翻訳と辞書 Words near each other ・ Uromyces ciceris-arietini ・ Uromyces dianthi ・ Uromyces euphorbiae ・ Uromyces graminis ・ Uromyces inconspicuus ・ Uromyces lineolatus subsp. nearcticus ・ Uromyces medicaginis ・ Uromyces musae ・ Uromyces oblongus ・ Uromyces pisi-sativi ・ Uromyces proëminens var. poinsettiae ・ Uromyces trifolii-repentis var. fallens ・ Uromyces viciae-fabae var. viciae-fabae ・ Uromycladium ・ Uromyias ・ Urocordylidae ・ Urocordylinae ・ Urocordylus ・ Urocortin ・ Urocortin II ・ Urocortin III ・ Urocotyledon ・ Uroctea ・ Uroctea durandi ・ Urocyclidae ・ Urocyclus ・ Urocyon ・ Urocyon progressus ・ Urocystales ・ Urocystis Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Urocordylidae ： ウィキペディア英語版 Urocordylidae The Urocordylidae are an extinct family of nectridean lepospondyl amphibians. Urocordylids lived during the Late Carboniferous and Early Permian in what is now Europe and North America and are characterized by their very long, paddle-like tails. In life, they were probably newt-like and aquatic. Fossils have been found from Ireland, France, and the eastern United States. The family was named by English naturalist Richard Lydekker in 1889 and includes the well-known genera ''Urocordylus'' and ''Sauropleura'', as well as several others based on less-complete material. The Urocordylidae family is divided into two subfamilies, the Urocordylinae and the Sauropleurinae. The two groups are distinguished by the shapes of their skulls; urocordylines have short, blunt skulls, and sauropleurines have longer, pointed skulls. ==Description== Urocordylids are distinguished by their elongated tails. Each tail vertebra has an upper crest of bone called a neural arch and a lower crest called a haemal arch, and each of these arches is square-shaped and laterally compressed (flattened side-to-side). These arches give the tails of urocordylids a paddle-like shape. The urocordylids ''Sauropleura'' and ''Crossotelos'' have holes in their tail vertebrae that are thought to have served as passageways for spinal nerves, an unusual feature given that spinal nerves pass between successive vertebrae in most vertebrates. Salamanders also have spinal nerves passing through their vertebrae, although the holes are in different positions and do not indicate a close evolutionary relationship with urocordylids.〔 Another distinguishing feature of urocordylids is the loose connection between the bones of the skull. The bones at the back of the lower jaw do not connect with the rest of the skull. Instead, a gap extends across the skull and closes in front of the eye sockets. This allows the upper jaw to flex upward, increasing the gape of the mouth. The bones at the back of the jaw may also be able to flex outward.〔 The flexibility of the jaws of urocordylids may have been an adaptation for feeding, allowing sharp teeth at the tip of the jaw to face outward so prey could be more easily captured.〔 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「Urocordylidae」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.