more clear. This new taxon represented the most complete member and was known from multiple specimens with numerous theropod traits. Moreover, the preserved hindlimbs in some specimens showed that the assignment of segnosaurian hindlimbs to Therizinosaurus was correct and "segnosaurs" were in fact theropods. Russell and Dong also noted the extreme similarities between Therizinosauridae and Segnosauridae and considered that the latter was a synonym of the former due to priority. However, Alxasaurus was a fairly more primitive genus and the superfamily Therizinosauroidea was coined to contain it and related species. Posterior to this year, Clark and colleagues redescribed the holotype skull of Erlikosaurus and found more theropod traits than when first described. They concluded that therizinosaurs were more likely to be classified as maniraptoran theropods. Therizinosauria itself, was erected in 1997 by Rusell in order to contain all of these theropods. This new infraorder was composed of Therizinosauroidea and the more advanced Therizinosauridae. The family Therizinosauridae was first given a phylogenetic definition by Paul Sereno in 1998, who defined it as all dinosaurs closer to Erlikosaurus than to Ornithomimus. In 2010, Lindsay Zanno conducted the most detailed phylogenetic analysis of the Therizinosauria to that point. She cited the inaccessibility, damage, potential loss of holotype specimens, scarcity of cranial remains, and fragmentary specimens with few overlapping elements as the most significant obstacles to resolving the evolutionary relationships within the group. The position of Segnosaurus and those of some other Asian therizinosaurids was affected by these factors; Zanno stated more well-preserved specimens and the rediscovery of missing elements would be necessary. Zanno also revised Therizinosauroidea to exclude Falcarius and retained it in the wider clade Therizinosauria, which became the senior synonym of Segnosauria. In addition, she defined Therizinosauridae as the least inclusive clade containing Erlikosaurus, Nothronychus, Segnosaurus and Therizinosaurus. Falcarius and Jianchangosaurus are now regarded as the most primitive therizinosaurs while therizinosauroids are considered to be more derived that these two taxa, but less derived than therizinosaurids. Most phylogenetic analyses recover the family Therizinosauridae containing Erlikosaurus, Erliansaurus, Nanshiungosaurus, Neimongosaurus, Nothronychus, Segnosaurus and Therizinosaurus. However, Suzhousaurus is commonly recovered within the group. Therizinosauridae, along a handful of named genera, constitute the superfamily of Therizinosauroidea and finally, Therizinosauroidea falls within the higher infraorder of Therizinosauria. Although a consensus has yet to be reached, it has been proposed that therizinosaurs are the most primitive clade within Maniraptora, as well as the sister clade to oviraptorosaurs.