Paraceraurus exsul

Paraceraurus exsul is a species of trilobite that lived in St. Petersburg Region and Tver Region (in erratic blocks) of Russia, Estonia, Finland (Åland, in erratic blocks), Sweden, North Germany (in erratic blocks), Lithuania and Belarus during the Upper Llanvirnian Stage (463.5-460.9 Ma) of the Middle Ordovician. These trilobites can reach a length of about 16 cm. They show a square front edge, large genal spines on the cheeks and characteristic long pygidial spines. Genal spines are curved usually inward and upward.