Nerineoids, so typical of the Jurassic and Early Cretaceous in Europe, are usually rare and lacking in diversity in North America north of Mexico. This is especially true of the Pacific slope faunas. Only three species of nerineoid gastropods have previously been reported from the Cretaceous of California (Saul and Squires, 1998). The oldest of these species, Aphanoptyxis andersoni Saul and Squires, 1998, is from the Early Cretaceous (Hauterivian) in northern California. The other two species are Late Cretaceous (Turonian): Aphanoptyxis californica Saul and Squires, 1998, is from northern California, and Nerinella santana Saul and Squires, 1998, is from a locality and strata in southern California near the occurrence of Nerinella califae n. sp. The description of N. califae n. sp. gives California the greatest diversity of Turonian northeastern Pacific slope nerineoids, namely, Aphanoptyxis californica and two species of Nerinella. These Turonian nerineoids are also, thus far, the geologically youngest North American Pacific slope nerineoids.
Aeromagnetic and aeromagnetic-based geologic maps of the Coastal Belt, Franciscan Complex, northern California
