what species of clam is this?

[secretvillain]

I found this in Jefferson county, Indiana while walking on the hillside about 200 ft up. There are many creeks and brooks with limestone beds in the valleys around the area that are full of fossil clams like this. The fossils on the hillside are less eroded since they are not in water-filled creeks. Most of the fossils found on the hills are in big limestone plates, and are all smashed together and on top of one another, but sometimes I'll find some individual clams like this one and some coral too. This clam is 2.7 cm wide, 2.1 cm tall, and 1.7 cm thick but I usually find smaller ones and occasionally some larger ones, but this is one of the best preserved ones. They have a very distinct M or W shape on the front. Does anyone know what species this is and if its still around today?

[Fossildude19]

Welcome to the Forum.  

I believe that is an Ordovician period aged Platystrophia brachiopod, rather than a clam.   

They went extinct sometime in the Silurian period.

The differences between brachiopods and clams:   

 

 

  Image from: LINK                                                                                                                  Image from :  LINK

 

                   

 

 

[secretvillain]

Thank you! I'm glad I know the difference between a brachiopod and a clam now 

[Tidgy's Dad]

Platystrophia is now known as Vinlandostrophia in North America. 

 

[Shamalama]

12 hours ago, Tidgy's Dad said:

Platystrophia is now known as Vinlandostrophia in North America. 

 

Correct. Check this link out to see if you can ID down to the species: http://www.ordovicianatlas.org/atlas/brachiopoda/rhynchonellata/orthida/platystrophiidae/vinlandostrophia/

 

I am thinking it's Vinlandostrophia acutilirata