Type
Zone
Age range
468.7–467.4 Ma
Middle Ordovician
Darriwilian
Histiodella sinuosa
Histiodella altifrons
Microzarkodina flabellum/Tripodus laevus
468.7468.6468.5468.4468.3468.2468.1468.0467.9467.8467.7467.6467.5467.4