(Duméril, 1856)
African forest turtle
Recognition
The oval carapace (to 30 cm) is flattened dorsally and bears a low medial keel which may disappear with age. All five vertebrals are broader than long, with the 1st the broadest and the 4th and 5th the narrowest. X-rays of the carapaces of several individuals showed a continuous series of eight neural bones with the 1st touching or nearly touching the nuchal bone, and the reduced 8th neural widely separated from the suprapygal. There is no cervical scute, but there are 11 pairs of marginals. The marginals are not posteriorly serrated in adults, but may be slightly so in juveniles. P. gabonensis is easily separated from other species of Pelusios by its carapacial coloration and pattern. It is buff to gray yellow with a distinct black vertebral stripe which widens on the anterior marginals. The carapace has a tendency to darken with age by adding black radiations to the scutes until, in very old and large individuals, it may become almost totally black. The large plastron covers almost all of the carapacial opening, and is posteriorly notched. Its anterior movable lobe is long, and the abdominal scute short (less than half as long as the anterior lobe). The plastral formula is: hum > fem > an >< intergul > abd > pect > gul. Plastron and bridge are black with light-yellow seams. The head is moderately broad with a protruding snout and a slight notch, flanked by two toothlike cusps on the upper jaw. Two barbels are present on the chin. The head is buff colored with a broad, black Y-shaped stripe connecting the orbits and extending backward medially onto the neck. A second dark stripe may extend between the orbit and tympanum. Jaws and throat are tan in adults, but black in juveniles. Large, irregularly shaped scales occur on the anterior surfaces of the forelimbs. Limbs are blackish in juveniles, but gray to yellow in adults.
Males have slightly concave plastra, while those of females are flat. The male's tail is much longer and thicker than that of the female.
Distribution
Pelusios gabonensis lives in tropical West Africa where its range extends from northern Angola and western Tanzania northwestward to Liberia and Guinea.
Habitat
This terrapin is confined to tropical rain forests where it inhabits marshes, swamps, streams, and probably deeper rivers. The young prefer quiet waters but the adults are found in flowing waters.
Natural History
Cansdale (1955) reported they lay about a dozen eggs in a nest dug close to the water. Ewert (1979) reported the average carapace length of eight hatchlings was 42.3 mm, and Schmidt (1919) found a juvenile of 42 mm with yolk sac and egg tooth (caruncle) still present, but no hinge on the plastron. The young have darker skin than adults, and also a distinct keel on the carapace.
Pelusios gabonensis is carnivorous, feeding on insects, worms, snails, and fish; it is attracted to traps baited with fish.
IUCN Red List Status (1996)
Not listed.