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''Guiyu oneiros'' is the earliest articulated bony fish discovered. The generic name ''Guiyu'' is a transliteration of the Mandarin 鬼魚 ''guǐyú'' "ghost fish" and the specific name ''oneiros'' is from Greek ὄνειρος "dream". Fossils of ''Guiyu'' have been found in what is now Qujing, Yunnan, China, in a late Silurian marine strata, about 419 million years old. ''Guiyu'' remains have been found articulated, missing only the caudal fin. The living fish is estimated to have been 33 cm long.〔http://palaeoblog.blogspot.com/2009/03/guiyu-oldest-articulated-osteichthyan_26.html〕〔http://spanish.china.org.cn/science/txt/2009-03/27/content_17510458.htm〕 ''Guiyu'' is described by Chinese palaeontologist Min Zhu and others in 2009, based on a near-complete articulated specimen. It was described as a basal lobe-finned fish with anatomical features of both ray-finned and lobe-finned fishes, although, analysis of the totality of its features place it closer to the class Sarcopterygii (lobe-finned fishes).〔http://scienceblogs.com/pharyngula/2009/04/guiyu_oneiros.php〕 ''Guiyu'' sheds light on the early diversification of bony fishes. This clade, the osteichthyans, splits in two clades: the lobe-finned and the ray-finned (Actinopterygii) fishes. According to new data from ''Guiyu'', this split occurred no later than 419 million years ago, during the early Devonian period. ''Guiyu'' had spine-bearing pectoral girdle, a feature which can be found in primitive gnathostome vertebrates. Other early bony-fish with remarkable features include ''Andreolepis'', ''Lophosteus'', ''Psarolepis'', ''Ligulalepis'' and ''Dialipina''. ''Guiyu'' is part of the Xiaoxiang fauna which is rich in fossils representing a marine ecosystem. Found in the late Ludlow-aged Kuanti Formation, the remains were dated using conodonts as index fossils. The Xiaoxiang fauna also includes galeaspids, placoderms and acanthodians. ==Classification== Cladogram after the analysis of Yu et. al (2010): |1= |1= }} }} }} }} }} 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「Guiyu oneiros」の詳細全文を読む スポンサード リンク
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