Hyolithid Fossils
Phylum Hyolitha
Geological Time: Lower Cambrian
Size (25.4 mm = 1 inch): Hyolithids are 23 and 21 mm; matrix ~ 65 x 55 mm
Fossil Site: Pioche Shale, Nevada
Fossil Code: INV15
Price: Sold
The
Hyolithids are an extinct group of problematic animals that appeared in
the Cambrian and persisted into the Permian. They had a long, conically-shaped,
closed shell, with a lid (operculum) covering the opening, and a pair of
long, horn-like outgrowths. The animal lived on the sea-bottom, or partly
buried. They are 
sometimes
classified as a Mollusk, though as a distinct separate class. They reached
their peak in the Cambrian and declined thereafter.
This plate has two larger Hyolithids. They come from the famous, Lower Cambrian, Pioche Shale in Nevada where they are sometimes found in association with Olenellid trilobtes. The long skinny trace to the right of the Hyolithids is a Priapulid worm gut trace.
Add a new Class of fossil animal not often offered to your fossil collection.
