Suborder:
|
Tornoceratina
|
Superfamily:
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Tornoceratoidea
|
Family:
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Tornoceratidae
|
Subfamily:
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Aulatornoceratinae
|
Genus:
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Protornoceras
|
Species:
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subacutum |
Qualifier:
|
sy |
Author:
|
Sobolev 1914,p.360
|
Valid:
|
Protornoceras simplificatum (Sobol.1914) |
Lower Boundary:
|
UD2H--UD2I:(mamilliferum base) [12,90], 370 million years
|
Upper Boundary:
|
P.delph.--low.Platyclym.annulata IIIb/IV, 367.6 million years
|