Hemicidaridae is a family of extinct sea urchins characterized by large, massive, club-shaped spines.
These epifaunal grazer-deposit feeders lived in Jurassic and Cretaceous ages (from 189.6 to 112.6 Ma).
Taxonomy List of genera and subfamilies: Subfamily Hemicidarinae Wright, 1857 † Asterocidaris Cotteau, 1859 † Gymnocidaris L. Agassiz, 1838 † Hemicidaris L. Agassiz, 1838 † Subfamily Pseudocidarinae Smith & Wright, 1993 † Cidaropsis Cotteau, 1863 † Pseudocidaris Pomel, 1883 † Gymnocidaris L. Agassiz, 1838 †
Distribution Fossils of species within this genus have been found in the Jurassic and Cretaceous sediments in Europe, Africa, North America and China.
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