tribes.

Species accounts

List of Species

Chinese pangolin
Indian pangolin
Malayan pangolin
Giant pangolin
Ground pangolin
Long-tailed pangolin
Tree pangolin

Chinese pangolin

Manis pentadactyla

subfamily

Maninae

taxonomy

Manis pentadactyla Linnaeus, 1758, Taiwan.

other common names

French: Pangolin de Chine; Spanish: Pangolín chino.

physical characteristics

Chinese pangolins have a head and body length of 21–32 in (50–80 cm), a tail length of 10–16 in (26–40 cm), and a weight of 4–20 lb (2–9 kg). They have about 18 rows of overlapping scales. The yellow-brown scales are bony, up to 2 in (5 cm) across, and encompass all of the body (including the tail) except for its snout, cheeks, throat, inner limbs, and belly. They have hairs at the base of the body scales. Their limbs are slender with comparatively long and sharp claws, an important aid in climbing. Chinese pangolins have a small, pointed head, a very round body, and a narrow mouth. The nose is fleshy and has nostrils at the end, and the thin tongue, as long as 16 in (40 cm), scoops up ants and termites. Their small, external ears are better developed than are those of the other pangolins. The strongly prehensile tail and long claws make this pangolin very agile in trees and a powerful burrower.

distribution

Westward through Nepal, Assam and Sikkim (in northeastern India), eastern Himalayas, Myanmar, northern Thailand and Indochina, southern China, Taiwan, and Hainan.

habitat

They inhabit subtropical and deciduous forests and grasslands. Burrows are often built adjacent to termite nests and extend further below the surface during the cold winter months. During the summer months they sometimes occupy burrows for just a few days. It is unclear whether the winter burrow is maintained during warmer months. Although predominantly a terrestrial species, it has been observed in the jungle canopy up to 20 ft (6 m) above the ground.

behavior

Chinese pangolins are extremely shy, and are very agile tree climbers. They are classified as arboreal and often hang by the tip of their tail. Chinese pangolins generally are not aggressive, but males can fight over mating rights. They dig tunnels up to 9 ft (3 m) long (sometimes in as little as 3–5 minutes) that terminates in a den. The den is closed off while they are inside. They swim rapidly with undulating movements. When rolled into a ball, no soft areas are exposed.

feeding ecology and diet

They feed primarily on the ground, mostly digging for termites and ants with its strongly clawed feet. Their range corresponds to those of its preferred subterranean termite species Coptotermes formosanus and Cyclotermes formosanus. They forage through a surrounding area that is about 165–330 ft (50–100m) in circumference, and then move onto another area when food becomes scarce.

reproductive biology

Males fight violently over females. Mating occurs during a 3–5 day period in late summer or early autumn. Young are born in a winter burrow, and emerge with the mother in the spring. The gestation period is unknown, but in Nepal, Chinese pangolins were found to reproduce during April and May. Females give birth to 1–2 young at a time. Birth weight and head-and-body length are generally unknown but have been reported to be about 1 lb (0.5 kg) and about 18 in (45 cm) respectively. Scales in young animals are purplish brown. When a baby Chinese pangolin nurses, the mother lies on her back or side. While resting, she holds the baby pressed to her abdomen. Young are able to walk at birth, but are carried on the mother's tail or back. When the mother is feeding, the offspring is left alone. Weaning, sexual maturity, and life span are unknown. Males have been observed to exhibit good parental instincts and share a burrow with the female and young.

conservation status

Lower Risk/Near Threatened. Their main enemies are humans, large cats (especially leopards, lions, and tigers), hyenas, and pythons. They live in many protected forests throughout their range. Land development often threatens unprotected habitats.

significance to humans

Chinese pangolins are hunted for their meat, which is considered a delicacy in many areas such as Vietnam and Hong Kong.

