| 翻訳と辞書 |
| Guaibasauridae ： ウィキペディア英語版 |
Guaibasauridae
Guaibasauridae is a family of primitive saurischian dinosaurs, known from fossil remains of late Triassic period formations in Brazil and Argentina.
==Classification==
The exact makeup and classification of the Guaibasauridae remains uncertain. The family was originally named by Jose Bonaparte and colleagues in 1999 to contain a single genus and species, ''Guaibasaurus candelariensis''. When a second specimen of ''Guaibasaurus'' was described from better remains in 2007, it became easier to compare it to other enigmatic early saurischians, which are often difficult to classify because they combine characteristics of the two major saurischian groups, Theropoda and Sauropodomorpha. Bonaparte and colleagues, in light of the information gained from this second specimen, found that the genus ''Saturnalia'' (which is anatomically very similar to ''Guaibasaurus'') could also be assigned to the Guaibasauridae, though they did not conduct a phylogenetic analysis or define Guaibasauridae as a clade. The researchers also tentatively assigned the poorly understood genus ''Agnosphitys'' to this family.
Bonaparte and colleagues (2007) found that guaibasaurids have more characteristics in common with theropods than they do with early sauropodomorphs (or "prosauropods"). Because of this, according to Bonaparte, they are most likely either a very basal group on the stem leading toward sauropodomorphs, or a group ancestral to both sauropodomorphs and theropods. Furthermore, the authors interpret this as evidence that the common ancestor of both saurischian lineages was more theropod-like than prosauropod-like.〔
In 2008, Martin Ezcurra defined the subfamily Saturnaliinae for the clade containing ''Saturnalia'' and ''Chromogisaurus'', which were found to be close relatives in several studies.〔Ezcurra, M. D. (2010). A new early dinosaur (Saurischia: Sauropodomorpha) from the Late Triassic of Argentina: a reassessment of dinosaur origin and phylogeny. Journal of Systematic Palaeontology, 8(3), 371-425.〕 While they are sometimes found to be a subgroup of guaibasaurids, other studies have found the saturnaliines to form an independent lineage at the very base of the sauropodomorph family tree.
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「Guaibasauridae」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|