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The mission of the San Mateo County Historical Association is to inspire wonder and discovery
of the cultural and natural history of San Mateo County.

Object Record

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Catalog Number 2014.009.004
Description Achatinoidea sp., sea snail 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 is pale brown in color and embedded in darker brown sediment. Sediment is also exposed where shell loss has occurred. On bottom portion of fossil (sediment), there are areas that have reddish streaks, likely indicating the presence of iron oxide. Underside surface contains exposed snail fossil and other shell fragments.
Object Name Shell, Animal
Collection 3D - Paleontology
Title Achatinoidea sp., Sea Snail Fossil, 1.5-.75 Ma
Date 1.5 - .75 Ma
Kingdom Animalia (Animals)
Phylum Mollusca (Molluscs)
Class Gastropoda (Snails, limpets)
Order Achatinoidea (Snails)
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 tried to identify on 4/24/2014 but could not identify Genus and species.
Dimensions H-1 W-1.875 D-1.375 inches
Search Terms Fossils
Merced Formation
South San Francisco
Subjects Fossils
Marine biology