The morphology ofCanninginopsisCookson & Eisenack 1962 has been re-assessed through examination of the type species,C. denticulataCookson & Eisenack 1962, from the Mid Cretaceous of the Perth Basin, andC. bretonicasp. nov. from the Late Cretaceous of the Perth and Gippsland Basins. The genus now includes forms with a greater variation in the ventrodorsal outline of the autocyst, surface sculpture, and distribution and morphology of characters marking the paratabulation. The widespread distribution of taxa within the genus combined with their distinctive morphologies and restricted stratigraphic ranges make them important index species in the Australian Cretaceous.