Labidosaurus hamatus (Cope 1895, Case 1911) Artinskian, Early Permian, ~280 mya, ~75 cm in length, was derived from a sister to Eocaptorhinus and was a sister to Captorhinus and Moradisaurus.

Distinct from Eocaptorhinus, the skull of Labidosaurus had a straight and horizontal rostral profile and a deep premaxillary notch greater than 45 degrees. The skull roof was flat. The jawline descended. The ventral naris is bordered chiefly by the maxilla. The frontals were longer than the nasals, as in more basal captorhinids. The paraoccipital angle was 20-40 degrees. The supratemporals were transverse in orientation. The quadratojugal was robust. The teeth retained sharp tips as in more basal taxa. The dentary did not contribute to the coronoid.

Gastralia were present. The scapula and coracoid were subequal in size. The femur and humerus were subequal. All the metacarpals and metatarsals were elongated. All the digits were more gracile. Metatarsal I is longer than 75 percent of mt III and IV. Metatarsal V is the shortest metatarsal.

Moradisaurus grandis (Taquet 1969, Late Permian, skull length 40cm, est 1.8m total length) is the largest captorhinid. Data comes from a skull without a cranial roof and one hind limb with short, robust toes.

Case EC 1911. A revision of the Cotylosauria of North America. Carnegie Institution of Washington Publication 145:1–122.

Cope ED 1895. The Reptilian Order Cotylosauria. Proeedings of the American Philosophical Society 34(149): 436-457

Modesto SP et al. 2007. The skull and the paleoecological significance of Labidosaurus hamatus, a captorhinid reptile from the Lower Permian of Texas. Zoological Journal of the Linneans Society 149(2):237–262.

de Ricqles, A de and Taquet P 1982. La Faune de Vertébrés du Permien Supérieur du Niger I. Le Captorhinomorphe Moradisaurus grandis (Reptilia, Cotylosauria) - Le Crane. Ann. Paléont., 68(1): 33-106.

Taquet P 1969. Première découverte en Afrique d'un Reptile Captorhinomorphe (Cotylosaurien). C. R. Acad. Sc. Paris D, 268(1): 779-781.

wiki/Labidosaurus
wiki/Moradisaurus