Portunus pankowskiorum
Miocene
Monterey Formation
Santa Barbara County CA USA.

33mm carapace on 68mm slab.

Crustacean.  Arthropod.

Portunus is a genus of crab that appeared during the Middle Eocene and still lives today.  Fossil specimens have been found in the United States, Mexico, Haiti, Brazil, southern Europe, Malaysia, and Pakistan.

The genus includes a few modern species that are commercially-fished such as the blue swimming crab.