Type
Zone
Age range
295–294.1 Ma
Cisuralian
Asselian
Sweetognathus binodosus
Sweetognathus merrilli-Mesogondolella uralensis
Streptognathodus postfusus
295.0294.9294.9294.9294.8294.8294.7294.6294.6294.6294.5294.4294.4294.4294.3294.3294.2294.1294.1