Indian pangolin

Manis crassicaudata

subfamily

Maninae

taxonomy

Manis crassicaudata Gray, 1827, India.

other common names

English: Thick-tailed pangolin; French: Grand pangolin de l'inde; Spanish: Pangolín indio.

physical characteristics

Indian pangolins have a head and body length of 2.0–2.2 ft (60–65 cm), a tail length of 1.5–1.8 ft (45–55 cm), and a weight of 17.6–19.8 lb (8–9 kg). Male Indian pangolins may be as much as 90% heavier than females. They have large, pale yellowish brown or yellow-gray scales, with brownish skin and hair; with about 14–16 rows of scales on the tail. Scales make up about one-fourth to one-third of body weight. The head is small and triangular in shape, and the body is slender and long. They possess small, undeveloped, external ears, have a scaleclad tail, and also have hairs at the base of the body scales. Each limb contains five powerful claws that are adapted for digging burrows or locating their prey's nests. They have no teeth so their two-chambered stomach crushes all their food. The tongue is 9–10 in (23.0–25.5 cm) long, and is their main way to capture food. Because the tongue is so long they have muscular attachments extending all the way to the pelvis.

distribution

India, Nepal, Pakistan, Bangladesh, and Sri Lanka.

habitat

They prefer hilly regions and plains, mostly in tropical areas. The species has been seen in tropical rainforests, subtropical thorn forests, plains, and the lower slopes of mountains. Burrows range in depth and depend on soil type. Soft soils will allow the animal to dig burrows about 20 ft (6 m) deep, while rocky, hard soils will allow depths of about 6 ft (2 m). They usually close the burrow entrance with loose soil when they are inside, which hides the entrance from predators..

behavior

Indian pangolins are largely nocturnal, sleeping and resting in burrows or among rocks during the day. They are predominantely terrestrial but also have great agility for climbing with their prehensile tail and sharp claws. They are good diggers, often making tunnels that end in an enlarged cave. Indian pangolins live mostly alone with the exception of the mating and breeding season, when adult male and female pangolins are found in the same burrow. They protect themselves from predators by curling up into a ball, exposing only its scales. Anal glands emit a foul smelling, yellow fluid for additional defense against enemies.

feeding ecology and diet

Indian pangolins eat termites, ants, termite and ant eggs, and other insects from ground mounds and hills.

reproductive biology

Their gestation period is about 65–70 days. Births may occur throughout the year, with births having been recorded in January, March, July, and November. Females give birth to 1–2 young at a time. Weight at birth is 8.2–8.6 oz (230–240 g). Scales of young are soft, with fully functioning eyes and legs. At about one month of age, young are carried on the dorsal base of the mother's tail when foraging. At about three months of age the young are (believed to be) weaned. Sexual maturity and life span in the wild for Indian pangolins are unknown.

conservation status

Lower Risk/Near Threatened, and listed on CITES Appendix I. Their main enemies are humans, large cats (especially leopards, lions, and tigers), hyenas, and pythons.

significance to humans

They are hunted for meat, especially in Pakistan because some of their body parts are used for medicinal purposes. Scales are thought to be an aphrodisiac, and often used to make necklaces and shoes.

Malayan pangolin

Manis javanica

subfamily

Maninae

taxonomy

Manis javanica Desmarest, 1822, Java, Indonesia.

other common names

French: Pangolin javanais; Spanish: Pangolín malayo.

physical characteristics

Mayalan pangolins have a head and body length of 1.6–2.0 ft (50–60 cm) and a tail length of 1.6–2.6 ft (50–80 cm). Their weight is unknown. They have amber-yellow to blackish brown scales, with whitish skin and fine, light hairs at the base of the body scales. The species possesses small, undeveloped, external ears and a scale-clad tail.

distribution

Myanmar, Thailand, Indochina, Malay Peninsula and many small nearby islands, Sumatra and Nias and Pagai islands to west, Bangka and Belitung islands, Java, Bali, Borneo, Palawan and Culion islands (Philippines), and Lombok.

habitat

This species prefers sandy open country.

behavior

Malayan pangolins are nocturnal, and are predominantely terrestrial but also like to climb. During the day they sleep, often curled up in forked branches, in ferns, or in other plants growing on trees. They move with agility both on the ground and in trees. They are also able to hang by the tip of their tail.

feeding ecology and diet

Some zoologists report that they eat mostly termites, while others say that their primary food is ants and their pupae.

reproductive biology

Their gestation period is unknown. Females give birth to 1–2 young at a time. Weight at birth is unknown. Weaning, sexual maturity, and life span are unknown.

conservation status

Lower Risk/Near Threatened.

significance to humans

They are hunted for meat.

