The name "Paluxysaurus" was based on the specimen FWMSH 93B-10-18, a partial skull including an associated left maxilla, nasal, and teeth. Other bones from the quarry included a partial neck of seven vertebrae, thirteen vertebrae from the back and 30 from the tail, and examples of all limb and girdle bones except some hand and foot bones. It was distinguished from all other sauropods by vertebral details, and has various morphological differences in other bones compared to other sauropods of the Early Cretaceous of North America. The genus was limited to the bonebed remains; for example, the partial skeleton from Wise County known as "Pleurocoelus" sp. (SMU 61732) is not referred to "Paluxysaurus"; instead that specimen is the holotype of "Astrophocaudia slaughteri" D'Emic 2012, another somphospondylan sauropod. There are differences in the remains of "P." sp. and "Paluxysaurus", but they cannot be distinguished with confidence. In 2012, re-analysis of these specimens in light of additional "Sauroposeidon" remains led paleontologists D'Emic and Foreman to conclude that "Paluxysaurus" was the same animal as "Sauroposeidon", and thus a junior synonym of "S. proteles".