Range data is plotted against composite lithostratigraphy and age model. Includes new data from this study (see Methods and Supplementary Figs 1–4), and from refs 16, 18 (see also Supplementary Fig. 5). Separated into bivalves (B) (1–32), gastropods (G) (33–51), and cephalopods (A and N) (52–66), with taxa ordered by first appearance in the composite section. Range extensions calculated based on a literature review of molluscan occurrences from underlying formations (Supplementary Table 1), in addition to collections from overlying Paleocene strata24,44. Also illustrated are the stratigraphic ranges of marine reptile fossils (MR), lamniform shark vertebrae (S), echinoid spines (E) and serpulid worm tubes (Rotularia .spp (R) in the composite section. Age model is derived from ref. 23 (see Supplementary Fig. 1 for detailed explanation). Time scale is based on Sr isotope chemostratigraphy (italicized A–C)68 and magnetostratigraphy17, updated with ages from the Geological Time Scale 2012 (ref. 69) and using the K–Pg boundary datum. G, glauconite-rich intervals. S, Sobral Formation. See Supplementary Note 1 for details of species identifications.