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Object Record

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Catalog Number 2014.009.017
Description Cardium sp.,cockle (clam) fossil, 1.5-.75 Ma 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 has a fully preserved top and bottom shell, still connected by the ligament. Both shells are concave in shape. A fracture runs down the middle of the top shell. Area closest to the ligament is white; the remaining area is multicolored in varying shades of brown, beige and reddish brown (likely indicating the presence of iron oxide). Growth lines are easily visible. The bottom shell has a fracture that runs diagonally across the shell. Shell is multi-colored in shades of white, beige and reddish brown. Growth lines are easily visible.
Object Name Shell, Animal
Collection 3D - Paleontology
Title Cardium sp.,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 sp.
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.
Cardium sp. (Common Name: Cockle Shell) still thrives in the Bay Area.
Dimensions H-1.375 W-2 D-1.875 inches
Search Terms Fossils
Merced Formation
South San Francisco
Subjects Fossils
Marine biology