|height 34.5 mm|
a fossil specimen
|height 29 mm|
a modern specimen
Turritella cooperi Carpenter, 1864
AGE RANGE: Cenozoic (early Pliocene to Holocene = about 5 million years ago to today)
GEOGRAPHIC RANGE: Central California to Cedros Island off the west coast of central Baja California, Mexico.
REMARKS: Turritella cooperi is characterized by two having two principal spiral ribs on its whorls, but there are variations. This species is very common in storm-related deposits of late upper Pliocene age in southern California. Modern specimens are rarely found as beach drift on some central and southern California beaches. The ocean temperature north of central California is simply too cold today for Turritella. Most modern species of Turritella are found in tropical waters.