Phylogeny of iguanodontian dinosaurs and the evolution of quadrupedality Author Poole, Karen E. text Palaeontologia Electronica 2016 a 30 25 3 1 65 http://dx.doi.org/10.26879/702 journal article 10.26879/702 1094-8074 11063310 RHABDODONTOIDEA new clade name Phylogenetic definition. A stem-based taxon including all taxa more closely related to Zalmoxes robustus and Rhabdodon priscus than to Dryosaurus altus . Unambiguous synapomorphies. The smaller clade found in the parsimony analysis is characterized by four unambiguous synapormorphies: a sub-rectangular orbit (34.1), sinuous ventral edge of the jugal (56.1), caudodorsally extending postacetabular process of the ilium (265.1), and a femur that is straight in lateral view (290.0). The larger Bayesian clade has two unambiguous synapomorphies: maxilla with a broad triangular dorsal process (21.1), and a straight maxillary toothrow in ventral view (26.2). Topology. The parsimony analysis ( Figures 6 , 7 ) recovers a clade containing rhabdodontids, Tenontosaurus , and Muttaburrasaurus ; this is supported by a jackknife value of 23, and Bremer support of 4. The Bayesian analysis ( Figures 6 , 8 ) also finds Tenontosaurus and Muttaburrasaurus as the sister taxa to Rhabdodontidae , but this is included within a larger clade with many Gondwanan taxa ( Kangnasaurus , Anabisetia , Trinisaura , and Talenkauen ) . The basal node of the clade is poorly supported (PP=0.24), though the node supporting Rhabdodontidae , Muttaburrasaurus , and Tenontosaurus has stronger support (PP=0.85).