Giant pangolin

Manis gigantea

subfamily

Smutsiinae

taxonomy

Manis gigantea Illiger, 1815, type locality not known.

other common names

French: Pangolin géant; Spanish: Pangolí gigante.

physical characteristics

Giant pangolins have a head and body length of 30–36 in (75–90 cm), a tail length of 18–30 in (50–80 cm), and a weight of 55–80 lb (25–35 kg). The female is smaller than the male. They are strictly ground dwelling (terrestrial) animals with broad sole cushions and blunt claws on the hind feet, and with forefeet containing large digging claws. The species is the largest of the order Pholidota. They have large grayish brown scales, with whitish skin and sparse hairs. The tongue measures the longest of the seven species, at about 16–27 in (40–70 cm), and can be pushed out 14–16 in (36–40 cm). The salivary glands, which supply the tongue with tacky saliva to which ants and termites adhere, are the size of goose eggs. They do not have external ears, have scales on the tail (but do not have scales beneath the tail), and have a breastbone that is very long.

distribution

Along the equator in Africa, from Senegal to Uganda and Angola.

habitat

Giant pangolins prefer tropical rainforests, but will also inhabit forests and savannas. They do not occupy high altitudes. They usually live near water. Burrows may be up to 16 ft (5 m) deep and 130 ft (40 m) long.

behavior

They are nocturnal and ground-dwelling (terrestrial) animals, being active mainly between midnight and dawn when searching for food. Giant pangolins generally are observed singly, but pairs can be found with young. Terrestrial burrows are dug in which to sleep inside during the day. They often dig around large termite nests, both above and below the ground, using powerful fore-claws. The species uses slow and deliberate movements. When walking on all four legs, they curl in their front paws to protect the sharp front claws, actually walking on the outside of the wrists rather than on the palms. They can walk only on the hind limbs, with the help of their long tail for balance. Giant pangolins often hide inside or under stilt or platform roots of large trees.

If threatened, giant pangolins will often roll themselves into a ball, a technique that protects themselves against most enemies. If necessary, they will lash out against enemies with their sharp-scaled tail and spray urine and anal gland secretions. If near water, they will plunge into the water, rather than roll up, where they can stay underwater for considerable time, either swimming below the surface or walking along the bottom. At times a giant pangolin may rise on its hind legs and even attempt to defend itself by waving its immense fore-claws at its adversary. Unfortunately, with poor eyesight and hearing, they usually have problems identifying where their possible attackers are located.

feeding ecology and diet

They have a limited diet, feeding mostly on termites and ants but also sometimes eating larger insects. Their large digging claws enable them to tear open the subterranean and mounds-type nests made by ground termites. They may eat up to 200,000 ants in a night, with a stomach capacity of 0.5 gal (2 l). A ready access to drinking water is a necessity.

reproductive biology

The gestation period is about five months. Females give birth to one young at a time. Young are usually born in an underground nest. Weight at birth is 14.2–17.8 oz (400–500 g). Newborns have soft scales, which will harden in several days. Newborns cannot walk on their legs, but are active and can crawl around on their stomachs. They will accompany their mother on feeding trips, often sitting on the base of her tail. Weaning, sexual maturity, and life span are unknown.

conservation status

Not threatened, but deforestation for timber, agricultural development, and urban development have decreased the size of their habitat.

significance to humans

They are hunted for meat, however in some tribes its meat is forbidden to be eaten.

