Fig. 4: Palaeobiogeography of Deinosuchus spp.

(A) Distribution of Deinosuchus riograndensis and D. schwimmeri³ during the Campanian around the Western Interior Seaway (WIS). (B) parsimony ancestral state reconstruction (equal branch length) of osmoregulation in Crocodylia and close relatives using presence/absence of salt glands, stable isotopes, and coastal marine occurrences as proxies^{11,13,14,15,17,35,36,37,38,39,40,42,44,120}. The topology is from the present study except for ‘thoracosaurs’ for which we follow a more appropriate tip-dated work⁴¹. The analysis suggests potential plesiomorphic saltwater-tolerance for Deinosuchus and Crocodylia with early loss in Alligatoroidea. The distribution of Deinosuchus may be explained by dispersal across the WIS. Map is redrawn from¹¹⁸, early to late Campanian. Distribution of Deinosuchus spp. follows^3,11,17 and references therein.