Parent taxon: Blastozoa according to S. L. Sheffield and C. D. Sumrall 2019
See also Beaver et al. 1967, Bockelie 1984 and Sheffield and Sumrall 2018
Sister taxa: Asteroblastida, Blastoidea, Crinoidea, Diploporita, Eocrinoidea, Lepidocystoidea, Parablastoidea, Paracrinoidea, Rhombifera, Rhombifera, Soluta, Sphaeronitida
Subtaxa: Dactylocystidae Eumorphocystidae Glyptosphaeritidae Gomphocystitidae Protocrinitidae
Distribution:
• Devonian of United States (1: Kentucky collection)
• Silurian of United States (13: California, Illinois, Indiana, Iowa, Wisconsin)
• Uhaku of Lithuania (1)
• Ordovician of the Czech Republic (6), Estonia (4), Iran (1), Latvia (1), Lithuania (1), Sweden (1), United States (10: Illinois, Iowa, Iowa, Minnesota, Oklahoma, Tennessee, Virginia)
• Tremadoc of the Czech Republic (3)
Total: 42 collections including 47 occurrences