Suborder:
|
Goniatitina
|
Superfamily:
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Schistoceratoidea
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Family:
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Schistoceratidae
|
Genus:
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Trettinoceras
|
Species:
|
ellesmerense+ |
Qualifier:
|
ss |
Author:
|
Nassichuk 1975,p.137
|
Lower Boundary:
|
U Morrowan (Bloydian)--Atokan[MOR--ATO], 310.4 million years
|
Upper Boundary:
|
U Atokan--Desmoinesian [ATO--DES], 308.6 million years
|