Diet: Quaesitosaurus was an herbivore (it ate only plants) that had peg-like teeth. It must have eaten a tremendous amount of plant material each day to sustain itself. It swallowed leaves whole, without chewing them, and may have had gastroliths (stomach stones) in its stomach to help digest tough plant material. The blunt teeth were useful for stripping foliage.

Anatomy: This dinosaur probably had good hearing. Quaesitosaurus' skull was long and had a wide snout and a large ear opening. The peg-like teeth were adapted for eating soft food, perhaps aquatic plants. Quaesitosaurus may have been about 75 feet (23 m) long.

Name: Quaesitosaurus (meaning "abnormal or extraordinary lizard") was named by Kurzanov and Bannikov in 1983.

Fossils and Environment: Quaesitosaurus is known only from a partial skull found in the southeastern Gobi desert, Mongolia. This environment was semi-arid during the Mesozoic Era.