(Schweigger, 1812)
Adanson's mud turtle
Recognition
The carapace (to 18.5 cm) is elliptical, being broader posteriorly than anteriorly, and flattened across the vertebrals. A low medial keel is present on the first four vertebrals; all five vertebrals are broader than long in juveniles, but lengthen with age until they are of equal dimensions or slightly longer than broad. The 4th is the smallest. Seven or eight neurals may be present; if only seven, the 1st is missing. There is no cervical scute. The posterior marginal border is smooth and rounded. In color, the carapace is yellow brown to gray brown; some also have darker radiations or spots on the scutes. The plastron is smaller than the carapace and cannot completely cover the limbs when closed. Its anterior lobe is long and rounded, usually well over twice as long as the length of the abdominal scute. The posterior lobe is more tapered and contains a deep anal notch. Mesoplastra are only medially tapered posteriorly, forming a straight transverse hinge along the hyoplastra. The plastral formula is: fem > abd >< hum > intergul > an > pect >< gul. The intergular is about twice as long as broad. Both the pectoral and abdominal scutes contribute to the bridge, and axillary and inguinal scutes are normally absent. Both plastron and bridge are yellow. The broad head has a short, only slightly projecting snout, and an upper jaw lacking either a hook or a notch. The frontal scale is very large. There is a pair of pronounced chin barbels. The head is gray brown dorsally with yellow vermiculations, and yellowish posteriorly. A yellow stripe may extend from the orbit to the tympanum. The jaws are yellow and other skin is yellow brown.
Males have long, thick tails; females have short tails.
Distribution
The range of Pelusios adansonii extends from the White Nile in the Sudan westward through Chad to Cameroon, Nigeria, Mali, Liberia, Senegal, and Gambia.
Habitat
This is a river turtle of savannah regions outside of the rainforest (Loveridge, 1941).
Natural History
Werner (in Loveridge, 1941) dissected a female along the White Nile in March which contained seven eggs that measured from 29.5 x 18 to 33 x 19 mm. Ewert (1979) described the eggs as ellipsoidal with hard, expansible shells.
Pelusios adansonii is carnivorous and will take fish and a variety of meats in captivity.
IUCN Red List Status (1996)
Not listed.