This species has a medium-size shell (4 to 5 inches in length) with an overall fusiform shape. Its six convex whorls have 16 to 18 axial ribs nodulated by the crossing of weaker spiral ribs. There is a single parietal tooth near the top of the aperture.
Abapertural view of same modern specimen.
The fossil record of F. oregonensis is from approximately middle Pliocene (approximately four million years ago) to recent.
The two pictures shown below are of a fossil specimen 55.5 mm height (2.2 inches) of late Pleistocene age (30,000 to 50,000 years old) from a marine terrace at a beach cliff near Santa Barbara. The shells in this marine-terrace deposit lived during the Wisconsin Glacial Stage, which was the fourth and last stage of the great Pleistocene Ice Age. Based on a comparison with modern bathymetric, temperature, and geographic ranges, the shells indicate a maximum water depth of 10 m and a temperature range from 11 to 20 degrees Celsius (cool temperate). This would have been cooler than the sea temperature off Santa Barbara today but similar to that off the northern California coast today.
|Apertural view of a fossil specimen missing its upper part.|
Abapertural view of fossil specimen.