dinosauriforms. It is most commonly considered to be a clade of non-dinosaur dinosauriforms, and the sister group of dinosaurs.[1][2][3][4][5] Some studies have instead suggested that most or all silesaurids comprised an early diverging clade or a paraphyleticgrade within ornithischian dinosaurs.[6][7][8][9] Silesaurids have a consistent general body plan, with a fairly long neck and legs and possibly quadrupedal habits, but most silesaurids are heavily fragmentary nonetheless. Furthermore, they occupied a variety of ecological niches, with early silesaurids (such as Lewisuchus)[10] being carnivorous and later taxa (such as Kwanasaurus)[11] having adaptations for specialized herbivory. As indicated by the contents of referred coprolites, Silesaurus may have been insectivorous, feeding selectively on small beetles and other arthropods.[12]
Classification
Silesauridae is typically considered the
Marasuchus lilloensis.[13] At around the same time, Sterling J. Nesbittet al. (2010) independently named Silesauridae as a node-based clade consisting of Lewisuchus, Silesaurus, their last common ancestor and all their descendants.[1] Currently, both definitions encompass the same group of animals. Nesbitt et al. noted that the earlier definition by Langer et al. did not include a diagnosis, and so was not sufficient to create a ranked family-level name according to the ICZN. Therefore, the family Silesauridae is attributed to Nesbitt et al. (2010) while the clade Silesauridae is attributed to Langer et al. (2010).[3]
A 2022 study by Norman and colleagues instead found silesaurs to be a
paraphyletic group on the branch leading to traditional Ornithischia. The cladogram below is based on their study.[15] This topology is almost identical to the one recovered by Müller & Garcia (2020)[9]