Ground pangolin

Manis temminckii

subfamily

Smutsiinae

taxonomy

Manis temminckii Smuts, 1832, northern Cape Province, South Africa.

other common names

English: Cape pangolin, South African pangolin, Temminck's ground pangolin, scaly anteater; French: Pangolin de Temminck; Spanish: Pangolín del cabo.

physical characteristics

Ground pangolins have a head and body length of 20–24 in (50–60 cm), a tail length of 14–20 in (35–50 cm), and a weight of 33.0–39.6 lb (15–18 kg). (Ground pangolins are similar in most respect to Chinese pangolins.) They do not have external ears, have scales on the tail (but do not have scales underneath the tail), and the rear part of the breastbone is very long. The hind feet have broad sole cushions and blunt claws, and the forefeet contain large digging claws. Their sharp scales are large and moveable, with colorations of grayish brown to dark brown. Scale coloration helps them to blend into many different surroundings. The skin is whitish with fine, dark hairs. Ground pangolins have small, pointed heads and small eyes that are protected by specialized thick eyelids. They bury their feces in small depressions that it scrapes in the ground.

distribution

From Chad and Sudan in central Africa, south through Kenya and Tanzania, to Namibia and the northern parts of South Africa.

habitat

Ground pangolins prefer steppes, prairies, thick brush, open grasslands, and savannas with both high and low rainfall amounts. They show little territorial behavior. Burrows are usually about 6–8 in (15–20 cm) in diameter, and extend several feet (meters) underground.

behavior

Ground pangolins are nocturnal, ground-dwellers (terrestrial) animals that occasionally climb bushes and trees. They are solitary animals, only joining together during mating. The species dig burrows inside which to sleep during the day. Ground pangolins move rapidly over the ground, sometimes up to 160 ft (50 m) per minute. They often halt, rise with the support of the tail, sniff the air, and look for possible predators.

feeding ecology and diet

They tear open termite mounds and ant nests, both in trees and on the ground, with their large claws, and lick up insects and their larvae. They are selective in what species of termites they eat. The termites of the genera Amitermes, Ancistrotermes, Macrotermes, Microcerotermes, Microtermes, Odontotermes, and Trinervitermes are most often eaten by first detecting (with their keen sense of smell) these preferred genera before opening the hill.

reproductive biology

Males may fight for the opportunity to mate. Females breed at any time of the year, even if they are still rearing other young. The gestation period is about 120–140 days. Females give birth to one, sometimes two, young at a time. Young are born in ground dens. Birth weight is 10.7–14.2 oz (300–400 g). They are carried outside on the mother's back or tail at 2–4 weeks of age. Young will begin to feed on their own by three months of age, but are still carried until they weigh about 7 lb (3 kg). Weaning, sexual maturity, and life span are generally unknown.

conservation status

Lower Risk/Near Threatened. This species is very vulnerable to population decreases because of its great economic value to humans and habitat loss to agriculture.

significance to humans

They are often killed for their flesh and scales. Ground pangolins are called bwana mganga "bwana doctor" in East Africa because every part of their body is said to possess healing properties.

Long-tailed pangolin

Manis tetradactyla

subfamily

Smutsiinae

taxonomy

Manis tetradactyla Linnaeus, 1766, West Africa.

other common names

None known.

physical characteristics

Long-tailed pangolins have a head and body length of 12–16 in (30–40 cm), a tail length of 22–28 in (55–70 cm), and a weight of 2.6–5.5 lb (1.2–2.5 kg). They are the smallest of the order Pholidota. The scales are dark brown in color with yellowish edges. Nine to 13 rows of scales encompass the entire top of the species. Their hair is dark brown to black. They have a very long, prehensile tail, the longest tail of all of the species and almost two-thirds of its entire body length. There is a short, bare patch at the tip of the tail. This species possess 46–47 caudal vertebrae, the largest number of all mammals. They do not have external ears, have scales on the tail (but do not have scales underneath the tail), and the rear part of the breastbone is very long. The sternum consists of two extraordinarily long cartilaginous rods extending outside the diaphragm, first toward the rear and then arcing toward the head again. They have short, thick limbs and digits with long curved claws.

