Description

Middle Cambrian
Montana, USA

0.6 inch fine. No cheeks.

Trilobite, Arthropod.

This is a specimen for the beginner looking for an affordable example of a trilobite.

Trilobites appeared in the Early Cambrian and became very diverse until a mass extinction event at the end of the period nearly wiped them out.  They recovered during the Ordovician but suffered greatly during another mass extinction event at the end of that period.  A third but less diverse wave of trilobites appeared in the Devonian but the mass extinctions at the end of the period nearly eliminated the whole group again.  They survived into the Carboniferous and Permian but became rare.  They died out during the end-Permian mass extinction.