Parent taxon: Cladida according to G. D. Webster 1990
See also Mao et al. 2018, Ubaghs et al. 1978, Webster et al. 2009 and Webster and Webster 2012
Sister taxa: Aaglacrinus, Aithriocrinus, Ampelocrinida, Apektocrinidae, Bicidiocrinus, Briseocrinus, Cathetocrinus, Contignatindocrinus, Cyathocrinacea, Dendrocrinina, Dimerocrinites anticostiensis, Eopilidiocrinus, Eucladida, Flexibilia, Goniocrinus, Harmostocrinus, Idaeumocrinus, Kanabinocrinus, Kansacrinus, Kooptoonocrinus, Lanecrinus, Lekocrinus, Lophocrinacea, Manicrinus, Mathericrinus, Menniscocrinus, Miatschkovocrinus, Nacocrinus, Nuxocrinus, Parascytalocrinus, Porocrinoidea, Poteriocrinitina, Premanicrinus, Pskovicrinus, Pulaskicrinus, Pumilindocrinus, Pyrenocrinus, Rimosidocrinus, Saccosompsis, Sardinocrinus, Scammatocrinus, Texacrinacea, Treocrinus, Wetherbyocrinus, Worthenocrinus
Subtaxa: Eupachycrinidae Phanocrinidae Ulocrinidae
Type: Cromyocrinus
Ecology: stationary intermediate-level epifaunal suspension feeder
Distribution:
• Permian of United States (1: Nevada collection)
• Carboniferous of the United Kingdom (10), United States (59: Alabama, Arkansas, Illinois, Indiana, Kentucky, Oklahoma, Pennsylvania, Tennessee)
Total: 70 collections including 104 occurrences