distribution

From Senegal to Uganda and Angola.

habitat

They prefer tropical rainforests, and not the edges of forests. Their territory is restricted within the forest canopy, but it is unknown if they maintain a home territory.

behavior

They are the only species of pangolin that is not nocturnal: they are predominantly diurnal, eating during the day. They are very good climbers (arboreal), able to easily scale vertical tree trunks. Contact with the ground is rare. They climb with the front legs gripping the tree simultaneously, and with the body curved. The hind feet are then loosened up and are anchored close behind the front feet. With the hind feet and the tail giving the body necessary support, the front feet grip the bark further up. They are also able to hang by the tip of their tail. When hanging by its tail and wanting to resume climbing, they will often climb up their tail. They sleep in hollow trees, liana curtains, forks in trees, or epiphytes (plants growing on trees), often rolled up in the shape of a ball. The animals often sun themselves while stretched out on a tree limb or branch.

feeding ecology and diet

They eat mostly ants, preferring tree ants of the genera Camponotus, Catalacus, and Crematogaster. They will seek the soft, hanging nests of ants and termites, or will attack the ant columns that move among the leaves.

reproductive biology

It is believed that they breed throughout the year. When mating, the male and female will intertwine tails and face each other ventrally. The gestation period is unknown. Females give birth to one young at a time. Birth weight is 3.6–5.4 oz (100–150 g). The young will ride on the mother for up to three months. Weaning and life span are generally unknown, and sexual maturity is thought to be around two years.

conservation status

Not threatened.

significance to humans

They are hunted for meat.

Tree pangolin

Manis tricuspis

subfamily

Smutsiinae

taxonomy

Manis tricuspis Rafinesque, 1821, West Africa.

other common names

English: African tree pangolin, small-scaled pangolin, three-pointed pangolin, white-bellied pangolin.

physical characteristics

Tree pangolins have a head and body length of 13.75–17.75 in (35–45 cm), tail length of 19.3–23.5 in (49–60 cm) 16–20 in (40–50 cm), and weight of 3.9–5.3 lb (1.8–2.4 kg). Pangolin scales are comparatively small, with a brown-gray to dark brown color. Their distinctive dorsal scales have three fairly pronounced points (hence the name "tricuspis") on the free edge. The scales are often worn down in older individuals. They have white skin and hair; do not have external ears, have scales on the tail (but do not have scales beneath the tail), and have a very long rear part of the breastbone. Their limbs are slender with comparatively long claws, an important aid in climbing, as is their very long prehensile tail. They sleep during the day on branches of trees or in holes, which they dig out of the ground. They emerge at night to feed. The sternum consists of two extraordinarily long cartilaginous rods extending outside the diaphragm, first toward the rear and then arcing toward the head again. The long sternum is an adaptation to accommodate the animal's extremely elongated tongue. The intestine of the tree pangolin is about 6 ft (2 m) long. They drop their feces anywhere. Body temperature fluctuates between 86–95°F (30–35°C), primarily due to the outdoor temperature.

distribution

From Senegal to western Kenya, and south to Angola and Zambia.

habitat

They prefer tropical rainforests, sometimes living along the forest edges and the savannas in the southern parts of Congo (formerly Zaire) and in Zambia. The territory of males covers 37.5–62.5 acres (15–25 hectares), while the territory of females covers 7.5–10.0 acres (3–4 hectares); both generally in the lower strata of the forest.

behavior

Tree pangolins are nocturnal and truly arboreal. With the aid of a very prehensile tail they climb with the front legs gripping the tree and with the body curved; the hind feet are then loosened up and are anchored close behind the front feet; and with the hind feet and the tail giving the body support, the front feet grip the bark further up. They are also able to hang by the tip of their tail. When hanging by its tail and wanting to resume climbing, they will climb up the tail, placing its gripping claws between the side scales of its tail. They climb down head first, in the same way as going up. Rest periods are spent in hollow trees, epiphytes, or excavated termite hills. Sleeping places are usually located 30–40 ft (10–15 m) above the ground, and they sleep rolled up in the shape of a ball. They spend most of their active time searching for termites on the ground.

