Manis gigantea, Illiger, 1815
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publication ID |
https://doi.org/ 10.5281/zenodo.5720458 |
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DOI |
https://doi.org/10.5281/zenodo.5720446 |
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persistent identifier |
https://treatment.plazi.org/id/EC7D87A1-FFF5-FF88-E243-F3BDC224F904 |
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treatment provided by |
Conny |
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scientific name |
Manis gigantea |
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5. View On
Giant Pangolin
French: Pangolin géant / German: Riesenschuppentier / Spanish: Pangolin gigante
Other common names: Giant Ground Pangolin
Taxonomy. Manis gigantea Illiger, 1815 View in CoL ,
no type locality indicated.
Sometimes included in the genus/subgenus Smutsia. Monotypic.
Distribution. Discontinuously distributed, from Senegal to Ghana in W Africa, and in the C African rainforest block from Cameroon to Uganda, W Kenya, and W Tanzania, and south to extreme NW Angola, also present in Bioko I. Sightings from Dahomey Gap and S Nigeria remain unconfirmed. View Figure
Descriptive notes. Head-body 67-81 cm, tail 58-68 cm; weight ¢. 30 kg. The largest and heaviest of the pangolins. One pair of mammae. Adult males larger than females. Head cone-shaped and muzzle long; the latter is thicker than in other species. Nose pad color similar to the pale yellow—pink skin (may reach bright purple bright). Auditory orifice without ear pinna. Eyes small and iris dark. Massive scaled armor covering the upper face and the whole body except the belly and innerside of legs. Hairs bright, very thin and short on belly (less than 0-3 cm); very sparsely distributed on other skin surfaces, except around the auditory orifice, where they form a tuft. No hairs project between scales. 15-16 dorsal scale rows. The scales on the distal part of the body are at least twice as large as first rows of postscapular scales; scales are uniformly colored, from beige to gray-brown. Tail length is shorter than head and body length. On the tail, the medio-dorsal row of scalesis interrupted before the tip; in juveniles and subadults, the posterior margin is three-cusped (can also be observed on back). These cusps—and original shape—disappear with age because of natural abrasion. Ventral part oftail entirely covered by scales. Legs massive, especially hindlegs; forelegs shorter than hindlegs. Five long and slightly curved claws on forefeet, especially the third one; pangolins walk with their weight on the external border of the claws, with claws pointing backwards. The five claws on the hindfeet are kept shorter by soil abrasion (plantigrade posture) than in arboreal species; the hind claws are only slightly curved. Large anal glands open via ducts on both sides of the anus. Skull 13-16 cm long, cone-shaped and massive. 23-27 caudal vertebrae.
Habitat. Present in riparian forest, rainforest, savanna-forest mosaics; can survive in high-rainfall secondary grasslands. Highly dependent on water. Avoids human-impacted areas.
Food and Feeding. Almost strictly myrmecophagous; genera preyed upon include Macrotermes, Pseudacanthotermes, Apicotermes, Protermes (termites), and Palthothyreus and Anomma (ants). Other arthropods are also consumed, such as water beetles ( Dytiscidae ) through licking of water surface. In Gabon, seems closely dependent on ground, mound-building termites. Requires a huge quantity of available prey biomass, consuming up to two liters of prey per day. Uses olfaction to forage between midnight and dawn, opportunistically scratching soil and substratum with its powerful foreclaws; seasonal variations in feeding activities are unknown. May undergo long feeding stasis (aestivation) during unfavorable climatic periods, probably compensated by periods of high storage of body fat. To feed on termites in the substratum, usually digs tunnels that rarely reach more than one meter below ground level. May walk several kilometers and visit up to a dozen termite mounds in a night. The same mounds can be visited each night. After a Giant Pangolin raid, termite colonies are only partly destroyed and frequently recover. When feeding, the rostral part of the tongue, which is thin enough to pass through fissures,is rapidly inserted and withdrawn to capture prey. The lingual system is dramatically adapted to preying on ants and termites. The tongue is covered with colorless, viscous saliva secreted by submandibular glands. With its numerous sensory receptors and a large, terminal organ similar to a pressure receptor, the tongue is very sensitive to touch. It literally acts as a “protrude and withdraw” touch organ; chewing is minor given the lack of teeth and few taste buds present. The flat mandible and weak temporal-mandibular joints, coupled with the quasi-absence of masticatory muscles, give limited movements to the jaw. The symphyseal area of the mandibles forms a flat surface where the tongue can slip; extrinsic lingual muscles are attached on ridges present inside the mandible. The tongue can be 70 cm long. It is attached behind the larynx and trachea to a characteristically modified xiphisternum (xiphoid process). Xiphoid cartilages form two elongated bars that pass through the iliac fossa and then curve dorso-laterally to end up with a spatula shape in the right crus of diaphragm. The xiphisternum provides the necessary attachments to the complex system of glossal protrudor and retractor muscles of the tongue. The hyoid bone has a different role than in other mammals,since it helps remove termites and ants from the tongue at the entrance to the esophagus; a transverse fibrous septum in the tongue itself serves for the attachment of lingual muscles. The first 20 cm of the tongue are loosely attached and partly folded in the cervical region. The tongue has a cavernous tissue, also found in other mammals requiring little or no mastication, which may affect or control the level of rigidity of its rostral part. The stomach contains a muscular structure similar in function to a gizzard,filled with small stones (maximum diameter 5 mm), which might contribute to grinding the exoskeleton of prey.
