FOSSILS SPECIMEN: BIVALVIA

Fossils are defined as any evidence of prehistoric life. There are two types of fossils: Body Fossils include remains of skeletal bones, shell, carapace, test and teeth. Trace Fossils are clues the organism existed such as footprints, tracks, burrows and coprolites (fossil dung).

The class: Bivalvia meaning “two valves or shells” are classified under the Kingdom: Animalia and Phylum: Mollusca. The group includes modern and fossil members of the groups commonly called pectin, lima, oysters, mussels, and clams. The earliest members of this class first appear in the fossil record during the Lower Cambrian and can be found all over the world today in the Holocene.

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autibranchia – Infraclass: Pteriomorphia – Order: Pectinida – Superfamily: Pectinoidea – Family: Pectinidae

(pectin)

Middle Ordovician to Holocene

Bivalve Pecten

Lower Cretaceous

Fort Worth, Tarrant County, Texas

Bivalve Pecten

Cretaceous (100 mya)

Gratson Marl Formation, Rayzor Ranch, Denton, Texas

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autobrachia – Infraclass” Pteriomorphia – Order: Limida – Superfamily: Limoidea – Family: Limidae

(lima)

Jurassic to Holocene

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Order: Ostreida – Family: Gryphaeidae

(prehistoric oysters)

Early Triassic to Holocene

Bivalve Texigryphaea

Lower Cretaceous

Texas

Bivalve Gryphaea “Devil’s Toenail”

Lower Cretaceous

Fort Worth, Tarrant County, Texas

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autobrachia – Infraclass: Pteriomorphia – Order: Ostreidae

(true oysters)

Middle Jurassic to Holocene

Bivalve Rastellum sp.

(Dorsal View)

Cretaceous

Texas, United States

Bivalve Fossil Oyster

Cenozoic

North America

Bivalve

Gyrostrea

Cretaceous

Texas, United States

Bivalve Oysters 

Lopha bellaplicata bellaplicata

Post Oak Creek south of Sherman Texas United States

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Probranchia – Order: Nuculoida

(saltwater clams)

Middle Carboniferous to Holocene

Bivalve Paleyoldia

Pennsylvanian

Jacksboro, Jack County, Texas

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autobranchia – Infraclass: Heteroconchia – Order: Cardiida

(marine bivalve clams)

Middle Carboniferous to Holocene

Bivalve Protocardia texana

Cretaceous

Texas

Bivalve Protocardia (internal cast)

Lower Cretaceous

Kerrville, Texas

Bivalve Pteropsella lapidosa

Eocene

Stone City Formation, Bryan, Texas

Bivalve Arcinella arcinella

(spiney jewel box)

Calusa Mine Pit, Ruskin, Florida

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autobranchia – Infraclass: Pteriomorphia – Order: Myalinida

(mussels)

Middle Carboniferous to Holocene

Bivalve

Cretacous

North America

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autobranchia – Infraclass: Heteroconchia – Order: Hippuritida

(rudist clams)

Cretaceous

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autobranchia – Infraclass: Heteroconchia – Order: Trigoniida

(ridged clams)

Cretaceous

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Superorder: Imparidentia – Order: Adapedonta – Family: Hiatellidae

(wrinkled rock-borer, arctic hiatella, and arctic saxicave)

Cretaceous to Holocene

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autobranchia – Infraclass: Pteriomorphia – Order: Arcida

(arks)

Cretaceous to Holocene

Bivalve Arcalinga pensylvanica

Cenozoic

Florida, United States

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Pterygota – Infraclass: Neoptera – Order: Hemiptera

(jinggle shells)

Cretaceous to Holocene

Bivalve Anomia argentaria (Morton)

Cenozoic

Hollywood Road. Clack County, Arkansas

Found in mud bank in road ditch

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autobranchia – Infraclass: Heteroconchia – Order: Solenida

(saltwater clams)

Lower Cretaceous to Holocene

Kingdom: Animalia – Phylum: Mollusca – Class: Bivalvia “two valves or shells” – Subclass: Autobrachia – Infraclass: Heteroconchia – Order: Pholadida

(smooth clams)

Cretaceous

Bivalve Notocorbula texana

Eocene

Stone City Formation, Bryan, Texas