Opinions from H. B. Fell 1966
- 'Alpicidaris belongs to Cidarinae'
- 'Anaulocidaris belongs to Miocidaridae'
- 'Anisocidaris belongs to Psychocidaridae'
- 'Aplocidaris belongs to Miocidaridae'
- 'Archaeocidaridae belongs to Cidaroida'
- 'Archaeocidaris belongs to Archaeocidaridae'
- 'Austrocidaris belongs to Ctenocidarinae'
- 'Balanocidaris belongs to Cidarinae'
- 'Caenocidaris belongs to Psychocidaridae'
- 'Calocidaris belongs to Cidarinae'
- 'Chondrocidaris belongs to Rhabdocidarinae'
- 'Cidaridae is corrected as Cidaroida and belongs to Perischoechinoidea'
- 'Cidaridae belongs to Cidaroida'
- 'Cidarina was reranked as the unranked clade Cidarinae and belongs to Cidaridae'
- 'Cidaris belongs to Cidarinae'
- 'Cidarites is a subjective synonym of Cidaris'
- 'Cidarites pistillaris is recombined as Prionocidaris pistillaris'
- 'Ctenocidarina was reranked as the subfamily Ctenocidarinae and belongs to Cidaridae'
- 'Cyathocidaris belongs to Cidarinae'
- 'Dicyclocidaris belongs to Miocidaridae'
- 'Diplocidaridae belongs to Cidaroida'
- 'Diplocidaris belongs to Diplocidaridae'
- 'Echinocrinus is an objective synonym of Archaeocidaris'
- 'Eucidaris belongs to Cidarinae'
- 'Goniocidarina was reranked as the subfamily Goniocidarinae and belongs to Cidaridae'
- 'Goniocidaris belongs to Goniocidarinae'
- 'Histocidarina was reranked as the subfamily Histocidarinae and belongs to Cidaridae'
- 'Histocidaris belongs to Histocidarinae'
- 'Lanternarius belongs to Perischoechinoidea'
- 'Lepidocidaris belongs to Archaeocidaridae'
- 'Megacidaris belongs to Rhabdocidarinae'
- 'Merocidaris belongs to Psychocidaridae'
- 'Mikrocidaris belongs to Miocidaridae'
- 'Miocidaridae belongs to Cidaroida'
- 'Miocidaris belongs to Miocidaridae'
- 'Nortonechinus belongs to Archaeocidaridae'
- 'Notocidaris belongs to Ctenocidarinae'
- 'Pachycidaris belongs to Miocidaridae'
- 'Paracidaris belongs to Cidarinae'
- 'Parhabdocidaris belongs to Rhabdocidarinae'
- 'Phyllacanthus belongs to Rhabdocidarinae'
- 'Plegiocidaris belongs to Cidarinae'
- 'Plococidaris belongs to Rhabdocidarinae'
- 'Polycidaris belongs to Histocidarinae'
- 'Polytaxicidaris belongs to Archaeocidaridae'
- 'Poriocidaris belongs to Histocidarinae'
- 'Porocidaris belongs to Rhabdocidarinae'
- 'Prionocidaris belongs to Rhabdocidarinae'
- 'Procidaris belongs to Histocidarinae'
- 'Psychocidaridae belongs to Cidaroida'
- 'Rhabdocidarinae was reranked as a subfamily and belongs to Cidaridae'
- 'Rhabdocidaris belongs to Rhabdocidarinae'
- 'Sardocidaris belongs to Psychocidaridae'
- 'Silurocidaris belongs to Archaeocidaridae'
- 'Sinaecidaris belongs to Stereocidarinae'
- 'Stereocidaridae was reranked as the subfamily Stereocidarinae and belongs to Cidaridae'
- 'Stereocidaris belongs to Stereocidaridae'
- 'Stylocidaris belongs to Cidarinae'
- 'Temnocidaris belongs to Stereocidarinae'
- 'Tetracidaris belongs to Diplocidaridae'
- 'Tretocidaris belongs to Cidarinae'
- 'Triadocidaris belongs to Miocidaridae'
- 'Tylocidaris belongs to Psychocidaridae'
- 'Xenocidaris belongs to Archaeocidaridae'