that segnosaurs, prosauropods and ornithischians were each independently derived from early dinosaurs, but found these options unlikely. He considered the common descent of these groups as support for the idea that dinosaurs were a monophyletic (natural) group, which was contested by some paleontologists at the time (who instead thought different dinosaurs groups evolved independently from thecodonts). Paleontologist David B. Norman considered Paul's idea a contentious claim "bound to provoke much argument" in 1985. In 1988, Paul maintained that segnosaurs were late surviving ornithischian-like prosauropods, and proposed a segnosaurian identity for Therizinosaurus. He also placed segnosauria within Phytodinosauria, a superorder that paleontologist Robert Bakker had created in 1985 to retain all plant-eating dinosaurs. In a 1986 study of the interrelationships of saurischian dinosaurs, paleontologist Jacques Gauthier concluded that segnosaurs were prosauropods. While he conceded they had similarities with ornithischians and theropods, he proposed these featured had evolved independently. In a 1989 conference abstract about sauropodomorph interrelationships, paleontologist Paul Sereno also considered segnosaurs as prosauropods, based on skull features. In a 1990 review article, Barsbold and paleontologist Teresa Maryańska found Segnosauria to be a rare and aberrant group of saurischians, in an unresolved position among sauropodomorphs and theropods, probably closer to the former. They therefore listed them as Saurischia sedis mutabilis ("position subject to change"). Though they agreed the hindlimbs assigned to Therizinosaurus in 1982 were segnosaurian, they did not consider this justification for Therizinosaurus itself being a segnosaur, since it was only known from forelimbs. In 1993, paleontologists Dale A. Russell and Dong Zhi-Ming described the new genus Alxasaurus from China, at the time the most complete large theropod from its time and place. While it was similar to prosauropods in some respects, the detailed morphology of its limbs linked it to Therizinosaurus and segnosaurs. Since it preserved both fore and hindlimbs, Alxasaurus showed that Perle's assignment of segnosaurian hindlimbs to Therizinosaurus was probably correct. Russell and Dong therefore proposed that Segnosauridae was a junior synonym of Therizinosauridae (since the latter name was older), with Alxasaurus being the most completely known representative so far, providing a better understanding of the group. They also named the new higher taxonomic rank Therizinosauroidea to contain Alxasaurus and Therizinosauridae (since the new genus was somewhat different from its relatives), which they placed in the group Tetanurae within Theropoda. They considered therizinosaurs most closely related to ornithomimids, troodontids, and oviraptorids, which they placed together in the