Bivalvia
Modern Day Bivalves
Familiar bivalves today include clams, oysters, mussels and scallops. There are 10,000+ described living species.
In the Museum Collections
View specimen list here.
Total bivalve specimens: 3748
Total identified species: 300+
Specimens from Arkansas: 2451
Identified species from Arkansas: 33
Fossil Record
Bivalve fossils first appear in the Cambrian Period (542 to 488 million years ago).
Oyster shells (UA Museum), Ostrea congesta, Marlbrook Formation (Millwood Reservoir, AR), Upper Cretaceous (100.5 – 66 million YA). Map indicates county where specimens were found.
Pelecypods (Inoceramus sp.) specimens (UA Museum), Nacatoch Formation (Clark County, AR), Upper Cretaceous (100.5 – 66 million YA). Map indicates county where specimens were found.
Bivalve (UA Museum), Exogyra ponderosa, Marlbrook Formation (Millwood Reservoir, AR), Upper Cretaceous Age (100.5 – 66 million YA). Map indicates county where specimens were found.
Bivalves (UA Museum), Inoceramus comancheanus, Annona Formation (Millwood Reservoir, AR), Upper Cretaceous (100.5 – 66 million YA). Map indicates county where specimens were found.
Image Credits:
- Heyde, Manfred. Seashells: marine bivalves and gastropods from Shell Island, a coastal peninsula south of Harlech Castle, in North Wales/ Great Britain. There we found about 25 different species out of 200 shells we picked up. Wikimedia Commons. CC BY 3.0.
- Oberg, Danielle. Arkansas map.
- Oberg, Danielle. U of A Museum paleontological specimens.
