Cretaceous Fossil Sea Urchin Psephechinus
A living sea urchin
Echinoid (Sea Urchin) Fossil Psephechinus Phylum Echinodermata; Class Echinoidea; Superorder Echinacea; Order Salenioida, Family Stomechinidae, Genus Psephechinus sp. Jurassic (Cenomanian Stage) Gouramna, Morocco
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