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Object Record

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Catalog Number 2014.009.010
Description Clinocardium nuttalli, 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 shells, separated by a layer of sediment. Top shell has ridges that appear to run the length of its surface. One large fracture runs across the width of the shell, with another fracture that runs the length, from ligament to front edge. Shell is fragmented along its front edge. Bottom shell has larger ridges, indicating that these two shells are likely not from the same animal. Most of the bottom shell is lost, but ridges appear to have extended the length of the shell. Both shells are white and sediment between the two is light brown.
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-0.875 D-1 inches
Search Terms Fossils
Shellfish
Merced Formation
South San Francisco
Subjects Fossils
Shells
Shellfish
Marine biology