Mesozoic Era. In a land before time, between approximately 245 and 66 million years ago dinosaurs thrived on Earth. This time was designated as the Mesozoic Era and is divided into three distinct periods; Triassic, Jurassic and Cretaceous. During the Cretaceous period, between approximately 145 to 66 million years ago, dinosaur diversity increased rapidly to include one of the most well-known theropods, the Tyrannosaurus rex. Theropods are two-legged carnivores such as Tyrannosaurus and Velociraptor that likely paved the way for modern birds.
 
The Suciasaurus and Washington. On April 10, 2012, a dinosaur fossil was discovered by two Burke Museum research associates on the shores of Sucia Island State Park in the San Juan Islands. This fossil was identified as a partial femur bone from a theropod dinosaur that lived approximately 80 million years ago, in the late Cretaceous period. It took almost a year to fully excavate the section of fossil from the surrounding rock and re-attach the pieces. The fossil is 16.7 inches long, which the Burke Museum estimates would have been part of a femur measuring more than three feet in length. The area of Sucia Island where the fossil was recovered is from shallow marine rocks of the Cedar District Formation. Presence of fossilized clams lead scientists to estimate the approximate location of where the theropod died to be between Baja California, Mexico, or Northern California. The exact designation of theropod is unknown, yet evidence suggests it may be a species similar to Daspletosaurus. The theropod fossil has been nicknamed the Suciasaurus rex in recognition of the island where it was discovered.
 
Washington is the 37th state to have found a dinosaur fossil. Twelve states and Washington D.C. have designated official state dinosaurs.

The Suciasaurus rex is the state dinosaur of Washington.