†family Archaeocidaridae M'Coy 1844 (sea urchin)
Full reference: F. M'Coy. 1844. A synposis of the characters of the Carboniferous limestone fossils of Ireland 1-274
Parent taxon: Echinoidea according to A. Kroh and A. B. Smith 2010
Sister taxa: Acrosalenioida, Bromidechinus, Cassiduloidea, Cidarites, Cidaroidea, Diplocidaroida, Disasteroida, Dysaster, Echinocrinus, Echinoida, Euechinoidea, Gnathostomata, Hemicidaroidea, Oligopygoida, Parechinus, Perischoechinoidea, Radiolus, Regularia, Temnopleuroida
Subtaxa: Archaeocidaris, Eocidaris, Lepidocidaris, Nortonechinus, Polytaxicidaris, Silurocidaris, Xenocidaris
Type: Archaeocidaris
Ecology: epifaunal grazer-deposit feeder