Order Hexactinosa Schrammen 1903
Alternative spelling: Hexactinosida
Parent taxon: Hexasterophora according to R.E.H. Reid 2004
See also Bambach et al. 2007, Finks and Rigby 2004, Rigby and Albi 1996, Rigby and Mohanti 1993, Senowbari-Daryan and Rigby 2015 and Sepkoski 2002
Sister taxon: Lychniscosida
Subtaxa: Aphrocallistidae Aulocalycidae Auloplacidae Caesaria Carinthiaspongus Caseispongia Clavularia Cribrospongiidae Cystispongiidae Emplocidae Euretidae Euryplegmatidae Farreidae Furcicanalis Idiodictyon Imbricareola Laocaetis Misonia Multiloqua Mysterium Octobrum Pileolitoidea Pillaraspongioidea Polysyge Porospongia Rhogostomium Rhombedonium Scopularia Scotospongia Staurodermatidae Tesselispongia Tremaphorus Tretodictyidae Vermifistula Xenoschrammenus