Claudiosaurus (claudus is Latin for 'lameness' and saurus means 'lizard') is an extinct genus of diapsid reptiles from the Late Permian Sakamena Formation of the Morondava Basin, Madagascar.

[7] Claudiosaurus is generally assumed to have been an amphibious animal, using its limbs for propulsion, though it was still likely capable of walking on land, and the skeleton shows only limited adaptations to aquatic life.

[11] The Lower Sakamena Formation was deposited in a wetland environment situated within a North-South orientated rift valley, perhaps similar to Lake Tanganyika.

[12] Flora from the formation includes the equisetalean Schizoneura, the glossopterid gymnosperm Glossopteris, and seed fern Lepidopteris.

Other vertebrates known from the Lower Sakamena Formation include the palaeoniscoid fish Atherstonia, the procolophonid parareptile Barasaurus, the gliding weigeltisaurid reptile Coelurosauravus, the neodiapsids Hovasaurus, Thadeosaurus, and Acerosodontosaurus, fragments of rhinesuchid temnospondyls, an indeterminate theriodont therapsid and the dicynodont Oudenodon.