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''Styloichthys'' (Greek: ''stylo'' "pillar" and ''ichthys'' "fish"; "Pillar fish") is a prehistoric sarcopterygian, lobe-finned fish which lived during the Early Devonian (Lochkovian) period of East Yunnan, South China. Because it is clear that the jaws and skull of ''Styloichthys'' share many derived features with coelacanthiformes〔 〕 it is placed as the oldest coelacanth. ==Description== ''Styloichthys'' is characterized by large pores on the cosmine surface. These pores are often spoon-shaped and arranged in parallel grooves. There is a jagged margin between ethmosphenoid and otoccipital shields, an otoccipital with a wide flat surface carrying no vestibular fontanelle. The snout bends sharply downward and is slightly concave. The lower jaw has a ventrally protruding flange formed by prearticular and meckelian bone. Also characteristic of ''Styloichthys'' is the lyre-shaped trajectory of the supraorbital canal, a fenestra ventralis, small internasal cavities, three coronoids in the lower jaw, an eyestalk and a slender postorbital pila which connects the basipterygoid process and the side of the braincase wall. 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「Styloichthys」の詳細全文を読む スポンサード リンク
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