Wikipedia
Californites
Californites is a genus of the Upper Triassic clydonicacean family Clionitidae with a discoidal, evolute shell and radial tuberculate ribs that end in strong ventrolateral spines. The whorl section is described as trapezoidal. The venter is low-arched, smooth, and has a strong but narrow median groove.
Californites comes from the Carnian of California.