Lytocrioceras
 Lytocrioceras is an ancyloceratine ammonite from the Lower Cretaceous with a shell that resembles a safety pin. The shell begins as a loosely wound spiral followed by a straight shaft which makes a U-turn to go back is somewhat the opposite direction ending in a jog offset from the original coil. Lytocrioceras was originally included in the Ancyloceratidae (Lytoceratina) united with other similar forms but has since been reassigned to the Macroscaphitidae.