Progeronia

Progeronia is a genus of ammonites belonging to the family Perisphinctidae.
These fast-moving nektonic carnivores lived in the Jurassic period, from 155.7 to 150.8 Ma.
Species.
Species within this genus include:
Description.
Shells of "Progeronia" species can reach a diameter of . These large shell are large and involute, with a bifurcated or trifurcated ribs.
Distribution.
Fossils of species within this genus have been found in the Jurassic sediments of Algeria and Hungary.