ANKYLOPOLLEXIA, 1986

Poole, Karen E., 2016, Phylogeny of iguanodontian dinosaurs and the evolution of quadrupedality, Palaeontologia Electronica (a 30) 25 (3), pp. 1-65 : 19

ANKYLOPOLLEXIA Sereno, 1986

Phylogenetic definition. The least inclusive clade containing Camptosaurus dispar ( Marsh, 1879) , Uteodon aphanoecetes ( Carpenter and Wilson 2008) , and Parasaurolophus walkeri Parks, 1922 (emended from Sereno, 1986).

Unambiguous synapomorphies. Ankylopollexia is characterized by nine unambiguous synapomorphies: deltoid ridge of the scapula close to parallel to the long axis of the scapula (198.0), humerus with a well-developed deltopectoral crest (212.0), ulna with a flange on the proximal end that wraps around the lateral edge of the radius (219.1) some fusion of the carpals (227.1), manual digit I oriented at least 45 degrees from the antebrachial axis (232.1), metacarpal I short and block-like (233.1), ungual of manual digit I subconical (241.1), brevis fossa of ilium not well defined by a lateral lip (259.0), ossified epaxial and hypaxial tendons arranged in a double-layered lattice (323.1).

Topology. This is a well-supported clade, with a Jackknife value of 35 and Bremer support of 6 in the parsimony analysis ( Figure 7 ), and a posterior probability of 0.91 in the Bayesian tree ( Figure 8 ). In both topologies, the most basally branching taxon is Uteodon , and Camptosaurus is recovered as the sister to Styracosterna. These two genera are the only non-styracosternan ankylopollexians.

Figures

FIGURE 7. Time scaled parsimony tree, showing assigned age ranges and broad-scale geographic data. Jackknife values above 20 (with 10% chance of character removal) are shown above and to the left of their respective nodes. Bremer supports above one are shown below and to the left of their respective nodes, and bolded.

FIGURE 8. Maximum Clade Credibility tree produced by Bayesian analysis. Posterior probabilities are shown to the left of their nodes. The geologic timescale is shown across the top. Tips represent the average age found for each OTU across all sampled trees.