Suborder:
|
Goniatitina
|
Superfamily:
|
Neoglyphioceratoidea
|
Family:
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Cravenoceratidae
|
Subfamily:
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Cravenoceratinae
|
Genus:
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Cravenoceras
|
Species:
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ningxiaense |
Qualifier:
|
ss |
Author:
|
Gao 1983,p.467
|
Lower Boundary:
|
RUS Nm1a1 base, Hypergon.-Ferganoc. GZ, 327.8 million years
|
Upper Boundary:
|
RUS Nm1b2--Nm1c1,Fayettevillea-Delepinoc, 324 million years
|