anyone know what clam this is

[2020 Worst Year]

 

[hart24601]

Appears to be a typical derasa.

 

[Miami Reef]

Agreed.

 

[minus9]

T. derasa as mentioned by others.

 

[jamesfatherree]

Lots of derasas: https://www.flickr.com/photos/jameswfatherree/albums/72177720308825119

 

[minus9]

Lots of derasas: https://www.flickr.com/photos/jameswfatherree/albums/72177720308825119

Btw, I love the new book. Lots of great info and pics.