Image: Tullimonstrum gregarium

Description: The enigmatic Carboniferous animal, Tullimonstrum gregarium known only from Mazon Creek, swimming through seaweed. Below it is a string of aitches, Etacystis communis. Next to T. gregarium are a pair of crustaceans Cyclus americanus.
Title: Tullimonstrum gregarium (obsolete reconstruction)
Credit: Own work
Author: Stanton F. Fink
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