Females are active for 3–4 hours every night and usually travel an average of 1,300 ft (400 m) in one night. They follow zigzag or circular courses, usually returning to their previous shelter. As a result, females usually only utilize a portion of their territory. Because of this pattern (and because of markings left by secretions of the posterior glands), different females rarely meet. If a female should locate fresh markings of another female, she will return to her own territory. Males are active for 2–10 hours every night and travel an average of 2,200 ft (700 m) in one night. Males use much more of their territory each night, with their paths being longer and straighter. This pattern allows males to encounter females more frequently. As a result male territory overlaps several female territories. During the rainy season they may become inactive for several days.

Tree pangolins move rapidly over the ground, sometimes as fast as 180 ft (60 m) per minute. They often stop, rise with the support of the tail, sniff the air, and search for enemies. When sensing an enemy they often climb trees until the danger has passed.

feeding ecology and diet

They feed on ground and tree ants and termites, preferring tree ants of the genus Nasutitermes and Microcerotermes, and ignoring ground ants such as Crematogaster. The quantity of insects consumed daily is 5–7 oz (150–200 g) with 3–4 hours of daily foraging for females and up to 10 hours for males. Their stomach can hold up to 0.5 gal (2 l) of insects. They use their powerful forelimbs to sweep up insects with swift movements of their long tongues. They drink water often.

reproductive biology

When a female is ready to mate, both female and male will intertwine during mating, and the pair will lie ventrally opposed. The gestation period is about 140–150 days. Females give birth to one young at a time. Birth weight is 3.2–5.4 oz (90–150 g). The weaning period takes about five months. Sexual maturity and life span are unknown. The young will crawl up on the mother immediately after birth in order to find her pectoral nipples. They are able to hold on by the claws of the forefeet, either to the mother or to a limb. At this time, they are unable to walk, but will use their tail to cling to the mother.

conservation status

Not threatened.

significance to humans

They are important to local indigenous people for its meat. The scales are thought to have medicinal value in the form of antiseptic to counter fever and skin disease by Chinese cultures. Their hide is used for making shoes and other leather goods.

Resources

Books

Burnie, David, and Don E. Wilson, eds. Animal. Washington, DC: Smithsonian Institution, 2001.

Feldhamer, George A., Lee C. Drickamer, Stephen H. Vessey, and Joseph F. Merritt, eds. Mammalogy: Adaptation, Diversity, and Ecology. Boston: WCB McGraw-Hill, 1999.

Gould, Dr. Edwin, and Dr. George McKay, eds. Encyclopedia of Mammals. 2nd ed. San Diego: Academic Press, 1998.

Honacki, James H., Kenneth E. Kinman, and James W. Koeppl, eds. Mammal Species of the World: A Taxonomic and Geographic Reference. 2nd ed. Lawrence, KS: Allen Press and the Association of Systematics Collections, 1982.

Macdonald, David., ed. The Encyclopedia of Mammals. New York: Facts on File, 1984.

Martin, Robert Eugene. A Manual of Mammalogy: With Keys to Families of the World. 3rd ed. Boston, MA: McGraw-Hill, 2001.

Nowak, Ronald M. Walker's Mammals of the World, volume II, 6th ed. Baltimore and London: Johns Hopkins University Press, 1999.

Special Publications Division (prepared by). National Geographic Book of Mammals. Washington, DC: National Geographic Society, 1981.

Whitfield, Dr. Philip. Macmillan Illustrated Animal Encyclopedia. New York: Macmillan Publishing Company, 1984.

Wilson, Don E., and DeeAnn M. Reeder, eds. Mammal Species of the World: A Taxonomic and Geographic Reference. 2nd ed. Washington, DC: Smithsonian Institution Press, 1993.