The Euornithocheira are a group of pterosaurians belonging to the Ornithocheiroidea.
The British paleontologist David Unwin noted in his cladistic analyzes that the Ornithocheiridae and the Pteranodontidae together formed a clade, a monophyletic descent group. In 2003 he named this group as the Euornithocheira ("true ornithochiren"). Unwin defined the clade as: the group consisting of the last common ancestor of Ornithocheirus mesembrinus and Pteranodon longiceps and all descendants.
Unwin gave the following three synapomorphics, shared new features, of the group: the posterior edge of the fenestra antorbitalis is hollow; the bottom of the eye box is flat; the joints between the raven bones and the breastbone lie side by side rather than sequentially.
The Euornithocheira are the sister group of Istiodactylus and must have separated themselves in early chalk. They consist largely of very large shapes that have been strongly adapted to the glider. Literature
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