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Object Record

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Catalog Number 2014.009.011
Description Clinocardium nuttali, basket cockle fossil dating from between 1.5 million years ago to .75 million years ago commonly found at low tide in littoral (sandy and muddy bottom) or sub-littoral (open bay, muddy marine) zones. Fossil specimen is comprised of two different shells. Top shell is white, more rounded in shape, with ridges that extend along the length of the shell. Multiple cracks run throughout the surface, with loss of shell along front edge and along one side. Bottom shell is also white, but is flatter and more oval in shape. Bluish growth rings are visible on the shell surface. Shell loss along the front edge of shell, and a fracture towards the back of the shell, exposing underlying grayish brown sediment. Cracks run throughout surface of bottom shell.
Object Name Shell, Animal
Collection 3D - Paleontology
Title Clinocardium nuttalli, Basket Cockle Fossil, 1.5-.75 Ma
Date 1.5 - .75 Ma
Kingdom Animalia (Animals)
Phylum Mollusca (Molluscs)
Class Bivalvia (Bivalves)
Order Veneroida (bivalve order)
Family Cardiidae (Cockles)
Genus Clinocardium
Species nuttalli
Inscription Text none
Provenance Fossils taken from Merced Formation collected at Westborough Boulevard at Highway 280 in the late 1970s or early 1980s. (See Yancey 1978, Fig. 2: Artifacts taken from E Stratified Section/D-5929). Most specimens (especially clams) in this collection are not extinct and can still be found in the Bay Area.
Notes Retired Geologist Ken Lajoie identified on 4/24/2014.
Clinocardium nuttali (Common name: Basket Cockle) still thrives in the Bay Area.
Dimensions H-0.625 W-0.75 D-1.125 inches
Search Terms Fossils
Shellfish
Merced Formation
South San Francisco
Subjects Fossils
Shells
Shellfish
Marine biology