The American Oyster, Crassostrea virginica (Gmelin, 1791) is an important species in bays, estuaries and coastal waters in Texas.

One easy way to identify this species is the dark purple muscle scar in the interior of the valve, in the shape of a comma.

The specimen shown here was found at Copano Bay, Texas. It was featured in a poster on Texas estuarine mollusks I made with Paul Montagna:
https://www.researchgate.net/profile/Fabio_Moretzsohn/publication/253327815_Estuarine_molluscs_of_Texas/links/0046351f7f5eaba72c000000?ev=pub_int_doc_dl&origin=publication_list&inViewer=true

Oyster reefs provide home and shelter for a number of coastal and estuarine species, including fishes and invertebrates. Oyster reef restoration is an important activity that will likely be part of many of the restoration projects starting soon in response to the Deepwater Horizon Oil Spill (2010).

Read more about this species in Tunnell et al (2010)’s Encyclopedia of Texas Seashells, page 321, and in the Texas Seashells, A Field Guide (Tunnell, Barrera and Moretzsohn, 2014), on page 169.