A fossil champsosaur population from the high Arctic: Implications for Late Cretaceous paleotemperatures. 2007. D. Vandermark, J. A. Tarduno, and D. B. Brinkman. Palaeogeography, Palaeoclimatology, Palaeoecology 248: 49-59.
This dominance of subadults is similar to that seen from low latitude sites and suggests that the champsosaur population was a well-established facet of the ecological community. Because of the sensitivity of juveniles to ice formation, the make-up of the Arctic champsosaur population further indicates that the Late Cretaceous (Coniacian–Turonian) saw an interval of extreme warmth and low seasonality.
The Coniacian–Turonian date makes these choristoderes amongst the earliest in North America, apart from the Jurassic Cteniogenys and a single limb bone from the mid-Cretaceous.