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Suborder:
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Goniatitina
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Superfamily:
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Schistoceratoidea
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Family:
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Schistoceratidae
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Genus:
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Paraschistoceras
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Species:
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optatum |
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Qualifier:
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ss |
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Author:
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Ruzhencev 1950,p.122
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Lower Boundary:
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RUS lower--upper Zhigulian, 305.9 million years
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Upper Boundary:
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Gzhelian--Asselian [C--P], 299 million years
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