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Rhabdodontids were herbivorous ornithopod dinosaurs from the Cretaceous Period. Rhabdodontids were similar to large, robust "hypsilophodonts", with deep skulls and jaws. The family was first proposed by David B. Weishampel and colleagues in 2002. The rhabdodontids were defined as "the most recent common ancestor of ''Zalmoxes robustus'' and ''Rhabdodon priscus'' and all the descendants of this common ancestor". In 2005, Paul Sereno defined the family as "the most inclusive clade containing ''Rhabdodon priscus'' but not ''Parasaurolophus walkeri''".〔Sereno, P.C. (2005). "Stem Archosauria Version 1.0." ''TaxonSearch''. Available: (http://www.taxonsearch.org/Archive/stem-archosauria-1.0.php ) via the Internet. Accessed 24 November 2010.〕 The Rhabdodontidae includes the type genus ''Rhabdodon'', ''Zalmoxes'', ''Mochlodon'' and possibly ''Muttaburrasaurus''.〔McDonald, A.T., Kirkland, J.I., DeBlieux, D.D., Madsen, S.K., Cavin, J., Milner, A.R.C. and Panzarin, L. (2010). "New Basal Iguanodonts from the Cedar Mountain Formation of Utah and the Evolution of Thumb-Spiked Dinosaurs." ''PLoS ONE 5'', 11: e14075. PMID 21124919〕 Rhabdodontid fossils have been found in Europe and Australia in formations dating from the Early to Late Cretaceous, 100 to 66 million years ago. Ősi ''et al.'' (2012) proposed that ''Rhabdodon'' underwent gigantism on the mainland, as opposed to ''Zalmoxes'' and ''Mochlodon'' experiencing nanism on island habitats. In 2013, Darren Naish discovered a tiny rhabdodont tibia from Sebeș, Romania, turning out to be the smallest known; a paper (Brusette et ''al'' 2013.) later in the same year identified it as ''Zalmoxes'', cf. ''Z. shqiperorum''.〔Brusette et al (2013): AN INFANT ORNITHOPOD DINOSAUR TIBIA FROM THELATE CRETACEOUS OF SEBEŞ, ROMANIA〕 ==Classification== The Rhabdodontidae are a group of ornithopod dinosaurs, more specifically some of the basalmost iguanodonts. Most analyses find them to be more derived then ''Tenontosaurus'' but more basal then Elasmaria, Dryosauridae, ''Camptosaurus'', and more advanced Iguanodonts. There are differing opinions as to the constituents of Rhabdodontidae. The original definition, the last common ancestor of ''Zalmoxes robustus'' and ''Rhabdodon priscus'', would not include ''Muttaburrasaurus''. The definition by Sereno, the most inclusive clade containing ''Rhabdodon priscus'' but not ''Parasaurolophus walkeri'', would include the entire ghost lineage, and ''Muttaburrasaurus''. This ghost lineage lasts 90 million years without ''Muttaburasaurus''. Most phylogenetic analyses recover ''Zalmoxes'' and ''Mochlodon'' to be sister taxa, with ''Rhabdodon'' as the sister taxon to that (Ősi et al. 2012; McDonald 2012a).〔〔 Multiple analyses also find ''Muttaburrasaurus'' to be the sister taxon to all other rhabdodontids, including McDonald (2012a), and McDonald ''et al.'' (2010).〔〔 The left genus-level cladogram is from an analysis by McDonald ''et al.'' (2010), including all possible rhabdodontids:〔 The right cladogram shows a Rhabdodontidae not including ''Mochlodon'', found by McDonald (2012a):〔 } }} }} | align="left" width="50%"| }} }} | align="right" width="50%" | |} The left cladogram is from Osi ''et al.'' (2012) and excludes ''Muttaburrasaurus'' from Rhabdodontidae:〔 The right cladogram is from Weishampel ''et al.'' (2003) and excludes ''Mochlodon'' and ''Muttaburrasaurus'' from Rhabdodontidae: } }} }} }} }} | align="right" width="50%" | }} }} }} }} |} 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Rhabdodontidae」の詳細全文を読む スポンサード リンク
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