The Paleocene Teberemt Formation south of the Adrar des Iforas Mountains, between Saguirilidad and In Fargas, Mali, yielded a nearly complete skull of a new genus and species of side-necked turtle, Acleistochelys maliensis. Acleistochelys is a member of the family Bothremydidae Baur, 1891, because: 1 the fossa precolumellaris is absent, 2 the foramen stapedio-temporale faces anteriorly, 3 the eustachian tube is separated from the stapes by bone, and 4 an exoccipital-quadrate contact is present. Within the Bothremydidae, Acleistochelys belongs to the tribe Taphrosphyini because: 1 the maxilla-quadratojugal contact is absent, 2 the palate is dorsally arched, 3 there is only a small contribution of the palatine to the triturating surfaces, and 4 the septum orbitotemporale is at least partially open. Acleistochelys is most closely related to Azabbaremys because both share a narrow vomer lacking a posterior attachment to the palatines.

The specimen was found in a marine limestone associated with crocodiles, echinoids, and mollusks.