TaxNo: 2498Beyrichoceras tardum
| Suborder: |
Goniatitina
|
| Superfamily: |
Pericycloidea
|
| Family: |
Maxigoniatitidae
|
| Genus: |
Beyrichoceras
|
| Species: | tardum |
| Qualifier: | ss |
| Author: |
Ruzhencev 1966,p.53
|
| Lower Boundary: |
Up.Visean Goniatites BZ base [up.VIS], 333.5 million years
|
| Upper Boundary: |
DER Go beta striatus--Go beta falcatus, 329.4 million years
|