A large new mosasaur from the Upper Cretaceous of The Netherlands

Abstract

We report the discovery of a new species of marine reptile, a mosasaur, from the Upper Cretaceous (Maastrichtian) of The Netherlands. Prognathodon saturator sp. nov. is represented by an almost complete skull and much of the postcranial skeleton, and is one of the largest mosasaurs discovered to date. The stout skull and extremely massive jaws are more powerfully built than in any other known mosasaur. Bite marks, the partial disarticulation and scattering of the skeleton, and the presence of associated teeth of Squalicorax and Plicatoscyllium suggest extensive scavenging by sharks.

Soft tissue preservation in a fossil marine lizard with a bilobed tail fin

“…Accompanying this migration is a forward shifting of the abdominal viscera, documented in an exceptionally preserved specimen (LACM 128319; Natural History Museum of Los Angeles County) of the russellosaurine mosasaur Platecarpus 22,52 . Judging from the flattened but otherwise virtually intact rib cage of ERMNH HFV 197, and with additional data/measurements taken from the closely related mosasaurines Prognathodon overtoni 33 and Prognathodon saturator 53 , it is clear that at least in these relatively derived mosasaurs, the anterior body was fairly deep, but quickly narrowed posteriorly, reaching its narrowest point just anterior to the tail fluke (Fig. 6a).…”

Rib fracture in Prognathodon saturator (Mosasauridae, Late Cretaceous)

“…Maastrichtian) of the ENCI-Maastricht B.V. quarry, south of Maastricht, and has been dated at 66,1 million years (Vonhof & Smit, 1996;Dortangs et al, 2002).…”

Sharks eating mosasaurs, dead or alive?

“…The skeleton is rather disarticulated, with the flippers almost entirely missing, a rather disarticulated tail, and only the skull and trunk relatively well preserved. Several ribs display bite marks, with none of them showing any sign of healing (Dortangs et al, 2002). On various occasions, Squalicorax has been implicated in scavenging on mosasaur carcasses (e.g., Schwimmer et al, 1997;Kass, 1999;Everhart, 2004b).…”