Suborder:
|
Anarcestina
|
Superfamily:
|
Triainoceratoidea
|
Family:
|
Pharciceratidae
|
Genus:
|
Extropharciceras
|
Species:
|
arenicum |
Qualifier:
|
ss |
Author:
|
Petter 1959,p.138
|
Lower Boundary:
|
FRM P.lunulicosta--Pharciceras arenicum, 386.6 million years
|
Upper Boundary:
|
FRM Pharc.arenicum--Pseudoprobel.pernai, 386.2 million years
|