Breeding. Little information exists. Fetuses 24-29 cm long were found in pregnant females from DR Congo in November and December. Gestation may last approximately five months. A single young is born with eyes open and soft, amber-colored scales that harden rapidly; newborns cannot use their legs, but wriggle on their belly. Young start feeding on arthropods at three months, and stay with mother until next birth.
Activity patterns. Solitary, nocturnal, and terrestrial, the Giant Pangolin is a secretive species difficult to survey. During the day, opportunistically rests in burrows, dead and fallen trees, dense vegetation (thickets, piles of plant debris), and simple tunnels dig under ant or termite mounds. The tunnels are used for resting and feeding, and have many openings; the mean depth of the gallery network usually is 50-60 cm. The Giant Pangolin’s gait is an alternated walk with alternative rising of the tail; when the tail is down,it leaves deep drag marks on the ground. May leave numerous footprints along river banks in riparian forests; plantigrade hindfeet leave tracks similar to those of a small elephant. Poor swimmer, crossing streams with body entirely submerged, nose emerging, paddling with feet. Absence of pronosupination in forefeet, but powerful pronation of hindfeet due to a specific muscular flexor, supporting bipedism (although bipedal walk might be less frequent than in the Ground Pangolin, M. temminckii ). Body temperature approximately 34°C during daytime, slightly below the usual mammalian range; may decrease to 26°C when ambient temperature reaches 17°C (under experimental conditions). Tree climbing is feasible, buttail is poorly prehensile and so does not contribute. When in danger, rolls up into a ball, the large tail strongly pressed against face and belly for protection. Tail can also be projected with force towards the source of danger. The powerful forefeet and claws can destroy metal plates and cement walls 3 cm thick.
Movements, Home range and Social organization. Movements of individuals remain unknown. Greater anal gland marking activities in larger males may suggest territoriality and intolerance towards other males. Individuals have been observed regularly from a very restricted area during two years, but home range size and seasonal variation in habitat use are unknown. Given the large size and diet specialization of the species, density per km? is expected to be low.
Status and Conservation. CITES Appendix II. Classified as Near Threatened on The IUCNRed List because assumed to have undergone a decline of 20-25% overthe past 15 years, mainly due to the widespread impact of bushmeat hunting. Some local populations seem stable, however, including those of the Ituri Forest and the Salonga National Park in the DR Congo. Widely distributed, but localized and often rare. Very rarely recorded in international trade. Although strictly protected in several countries, heavily hunted for bushmeat consumption and traditional medicine, a situation aggravated by continuous deforestation of its primary habitat in West and Central Africa. Especially appreciated for its tender dark meat, notably in Central Africa. Believed to have gone extinct in Rwanda. Occupies a particular place culturally with rainforest tribes because of its intermediary status between fish and tetrapods. In north-eastern DR Congo, it is notably celebrated in rites marking transition stages such as men’s circumcision, with initiator’s headdress evoking pangolin scaling. Sacred in eastern DR Congo, where it is killed ritually and revered for having taught humans to roof houses; roofs are built with leaves disposed in a way that looks like pangolin scaling. Could locally be protected as a totemic species, as in Uganda, but such customs tend to disappear.
Bibliography. Botha & Gaudin (2007), Doran & Allbrook (1973), Dupuy (1968), Hatt (1934), Hoffmann (2008b), Jentink (1882), Jones (1973), Jouffroy (1966), Kingdon (1997), Lewis (1991), Pagés (1970), Poche (1973), Sayer & Green (1984).
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
