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Object Record

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Catalog Number 2014.009.045
Description Cardium nuttalli, 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. Top and bottom valves of this specimen remain connected by an intact ligament. Reddish sediment and shell fragments fill most of the spaces between ribs of the top valve. Space between four ribs are free of sediment. Most of the bottom valve has been lost (except the portion that is adjacent to the ligament), revealing the sediment between the valves. A cross section of the specimen reveals the thickness of each valve.
Object Name Shell, Animal
Collection 3D - Paleontology
Title Cardium nuttalli, Cockle Clam 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 Cardium
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 4/8/2014.
Cardium nuttali (Common name: Cockle Shell) are large shells, measuring up to 14 centimeters in length. This species still thrives in the Bay Area.
Dimensions H-2.5 W-4.75 D-4.75 inches
Search Terms Fossils
Merced Formation
South San Francisco
Subjects Fossils
Marine biology