Historically, numerous teeth have been attributed to various dromaeosaurid and troodontid taxa with known body fossils from only older formations, including "Dromaeosaurus", "Saurornitholestes", and "Troodon". However, in a 2013 study, Evans "et al." concluded that there is little evidence for more than a single dromaeosaurid taxon, "Acheroraptor", in the Hell Creek-Lance assemblages, which would render these taxa invalid for this formation. This was disproved in a 2015 study, DePalma "et al.", when they described the new genus "Dakotaraptor", a large species of dromaeosaur. Fossilized teeth of various troodontids and coelurosaurs are common throughout the Hell Creek Formation; the best known examples include "Paronychodon", "Pectinodon" and "Richardoestesia", respectively.