Silesauridae
Silesauridae is an extinct family of Triassic dinosauriforms. It is most commonly considered to be a clade of non-dinosaur dinosauriforms, and the sister group of dinosaurs. Some studies have instead suggested that most or all silesaurids comprised an early diverging clade or a paraphyletic grade within ornithischian dinosaurs. Silesaurids have a consistent general body plan, with a fairly long neck and legs and possibly quadrupedal habits, but it is important to note that most silesaurids are heavily fragmentary nonetheless. Furthermore, they occupied a variety of ecological niches, with early silesaurids (such as "Lewisuchus") being carnivorous and later taxa  (such as "Kwanasaurus") 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. Classification. Silesauridae is typically considered the sister group to Dinosauria. The group was named in 2010 by Max C. Langer "et al". They defined it as a branch-based clade of all archosaurs closer to "Silesaurus opolensis" than to either "Heterodontosaurus tucki" or "Marasuchus lilloensis". At around the same time, Sterling J. Nesbitt "et al". (2010) independently named Silesauridae as a node-based clade consisting of "Lewisuchus", "Silesaurus", their last common  ancestor and all their descendants. 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). The fossils range in age from the Anisian to the Norian stages of the Triassic, about 245 to 203 million years ago. The cladogram below follows the phylogenetic analysis of basal  ornithodirans conducted by Christian Kammerer, Sterling Nesbitt and Neil Shubin (2012) with clade terminology from Cau (2018) and Martz and Small (2019). A large phylogenetic analysis of early dinosaurs and dinosauromorphs carried out by Matthew Baron, David Norman and Paul Barrett (2017) and published in the journal "Nature" recovered Silesauridae as a monophyletic sister group to Dinosauria. The study also recovered the taxon "Agnosphitys" within the clade Silesauridae, close to "Lewisuchus" and its synonymous taxon "Pseudolagosuchus".