Peters, 1854
Zambezi flapshell turtle
Recognition
The oval carapace (to 56 cm) is greenish and may contain faint blotches. In adults, it is smooth and keelless; in juveniles, it is roughened by a vertebral keel and numerous longitudinal rows of small tubercles. The carapace is less anteriorly protruding than in its congener, Cycloderma aubryi. No prenuchal bone is present. A preneural and a neural separate the 1st pleurals; seven or eight neurals are present, usually forming a continuous series. There are eight pairs of costals; the 7th and 8th pair, or only the 8th, touch medially. All carapacial bones are covered with fine granulations. The adult cream-colored plastron has faded gray blotches. There are seven plastral callosities; those over the entoplastron are very small. The epiplastra are large ovals which touch medially. The entoplastron has the posterior prong inserted into a notch on the anterior border of the fused hyo-hypoplastra. The hyo-hypoplastra are widely separated medially, and the xiphiplastra are short with medially touching callosities. The skull is depressed with a bony snout equal in length to the greatest diameter of the orbit. The interorbital width is about 50% of the height of the orbit. Premaxillae are usually absent; when present, small and scalelike. The prefrontals touch the vomer, if it is present, and the jugal enters the orbital rim. The mandible lacks a symphysial ridge; the symphysial width is less than the greatest diameter of the orbit. The head is gray to green with five longitudinal black stripes beginning on the crown and sides behind the orbits and running backward onto the neck. The chin and throat are either immaculate white or contain some dark streaks. Limbs are grayish green. Four or five antebrachial scales occur on the upper surface of each forefoot.
Males have longer, thicker tails than do females.
Distribution
Cycloderma frenatum occurs in East Africa from the Rufiji river basin in Tanzania to the Save river basin in Mozambique and southeastern Zimbabwe.
Habitat
Cycloderma frenatum lives in streams, rivers, lakes, and ponds, in both flowing and stagnant waters.
Natural History
Nesting occurs from December to March. Loveridge and Williams (1957) reported females oviposited after rains following an 8-month drought. Clutches normally include 15-25 brittle-shelled, spherical eggs about 30-35 mm in diameter. Hatchlings have been found from December to February. Their carapace lengths range from 40 to 48 mm (Loveridge and Williams, 1957), and they are colored and patterned like the adults, but brighter.
C. frenatum is carnivorous, feeding on fish, aquatic snails, mussels, and possibly amphibians. Sachsse (1971) reported this species not only ambushes fish (like Chitra indica), but also, if necessary, will pursue it over short distances.
These turtles are shy and withdraw into the shell when disturbed. Much of their lives is spent buried beneath mud or sand.
IUCN Red List Status (1996)
Lower risk: near threatened.