Figure 8 in The Paleocene cephalopod fauna from Pebble Point, Victoria (Australia) - fulcrum between two Eras

Figure 8. Hypothesized generic level phylogeny of a portion of post-Jurassic nautilids. Eutrephoceras spp predate Nautilus and were not involved in subsequent generic evolution. Nautilus appears in either the Late Jurassic or Early Cretaceous, based on unpublished observations of P. Ward in the British Museum, and gives rise to subsequent genera Cimomia, Hercoglossa, Aturoidea, Aturia, and Deltoidonautilus. Nautilus also gives rise to Allonautilus in either Pliocene or Pleistocene.