Monopfyllites sphaerophyllus Hauer

This representative of the cephalopods from the subclass Amonoidea, found in lime near Han-Bulog, lived about 245 million years ago (Middle Triassic, Anisian) in the deep sea which covered this area at the time. Amonoidea shells resemble the nautilus, a species which now inhabits the Indian Ocean, and they are most closely related to cuttlefish, octopuses, and squid. Amonoidea went extinct towards the end of the Cretaceous Period, 65 million years ago.