Fardenia subplana Brachiopod

Two specimens shown both appear to be the inside of the shell.  Both are Waldron Shale fossils that appear to be Fardenia subplana.  This brachiopod was named by Conrad in 1842 who called it Streptorhynchus subplanus.  A similar fossil is found in the Rochester Shale of New York but called Coolina subplana.

This is the 14 Waldron Shale brachiopod species I have identified in my collection see the listing at this post.

Strombus "Fighting Conch" Fossil

Strombus alatus? (Gremlin, 1791) also known as a "fighting conch" found in Hendry County, Florida.  Fossil is thought to be from the Eocene.

A nice blog about these creatures with related website/Twitter feed is the Fossil Murex by Greta Polites.  The thread about the Strombus on Fossil Forum with some nice research by the user MikeR makes for good reading.

Thanks to Herb for the fossil.  Pictures are all of the same specimen.

Astraeospongium meniscus

Astraeospongium meniscus sponge (Porifera) fossil found in the Brownsport Formation of Hardin County, Tennessee.  This Silurian period fossil as the distinction of being included on the 2011 Science Olympiad fossil list.  This Astraeospongium (class Calcarea) existed in the Silurian through Devonian periods.

See this nice write up on the web page of the The Virtual Petrified Wood Museum.

Thanks to Herb for the fossil and new insight on Silurian sponges.  Next picture shows under side of the fossil.

As of this writing two of these sponges were for sale on eBay in an estate collection auction.  The fossils are from Decatur County, Tennessee and the auction ends March 20, 2011.