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Suborder:
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Goniatitina 
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Superfamily:
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Dimorphoceratoidea 
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Family:
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Dimorphoceratidae 
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Subfamily:
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Dimorphoceratinae 
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Genus:
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Dimorphoceras 
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Species:
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rileyi | 
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Qualifier:
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ss | 
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Author:
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	Korn, D & Titus, A 2011, p. 154	 
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Lower Boundary:
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Up.Visean  Goniatites BZ base [up.VIS], 333.5 million years
 
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| 
Upper Boundary:
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Asbian--Brigantian [P1a--P1b] [ASB--BRI], 332 million years
 
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