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).
[2] [4] These fossil spined echinoid sea urchins can reach a diameter of about 25 millimetres (0.98 in), with spicules of about 69x60mm.
[5] They are hemispherical, flattened beneath, with small apical disc.
[6] Fossils of species within this genus have been found in the Middle to Upper Jurassic sediments (Bajocian-Oxfordian) in Europe, Madagascar and Africa (Morocco).