Suborder:
|
Goniatitina
|
Superfamily:
|
Neoglyphioceratoidea
|
Family:
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Cravenoceratidae
|
Subfamily:
|
Cravenoceratinae
|
Genus:
|
Cravenoceras
|
Species:
|
subinvolutum |
Qualifier:
|
sy |
Author:
|
Librovitch 1938,p.64
|
Valid:
|
Cravenoceras arcticum Librovich 1938 |
Lower Boundary:
|
RUS Nm1a2--Nm1b1,Uralopron.-Cravenoc. GZ, 326.4 million years
|
Upper Boundary:
|
RUS Nm1b1--Nm1b2 (Domb.carinat.--tectus), 324.6 million years
|