Pyritized Brachiopods (Paraspirifer bownockeri)

Middle Devonian. Silica Shale, Lucas County, Ohio, USA. Brachiopods ruled the sea bottom for 300 million years. Today they are ecological fugitives; unless you night dive in the tropics, you will probably never see one alive. Brachiopods are rare and secretive, and they are outnumbered by clams 1,000 to one.