Invalid subtaxa: Cyclindrocyathus Alloiteau 1952 [invalid subgroup], Eusmiliopsis [invalid subgroup], Saltastraea [invalid subgroup], Thamnasteria cycloides Eguchi 1951 [invalid subgroup], Thamnasteria komagataensis Eguchi 1951 [invalid subgroup], Thamnasteria maxima Eguchi 1951 [invalid subgroup], Thamnasteria protoserioides Eguchi 1951 [invalid subgroup], Thamnasteria rikuzenica Eguchi 1951 [invalid subgroup], Thecoseriopsis [invalid subgroup]
Parent taxon: Zoantharia according to Y. Ezaki 2000
Sister taxa: Kilbuchophyllida, Pentasmiliida, Tabulaconida
Subtaxa: Acropsammia, Adekoheastrea, Agathiphylliidae, Amphiastraeina, Anisastraea, Annotocyathus, Anomopora, Apelismilia, Archaeocoeniina, Archaeofungiina, Archaeolasmogyra, Astraeoina, Astrocoeniina, Aulastraeoporidae, Bavarosmilia, Budiopsis, Calameastolia, Carantophyllum, Carcicocaenia, Caryophylliina, Chevalierismilia, Chorisastraea, Clausastraeopsis, Clonosmilia, Coelomeandra, Cyclastraeidae, Cyclismilia, Cylindrosmilia, Cynaria, Decaheliocoenia, Dendrophylliina, Dermosastraea, Desmocoenia, Dichotomosmilia, Diplothecangia, Distichophylliina, Ebocotrochus, Eburneotrochus, Eckastraea, Edwardsomeandra, Epitrochus, Etalloniopsis, Eugyriopsis, Euphyllidae, Eupsammidae, Eusthenotrochus, Fasciatiphyllia, Fasciseris, Faviina, Favitopsis, Fungiina, Furcophyllia, Gallitellia, Gombertiphyllia, Haplareidae, Hedeliastraea, Heliostylina, Helladophyllia, Heterocoeniina, Houchangocyathus, Ilariosmilia, Isastraeidae, Isphyllastrea, Javanopora, Karatchastraea, Kobycoenia, Lamellomeandra, Lepiconus, Lithodendron, Lupitschia, Mareastraea, Meandriina, Meandrovolzeia, Microsolenina, Miophora, Mioscapophyllia, Miscellosmilia, Molukkia, Monticuliphyllia, Morchellastraea, Ondadiplocteniopsis, Pachysmilia, Pachythecaliina, Palaeophyllia, Palaeoseris, Palaeosmilia, Phylloseriopsis, Pleuropodia, Progonopora, Psammocyathus, Pyramisasteria, Reisocyathus, Reussiphyllia, Rhabdofavia, Rhipidogyrina, Rhopalophyllia, Saeptiphyllia, Sakalavastraeopsis, Sclydolithus, Siderocoenia, Sinasteria, Siniastraea, Smilostyliidae, Solenocoeniidae, Streptocyathopsis, Streptocyathus, Stylinina, Stylophyllina, Thamnasterites, Thigmastrea, Trachyphylliidae, Tropiastraea, Variabilifavia
Ecology: stationary intermediate-level epifaunal microcarnivore-photosymbiotic