Eoraptor lunensis (Sereno et al. 1993) is a basal phytodinosaur, derived from a sister to Herrerasaurus and was a sister to or congeneric with Panphagia. it is a basal phytodinosaur, basal to Pampadromaeus and Leyesaurus.

Sereno et al. (2013) report, “The first dentary tooth in Eoraptor, in addition, is retracted from the anterior end of the dentary, which is marked by a pair of conspicuous neurovascular foramina—features that characterize plant-eating basal sauropodomorphs. These features and the short length of the lower jaws suggest that there may have been a small keratinous beak at the anterior end of the lower jaws in Eoraptor and Panphagia. We have yet to discover a carnivorous dinosaur—or for that matter a carnivorous extant lizard—that has retained teeth for predation and that has inset these teeth from the anterior end of the lower or upper jaws (Sereno, 2012). This favors Eoraptor as a herbivore.”

Panphagia protos Martinez and Alcobar (2009) described a small, basal Triassic dinosaur possibly congeneric with Eoraptor. Panphagia protos has seniority. The scapula is more robust in Panphagia. Both nested between theropods and phytodinosaurs. The pubis is slender in lateral view, but not in anterior view. This is the first clue I've seen as to the origin of the retroverted slender pubis in Ornithischia.

Martínez RN and Alcober OA 2009. A basal sauropodomorph (Dinosauria: Saurischia) from the Ischigualasto Formation (Triassic, Carnian) and the early evolution of Sauropodomorpha (pdf). PLoS ONE 4 (2): 1–12. doi:10.1371/journal.pone.0004397. PMC 2635939. PMID 19209223. online article

Sereno PC, Forster CA, Rogers RR and Moneta AM 1993. Primitive dinosaur skeleton form Argentina and the early evolution of the Dinosauria. Nature 361, 64-66.

Sereno PC, Martínez RN and Alcober OA 2013. Osteology of Eoraptor lunensis (Dinosauria, Sauropodomorpha). Basal sauropodomorphs and the vertebrate fossil record of the Ischigualasto Formation (Late Triassic: Carnian-Norian) of Argentina. Journal of Vertebrate Paleontology Memoir 12: 83-179 DOI:10.1080/02724634.2013.820113

wiki/Panphagia

wiki/Eoraptor