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Catalog Number 2014.009.047
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. This Cardium specimen is attached to two other smaller specimens. The Cardium (a large, scalloped-shaped shell) sits at the bottom. Ribs on shell appear to extend the entire length of shell. Attached at the top are two smaller shells, flat and oval in shape. These smaller shells are likely Macoma sp. A third type of shell resembling a snail is attached just above the Cardium shell. The top portion of the fossil appears red, likely from iron oxide present. Underside surface contains shell fragments and a partial imprint of a large, ribbed shell.
Object Name Shell, Animal
Collection 3D - Paleontology
Title Cardium nuttalli, 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 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-3.75 W-4 D-4.75 inches
Search Terms Fossils
South San Francisco
Merced Formation
Subjects Fossils
Marine biology