Alternative spelling: Somasteroida
Full reference: W. K. Spencer. 1951. Early Palaeozoic starfish. Philosophical Transactions of the Royal Society of London, series B 235(B623):87-129
Parent taxon: Asterozoa according to D. B. Blake 2013
See also Blake 1989, Blake 2018, Blake and Guensburg 1993, Dean Shackleton 2005, Hunter and Ortega-Hernández 2021, Owen 1965, Sepkoski 2002, Spencer 1951 and Spencer and Wright 1966
Sister taxa: Asteroidea, Catervaparmasteridae, Eopentaroida, Falloasteridae, Ophiuroidea, Phragmactinidae, Stenuroidea, Auluroidea
Subtaxa: Archegonaster Archegonasteridae Catervaparmaster Chinianasteridae Goniactinida
Distribution:
• Ordovician of the Czech Republic (1 collection), France (3), Morocco (1), the United Kingdom (1), United States (1: Nevada)
• Arenig of France (1)
Total: 8 collections including 11 occurrences