You are here Name: Gryposaurus monumentensis (Pronunciation:
GRIP-oh-SORE-us MAHN-you-men-TEN-siss) Age: Late Cretaceous (~76
million years ago) Where It's Found in Utah: Kane and Garfield
counties, Grand Staircase-Escalante National Monument, Utah.
Geologic Formation: Kaiparowits Formation (middle unit)
Classification: Ornithischia – Ornithopoda – Hadrosauridae -
Hadrosaurinae Description: Hadrosaurids are often referred to as
“duck-billed” dinosaurs because the front of their skull
resembles a bill of a duck. Even the name Gryposaurus means
“hooked beak lizard.” “Monumentensis” gives credit to Grand
Staircase-Escalante National Monument in southern Utah where
these animals were found. There are two types of hadrosaurs:
those without crests, such as Gryposaurus monumentensis, and
those with crests on top of their heads, called lambeosaurines.
Gryposaurus monumentensis is unique compared with other species
of Gryposaurus in that it the front part of the “beak” rises at
a steeper angle. Three to four species o