Pteranodontia

Pteranodontians Temporal range: Early Cretaceous - Late Cretaceous, 127–66 Ma PreЄ Є O S D C P T J K Pg N
Mounted skeleton Pteranodon longiceps
Fossil specimen of Nyctosaurus gracilis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	†Pterosauria
Suborder:	†Pterodactyloidea
Clade:	†Ornithocheiroidea
Clade:	†Pteranodontia Marsh, 1887
Subgroups
†Nyctosauridae †Pteranodontoidea †Ornithocheiromorpha †Pteranodontidae
Synonyms
Euornithocheira Unwin, 2003

Pteranodontia is an extinct group of ornithocheiroid pterosaurs that lived from the Early Cretaceous to the Late Cretaceous (middle Barremian to middle Campanian stages) of Asia, Europe, North America and South America.^[1]

Locomotion

Pteranodontians, like other pterosaurs, are considered to have been skilled fliers as well as adept at moving on the ground. Evidence from footprints shows that most pterosaurs did not sprawl their limbs to a large degree, as in modern reptiles, but rather held the limbs relatively erect when walking, like dinosaurs. While no pteranodontian footprints are known, it is likely that they also walked erect.^[2] Among pterosaurs, pteranodontians had unusually uneven limb proportions, with the forelimbs much longer than the hind limbs. This would likely have required them to use unique modes of locomotion when on the ground compared to other pterosaurs. It is possible that pteranodontians ran (but not walked) bipedally, or that they used a hopping gait.^[2] Pterosaur researcher Mike Habib has noted that the limbs proportions of pteranodontians like Anhanguera are consistent with hopping.^[3]

Pteranodontians were among the last of the world's pterosaur faunas. The species Piksi barbarulna and a few potential pteranodontids and nyctosaurs have all been found dating from the Campanian to the Maastrichtian ages of the Late Cretaceous period.^[4]

Classification

Pteranodontia was originally named by O.C. Marsh in 1876. In 2003, it was given a phylogenetic definition by David Unwin as the common ancestor of Pteranodon and Nyctosaurus plus all its descendants. Though Marsh had originally named this group based on the shared absence of teeth in those species, most analyses show that all of the traditional "ornithocheiroid" pterosaurs are also members of this clade.

In 2003, Alexander Wilhelm Armin Kellner defined the clade Pteranodontoidea as the last common ancestor of Anhanguera, Pteranodon and all its descendants. Ornithocheiroidea is sometimes considered to be the senior synonym of Pteranodontoidea, however its depends on it definition. Ornithocheiroidea was originally defined as an apomorphy-based taxon by Christopher Bennett in 1994. Later, Kellner (2003) redefined it to represent the node of Anhanguera, Pteranodon, Quetzalcoatlus and Dsungaripterus.^[5] Later, David Unwin (2003) suggested a different definition, the node that contains Pteranodon longiceps and Istiodactylus latidens, thus making Pteranodontoidea a junior synonym of Ornithocheiroidea.^[6] Brian Andres (2008, 2010, 2014) in his analyses, converts Ornithocheiroidea using the definition of Kellner (2003) to avoid this synonymy.^[7]

Classification

Below is a cladogram showing the results of a phylogenetic analysis presented by Andres & Myers, 2014.^[8]

"Wyomingopteryx"

The name "Wyomingopteryx" appears in a painting of Morrison prehistoric animals by Robert Bakker. However, this binomen is a nomen nudum, and it is possible that Bakker may have intended to coin "Wyomingopteryx" for the Istiodactylus-like specimen TATE 5999 because that specimen is found in Wyoming.^[9][10]

References