Procambarus primaevus
Crustacean
Early Eocene
Green River Formation
Kemmerer, Wyoming, USA

54mm freshwater crayfish on 62mm slab.

Arthropod. Crustacean.

Procambarus is a genus of freshwater crayfish – a group with a spotty fossil history. P. primaevus is actually one of the first invertebrates ever described from the Green River sandwich beds.  The genus still lives today in North and Central America, preferring warm, slow-moving river, stream, or marsh habitats.

Here’s an affordable specimen for the novice looking for odd arthropods.