Class Enteropneusta (acorn worm)
Parent taxon: Hemichordata according to C. B. Cameron 2016
See also Bulman 1970, Nielsen 2012, Sepkoski 2002 and Zrzavy et al. 1998
Sister taxon: Pterobranchia
Subtaxa: Harrimaniidae Spartobranchus Spengelidae
Distribution:
• Jurassic of Italy (1 collection)
• Carboniferous of United States (2: Illinois)
• Marjumian of United States (1: Utah)
• Cambrian of Canada (1: British Columbia)
Total: 5 collections including 6 occurrences