It’s no ordinary oyster, of course, because it comes from Texas. It certainly is the largest oyster I’ve ever seen. Wooster received it as part of a large donation in 2010. (You can see students studying it in this previous blog entry.)
All we know is that it came from Texas (a notoriously big place) and the Eocene Series. It appears to be the extinct oyster Crassostrea gigantissima (Finch, 1824). Curiously, this is the first fossil species described from the Paleogene of North America (see Howe, 1937). It is worth quoting the entire description:
Fossils. This extensive formation is chiefly composed of a large species of ostrea, which I believe has not yet been described. A specimen of it may be seen in the Philadelphia museum; it is twelve inches long and two and three-quarters wide, and each valve from half to two and a quarter inches thick — Major Ware says they occur larger; on account of their great size I propose to call them Ostrea Gigantissima. The shells appear but slightly changed by their residence in the earth, and are in many parts used for burning into lime. (Finch, 1824, p. 40)
This is what it took to name a new species in 1824! Since then, of course, we have a detailed set of rules for naming animal taxa detailed in the International Code of Zoological Nomenclature. The Lawrence (1991) reference below is an example of what we often have to do in order to bring old names like “Ostrea Gigantissima” up to, well, Code.
The interior of the attaching valve of Crassostrea gigantissima.
The top surface of our giant oyster is riddled with these small holes. They are produced by the boring sponge Entobia, which is the next Fossil of the Week.
References:
Finch, J. 1824. Geological essay on the Tertiary Formations in America. The American Journal of Science and Arts 7: 31-42.
Howe, H.V. 1937. Large oysters from the Gulf Coast Tertiary. Journal of Paleontology 11: 355-366.
Lawrence, D.R. 1991. The neotype of Crassostrea gigantissima (Finch, 1824). Journal of Paleontology 65: 342-343.
How much are Giant oyster fossils worth?
Sorry. We don’t do valuations.
I found a Large Cretaceous Oyster on the Brazos river.
If you like I can send you a photo?
My family and I enjoy rock hounding.
It’s a pretty neat find.
Sure, Charlie, you can send me an image of that oyster. Be sure to have a scale in it. You can email it to my college address.
would you mind if we used the picture in our newsletter Paleo Society of Austin?, I was in that area before Christmas but did not find the bed. Its around Roma Texas on the Rio Grande. I am going back latte but may not be able to collect. they have these in Georgia also
Melvin noble Feild trip chair Paleo society of Austin (Texas)
Sure, Melvin, you may use any images of mine you find online, including these.