Asterocidaris

Asterocidaris is a genus of fossils sea urchins in the family Hemicidaridae. These epifaunal grazer-deposit feeders lived in the Middle and Upper Jurassic age (from 171.6 to 161.2 Ma).
Description.
These fossil spined echinoid sea urchins can reach a diameter of about , with spicules of about 69x60mm. They are hemispherical, flattened beneath, with small apical disc.
Distribution.
Fossils of species within this genus have been found in the Middle to Upper Jurassic sediments (Bajocian-Oxfordian) in Europe, Madagascar and Africa (Morocco).