Palaeocyclus porpita SOLD

Palaeocyclus porpita it's a rough coral extinct in the Silurian period, frequently called coral button due to its small circular discoidal shape.

Rugged corals (rough either Tetracoralla) are an extinct group of anthozoans (a class of animals from the phylum Cnidaria that are exclusively polyp-shaped) tetracoralaria (when radiating septa are present, they are generally in multiples of four. The presence of these septa causes these corals to present bilateral symmetry, unlike the common cnidarians).

The Ireviken event was the first of three relatively minor extinction events (Ireviken, Mulde and Lau) during the Silurian period. The event is best recorded in Ireviken, Gotland, where more than 50% of trilobite species became extinct.