Lingulata - Acrotretida - Scaphelasmatidae
Parent taxon: Acrotretoidea according to J. Hansen and L. E. Holmer 2011
See also Popov 2000 and Williams et al. 2000
Sister taxa: Acrothyra, Acrotretidae, Ceratretidae, Craniotreta, Curticiidae, Eoconulidae, Ephippelasmatidae, Hadrotreta, Schizotretoides, Torynelasmatidae, Acrotetidae
Subtaxa: Artiotreta Eoscaphelasma Rhysotreta Scaphelasma Tobejalotreta
Ecology: stationary epifaunal suspension feeder
Distribution:
• Silurian of Australia (5 collections), United States (3: Oklahoma)
• Uhaku of Sweden (5)
• Chazyan of United States (1: Alabama)
• Ordovician of Argentina (3), Australia (4), Canada (1: Newfoundland and Labrador), Estonia (14), Ireland (2), Kazakhstan (3), Norway (8), Sweden (24), United States (1: Iowa)
• Cambrian of Kazakhstan (13), Mexico (1)
Total: 88 collections including 99 occurrences