Class Aculifera Blumrich 1891 (mollusk)
Parent taxon: Sachitida according to J. Vinther et al. 2017
Sister taxa: Adversella, Carubacgutes, Halkierioidea, Hippopharangites, Miriella, Quadrochites, Siphogonuchitidae, Siphogonuchitoidea, Orthrozanclidae, Australohalkieria, Wiwaxia
Subtaxa: Halkieriidae Inughuitoconus
Ecology: epifaunal grazer
Distribution:
• Cambrian of Australia (46 collections), Canada (12: Newfoundland and Labrador, Nova Scotia), China (113), Greenland (7), Kazakhstan (9), Kyrgyzstan (2), Mongolia (2), the Russian Federation (27), Turkey (1), United States (6: Massachusetts, New York)
• Placentian of United States (1: Massachusetts)
Total: 226 collections including 311 occurrences