The left exterior nasal opening of the mosasaur's skull. Although well adapted to marine life, mosasaurs were still air breathers and probably breathed through their nasal openings when they surfaced. The business end of a mosasaur, showing the extension of the premaxilla over the most anterior teeth which is also typical of Tylosaurs. In some fossil remains, the premaxilla shows evidence of being used as a 'battering ram'. The joint between the premaxilla and maxilla is shown between the second and third teeth on the upper jaw.
Pits shown in the upper and lower jaws are probably openings for blood vessels and nerves.
The middle teeth in the upper and lower jaws. Although shaped like sharp cones, the teeth do not have much of a cutting edge. In most mosasaurs, the teeth were used primarily for seizing and crushing prey, which was then swallowed whole. The posterior teeth in the upper and lower jaws. Stratigraphically, the remains were found 2.7 m. below the base of Marker Unit 10 and within the upper portion of the biostratigraphic zone of Clioscaphites vermiformis .