Fauna of the Vale and Choza : Pelycosauria : family Caseidae

Abstract

Class REPTILIA Subclass Eureptilia Infraclass Synapsida Order Pelycosauria Suborder Edaphosauria Family Caseidae Casea Williston This genus has been known heretofore only from a single species, Casea broilii Williston (Williston, 1910). The type of the species and all referred specimens have come from a single concentration, the Cacope bone bed in western Baylor County, Texas. The horizon in which this bone bed was found generally has been considered to be Arroyo in age (see, for example, Romer and Price, 1940), but my recent stratigraphic studies of the complete Clear Fork section have led me to the conclusion that it actually should be placed in the lower Vale. Collections made from the Vale and Choza over the past several years include three specimens of Casea, two from a single nodule in the upper Vale and one from the middle Choza. The other described genera of the family Caseidae are Cotylorhynchus Stovall (1937) from the Hennessey Formation of Oklahoma and San Angelo Formation of Texas, and Caseoides and Angelosaurus from the San Angelo (Olson and Beerbower, 1953). As yet undescribed caseids have recently been found in the Flower Pot Formation. The only other specimen identified as a caseid---one in the collections of the University of California at Berkeley--- consists of a skull from the Abo Formation of New Mexico and appears to be a very primitive member of the family, according to a personal communication from Wann Langston of the University of California. The family had a long history and was in existence during the time of deposition of the beds of the Wichita group and the Clyde and Arroyo formations of the Clear Fork group in Texas, Intensive work by various collectors has not revealed any trace of it in the Texas area prior to the lower Vale, Presumably members of the family did not penetrate the part of the Permian delta represented by the Texas deposits until after the deposition of the Arroyo Formation,