Clint Boyd, Ph.D., assistant professor South Dakota School of Mines and Technology, and colleagues presented a new dinosaur species found in Utah that shows the first evidence that crocodyliforms ate young dinosaurs in the open access peer reviewed journal Public Library of Science on Feb. 28, 2013.
The new species of herbivorous dinosaur - Kaiparowits hypsilophodontid - was discovered in four locations in the Grand Staircase-Escalante National Monument in southern Utah. All the fossils date to the late Cretaceous period - between 100 to 66 million years ago. The pubic anatomy indicates this is a never before seen species of dinosaur.
The vertebral development shown in all the specimens recovered indicate that all the fossils come from juvenile dinosaurs. The largest specimen was a little more than six feet in length.
Most importantly, the Kaiparowits hypsilophodontid fossils are the only known evidence that early crocodiles - crocodyliforms - ate young dinosaurs. Bite marks on the dinosaur fossils are consistent with the size and tooth structure of crocodyliforms known to have existed in the area at the same time.
The evidence is further corroborated by the discovery of a crocodyliform tooth fragment in one of the dinosaur fossils.
This discovery is congruent with the large water system that covered a majority of Utah at the time and is consistent with other discoveries that show evidence that large Cretaceous mammals ate juvenile dinosaurs.
Citation: Boyd CA, Drumheller SK, Gates TA (2013) Crocodyliform Feeding Traces on Juvenile Ornithischian Dinosaurs from the Upper Cretaceous (Campanian) Kaiparowits Formation, Utah. PLoS ONE 8(2): e57605. doi:10.1371/journal.pone.0057605