Atelostomata

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Kingdom: Animalia
Subregnum: Eumetazoa
Cladus: ParaHoxozoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Echinodermata
Subphylum: Eleutherozoa
Superclassis: Cryptosyringida
Classis: Echinoidea
Subclassis: Euechinoidea
Superordo:
Ordines: Cassiduloida - Spatangoida

Unplaced genera (1): Absurdaster

• Baker, A.N.; Rowe, F.W.E. 1990: Atelostomatid sea urchins from Australian and New Zealand waters (Echinoidea : Cassiduloida, Holasteroida, Spatangoida, Neoplampadoida). Invertebrate taxonomy, 4(2): 281–316. DOI: 10.1071/IT9900281
• Kroh, A.; Lukeneder, A.; Gallemí, J. 2014: Absurdaster, a new genus of basal atelostomate from the Early Cretaceous of Europe and its phylogenetic position. Cretaceous research, 48: 235–249. DOI: 10.1016/j.cretres.2013.11.013 ZooBank