Suborder:
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Goniatitina
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Superfamily:
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Gastrioceratoidea
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Family:
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Homoceratidae
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Subfamily:
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Homoceratinae
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Genus:
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Isohomoceras
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Species:
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praematurum |
Qualifier:
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ss |
Author:
|
Haug 1898,p.98
|
Lower Boundary:
|
RUS Nm1c2--Nm2a1, Homoc.-Hudsonoc.GZ, 318.1 million years
|
Upper Boundary:
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RUS Nm2a1--Nm2a2 (H.coronat.--Hu.proteus, 317.7 million years
|