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Peronidella

Peronidella is an extinct genus of Calcareous sponges found in marine sedimentary rocks dated between the Devonian and the Cretaceous periods.

These sponges had cylindrically shaped walls, with a typical diameter of 2 cm, with a small platform at the top, showing the position of the Osculum. Many species, such as Peronidella furcata, were colonial; however, several solitary species are known.

These sponges are relatively abundant in European chalks