Parent taxon: Trimerellida according to A. Williams et al. 2000
See also Cocks 2019
Sister taxon: Adenus
Subtaxa: Adensuidae Trimerellidae Ussuniidae
Ecology: stationary epifaunal suspension feeder
Distribution:
• Niagaran of United States (2: Indiana, Ohio collections)
• Silurian of Australia (2), Canada (23: Manitoba, New Brunswick, Northwest Territories, Nunavut, Ontario), China (3), Czechia (2), the Russian Federation (4), Sweden (4), the United Kingdom (2), United States (17: Illinois, Indiana, Iowa, Michigan, Wisconsin)
• Arenig of Spain (1)
• Ordovician of Australia (16), Canada (10: Manitoba, Ontario, Québec), China (5), Kazakhstan (3), Norway (1), the Russian Federation (2), the United Kingdom (6), United States (1: Maine)
Total: 104 collections including 117 occurrences