dicraeosaurid

Dicraeosauridae is a family of theropod dinosaurs that lived during the Late Cretaceous period, approximately 99 to 93 million years ago. They are known from fossils found in what is now North America, particularly in the Hell Creek Formation of Montana and South Dakota. Dicraeosaurids are characterized by their distinctive, elongated skulls with a long, narrow snout, and a unique set of teeth that are adapted for crushing plant material.

The family includes two genera, Dicraeosaurus and Orodromeus. Dicraeosaurus is the better-known of the two, with several species described, including D. saturatus and D. altus. Orodromeus, on the other hand, is known from a single species, O. mcleodii, which is distinguished by its smaller size and more robust build compared to Dicraeosaurus.

Dicraeosaurids are believed to have been herbivorous, feeding on a diet of soft plants and fruits. Their elongated skulls and specialized teeth suggest that they were well-adapted for grazing and browsing. The family's evolutionary history is not well understood, but they are thought to have been part of the larger group of theropod dinosaurs that diversified during the Late Cretaceous.

Despite their interesting adaptations, dicraeosaurids are not as well-known as some other theropod dinosaurs, such as Tyrannosaurus or Velociraptor. However, their unique features and the insights they provide into the diversity of Late Cretaceous ecosystems make them an important group for paleontologists to study.