Phylum: Mollusca (Mollusks)

Class: Bivalvia - Bivalves - Pelecypods 
Subclass Pteriomorphia 
Family: Inoceramidae

Cretaceous Period:  (click for Pennsylvanian Period)
Inoceramus sp. clam (impression) Strata: Austin Chalk Period: Cretaceous  Loc: Collin County, TX.  Aug. 2, 2014.	Inoceramus sp. clam Strata: Austin Chalk Period: Cretaceous  Loc: Collin County, TX.  2023.	Inoceramus sp. clam Strata: Austin Chalk Period: Cretaceous  Loc: Collin County, TX.  2023.

Phylum: Mollusca (Mollusks)

Class: Bivalvia - Bivalves - Pelecypods 
Subclass Heterodonta 
(clams, rudists)

Order: Trigoniodia  Family: Tigoniidae Trigonia sp. Strata: Weno (upper) Period: Cretaceous (98 mya) Loc: Tarrant County, TX.  June 13, 2009. (by Donna B)	Order: Trigoniodia  Family: Tigoniidae Trigonia sp. Strata: Weno (upper) Period: Cretaceous (98 mya) Loc: Denton? County, TX.  28 March 2021.
Order: Anomalodesmata   Family: Pholadomyidae Pachymya sp. "shoe clam" Strata: Mainstreet Period: Cretaceous (97 mya) Loc: Tarrant County, TX.  2006.	Order: Pholadomyida Family: Pholadomyidae Homomya sp. (internal mold) Strata:  Grayson Period: Cretaceous (95-97 mya) Loc: Denton County, TX.  Mar. 14, 2009.
Pholadomya sp.?   Strata:  Goodland Period: Cretaceous (103-105 mya) Loc: Tarrant County, TX.  July 13, 2008.	Order: Veneroida   Family: Cardiidae Protocardia texana Strata:  Goodland Period: Cretaceous (103-105 mya) Loc: Tarrant County, TX.  2005.
Arca sp. ? Strata:  Walnut Period: Cretaceous (105 mya) Loc: Parker Co., TX.  Feb. 1, 2009.	Arca sp. ? Strata: Grayson Period: Cretaceous (95-97 mya) Loc: Tarrant Co., TX.
Order: Limoida  Family: Limidae Lima wacoensis Strata:  Goodland Period: Cretaceous (103-105 mya) Loc: Tarrant County, TX.  Jan. 18, 2009.
Cyprimeria gigantica Strata: Grayson Period: Cretaceous (95-97 mya) Loc: Tarrant Co., Tx. 6 March 2011	Nucula wenoensis Strata:  Weno Period: Cretaceous (98 mya) Loc: Tarrant Co., TX.  April 2, 2011.
"sp." = species not known or unsure

Class: Bivalvia - Bivalves - Pelecypods 
Subclass: Heterodonta (clams, rudists)
Family: Pinnadae (Pinna clams)

Pinna sp. Strata: Grayson Period: Cretaceous (103-105 mya) Loc: Denton County, TX.   Sept. 2, 2007.

Pinna comancheana Strata: Goodland Period: Cretaceous (103-105 mya) Loc: Tarrant co., Tx.