Kinixys erosa

(Schweigger, 1812)
Serrated hinge-back tortoise

The elongated carapace (to 32.3 cm) is domed with a flat, unkeeled dorsal surface, sloping sides, the anterior marginals flared and reverted, and the posterior marginals only slightly flared but strongly serrated and reverted. A shallow depression occurs in the cervical region, and the posterior portion of the carapace slopes to the rear, but does not drop off nearly as abruptly as in K. homeana, and the sloping begins at the middle of the 5th vertebral. A cervical scute is only rarely present. All vertebrals are broader than long; the 5th is flared and widest. There are 11 or sometimes 12 marginals on each side, and the supracaudal is not divided. Carapacial color ranges from totally dark brown to dark brown with yellow to orange centers on all scutes. Occasionally a band of yellow occurs along the base of the pleurals. The thickened, paired gulars project anteriorly beyond the carapacial rim, especially in males, and are notched in front. The short plastral hindlobe may lack a posterior notch or be shallowly notched. There are three or four small axillary scutes and one large inguinal (in contact with the femoral) on each bridge. The plastral formula is: abd > hum >< gul >< pect > fem >< an. The plastron is dark brown to black with some yellow along the seams. The head is small to moderate with a nonprojecting snout and a hooked upper jaw. Its prefrontals are divided longitudinally, the large frontal may be subdivided, and the rest of the head scales are small and irregularly shaped. The head varies from brown to yellow, but usually has some yellow pigment. Each forelimb has on its anterior surface a few large, sometimes overlapping scales in four or five longitudinal rows. Each thigh lacks enlarged tubercles and the heel usually has no spurlike enlarged scales. Five claws are present on each forefoot. Limbs and tail are brown. The tail ends in a clawlike tubercle.
Males have longer, thicker tails and more projecting gulars than do females, and concave plastra.

Kinixys erosa ranges in West Africa from Gambia eastward to the Democratic Republic of Congo and Uganda, and south to Cabinda and southern Angola.

This hinge-back is a forest dweller and seems to prefer moist areas, such as marshes, river banks, and bottom wetlands. It is often found resting in the water and is a fair swimmer. When on land it spends much time buried beneath roots, logs, and plant debris (Schmidt, 1919).

Natural History
Blackwell (1966) observed a mating attempt on 9 April in Nigeria. The male approached from the side and pushed the female's carapace until he could bring the cloacae together. He emitted a series of hissing squeaks near the end of copulation. Eggs are laid in the ground and covered with leaves.
One to four oval (40-46 x 31-38 mm), brittle-shelled eggs are laid at one time. A juvenile thought to be a hatchling by Blackwell (1966) was 40 mm long. The young are usually unicolored brown with flattened, very spiny-rimmed carapaces which lack the hinge.
Kinixys erosa is omnivorous, feeding on plants, fruits, small invertebrates and carrion. Eglis (1962) described olfactory, food-exploratory motions as straightforward and not exaggerated.

IUCN Red List Status (1996)
Data deficient.