Suborder:
|
Goniatitina
|
Superfamily:
|
Dimorphoceratoidea
|
Family:
|
Girtyoceratidae
|
Subfamily:
|
Girtyoceratinae
|
Genus:
|
Eumorphoceras
|
Species:
|
bisulcatum mut. beta |
Qualifier:
|
sy |
Author:
|
Schmidt 1934,p.451
|
Valid:
|
Eumorphoceras beta Riley 1987 |
Lower Boundary:
|
DER E2b--E2c(Cravenocerat.--Nuculoceras), 321 million years
|
Upper Boundary:
|
Arnsbergian--Chokierian [ARN--CHO], 319 million years
|