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''Itagnostus'' is a genus of trilobite restricted to the Middle Cambrian. Its remains have been found in Asia, Australia, Europe, and North America. == Distribution == * ''Itagnostus elkedrensis'' occurs in the Middle Cambrian of Australia (''Ptychagnostus praecurrens''-zone, ''Xystridura templetonensis''-zone, and ''Dinesus''-stage, Elkedra; ''Triplagnostus gibbus''-zone, Sandover Beds; both Northern Territory), the Russian Federation (''Kounamkites''-zone, Nekekit River; ''Liostracus allachjunensis''-zone, Lena River). * ''Itagnostus comis'' is found in the Middle Cambrian of Australia (''Triplagnostus gibbus''-zone, Sandover Beds, Northern Territory). * ''Itagnostus gaspensis gaspensis'' is reported from the Middle Cambrian of the United States (Geddes Formation, Nevada; ''Ptychagnostus atavus''-zone, Wheeler Formation, Drum Mountains, Utah), Canada (upper part, Grosses Roches, St. Laurence, Quebec), Russian Federation (''Tomagnostus fissus''-zone, Lena River). * ''Itagnostus gaspensis taitzuhoensis'' has been excavated from the Middle Cambrian of Antarctica (lower part, Shackleton Mountains), Australia (''Ptychagnostus praecurrens''-zone, Elkedra, Northern Territory), North-China (''Bailiella''-''Lioparia''-zone, Hsuchang Formation). * ''Itagnostus interstrictus interstrictus'' is present in the Middle Cambrian of Canada (''Ptychagnostus punctuosus''-zone, Cow head Group, Newfoundland), the United States (''Bolaspidella'' (''P. atavus'')-zone, Tatonduk River, Hillard Peak, Alaska; lower part of the ''Bolaspidella''-zone, Western-Utah; Wheeler Shale, Antelope Spring, House Range, Utah), the Russian Federation (Malokuonamsky Horizon, ''Tomagnostus fissus''-zone, and ''Liostracus allachjunensis''-zone, all Lena River). * ''Itagnostus krusei'' is found in the Middle Cambrian of the Russian Federation (''Kounamkites''-zone, Lena River). * ''Itagnostus oepiki'' has been collected in the Middle Cambrian of Australia (''Triplagnostus gibbus''-zone, Sandover Beds; ''Xystridura templetonensis''-zone, Elkedra; both Northern Territory). * ''Itagnostus walleyae'' is reported from the Middle Cambrian of Australia (''Ptychagnostus praecurrens''-zone, Elkedra, Northern Territory). * ''Itagnostus sp.'' has been collected in the Middle Cambrian of the Russian Federation (''Liosttracus allachjunensis''-zone, Lena River).〔 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「Itagnostus」の詳細全文を読む スポンサード リンク
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