†family Triadocidaridae Smith 1994 (sea urchin)
Echinoidea - Euechinoidea - Triadocidaridae
Full reference: A. B. Smith. 1994. Triassic echinoids from Peru. Palaeontographica Abteilung A 233:177-202
Parent taxon: Euechinoidea according to A. B. Smith 1994
Sister taxa: Acroechinoidea, Diadematacea, Echinacea, Echinothurioida, Galeroclypeus, Loriolella, Serpianotiaroida, Triadotiaroida
Subtaxa: Levicidaris Megaporocidaris Mikrocidaris Parvicidaris Triadocidaris Vinchuscanchaia Zardinechinus
Type: Triadocidaris
Ecology: epifaunal grazer-deposit feeder
Distribution:
• Triassic of Canada (1: British Columbia collection), China (4), East Timor (1), Hungary (3), Italy (6), Peru (6), Poland (1), Slovenia (1), United States (1: Idaho)
Total: 24 collections including 57 occurrences