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
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.