Kritosaurus novajovius
Upper Aguja Formation
Brewster County, Texas, U.S.A
Upper Cretaceous - Campanian
70 Million Years Ago
Specimen size: approximately .5cm
Kritosaurus was a Hadrosaurid ground dwelling herbivorous dinosaur that is only known by a partial skull and lower jaw( Holotype AMNH 5799, an incomplete skull consisting of partial predentary, nearly complete dentaries, partial left and nearly complete right surangular, right splenial, and angular).
It's estimated that Kritosaurus length was 9 meters (30 feet) and its weight was 4 tonnes (4.4 short tons).
As a hadrosaurid, Kritosaurus would have been a large bipedal/quadrupedal herbivore, eating plants with a sophisticated skull that permitted a grinding motion analogous to chewing. Its teeth were continually replacing and packed into dental batteries that contained hundreds of teeth, only a relative handful of which were in use at any time. Plant material would have been cropped by its broad beak, and held in the jaws by a cheek-like organ. Feeding would have been from the ground up to ~4 meters (13 ft) above.