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Subject: new LARGE Chinese dinosaur with fibrous integments Date: Thu, 27 May 1999 11:54:00 -0700 From: Betty Cunningham <bettyc@flyinggoat.com> Newsgroups: sci.bio.paleontology, alt.dinosaur (reposted from the dinosaur mailing list with minor edits from an original post by Ralph Miller III-sorry Ralph) The May 27, 1999 issue of _Nature_ features the above named paper, authored by Xing Xu, Zhi-Lu Tang, and Xiao-Lin Wang, which describes a therizinosauroid specimen, named _Beipiaosaurus inexpectus_, which is estimated to have a length (in life) of 2.2 meters, and which features the remains of integumentary filaments resembling those of _Sinosauropteryx prima_, which are up to 70 mm in length (the average fiber length being 50 mm). The specimen, which was discovered in 1996, is far from complete, but contains a number of articulated bone pieces. Quoting the first paragraph posted at <www.nature.com>: "A therizinosauroid dinosaur with integumentary structures from China Xing Xu, Zhi-Lu Tang, & Xiao-Lin Wang Therizinosauroidea ('segnosaurs') are a little-known group of Asian dinosaurs with an unusual combination of features that, until recently, obscured their evolutionary relationships. Suggested affinities include Ornithischia, Sauropodomorpha, Theropoda, and Saurischia _sedis mutabilis_. Here we describe a new therizinosauroid from the Yixian formation (Early Cretaceous, Liaoning, China). This new taxon provides fresh evidence that therizinosauroids are nested within the coelurosaurian theropods. Our analysis suggests that several specialized therizinosauroid characters, such as the Sauropodomorpha-like tetradactyl pes, evolved independently within this group. Most interestingly, this new dinosaur has integumentary filaments as in _Sinosauropteryx_. This indicates that such feather-like structures may have a broad distribution among non-avian theropods, and supports the hypothesis that the filamentous integumentary structures may be homologous to the feathers of birds. Dinosauria Owen 1842 Theropoda Marsh 1881 Coelurosauria _sensu_ Gauthier 1986 Therizinosauroidea Russell and Dong 1993 _Beipiaosaurus inexpectus_ gen. et sp. nov. Etymology. Beipiao: the city near the locality where the specimen was found; saurus: lizard; inexpectus: referring to the surprising features in this animal. Holotype. IVPP V11559 (Institute of Vertebrate Paleontology & Paleoanthropology, Beijing, China; see Fig.1)." End quote. The reference is as follows: XING XU et al: A therizinosauroid dinosaur with integumentary structures from China_Nature_ 399, 350-354 (1999) _Letters to Nature_ A character matrix and list for phylogenetic analyses is available on-line to subscribers as a supplement to the paper. (The paper is likewise available on-line to subscribers at this time). -- ※ 發信站: 批踢踢實業坊(ptt.twbbs.org) ◆ From: 140.112.65.92