Strophomenata - Strophomenida - Syndielasmatidae
Parent taxon: Plectambonitoidea according to A. Williams et al. 2000
Sister taxa: Aegiromenidae, Allwynellidae, Alwynellidae, Bimuriidae, Christianiidae, Grorudiidae, Hesperomenidae, Leptellinidae, Leptestiidae, Paucicostella, Plectambonitidae, Sowerbyellidae, Strophodontidae, Taffiidae, Tafflidae, Xenambonitidae, Anoptambonitidae
Subtaxa: Sowerbyites Syndielasma
Type: Syndielasma
Ecology: stationary epifaunal suspension feeder
Distribution:
• Whiterockian of United States (2: Nevada collections)
• Arenig of China (1)
• Ordovician of Australia (25), Canada (1: Northwest Territories), Ireland (1), Norway (1), the United Kingdom (1), United States (24: Kentucky, Nevada, Oklahoma, Tennessee, Virginia)
Total: 56 collections including 57 occurrences