The Caelidracones is a group of

pterosaurs Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 to ...

. The

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

Caelidracones was defined in 2003 by David Unwin as the group consisting of the last common ancestor of '' Anurognathus ammoni'' and ''

Quetzalcoatlus northropi ''Quetzalcoatlus'' is a genus of pterosaur known from the Late Cretaceous period of North America (Maastrichtian stage); its members were among the largest known flying animals of all time. ''Quetzalcoatlus'' is a member of the Azhdarchidae, a ...

'', and all its descendants. The name Caelidracones means "sky dragons" from Latin ''caelum'', "heaven", and ''draco'', "dragon" and is a reference to Harry Govier Seeley's 1901 book, ''Dragons of the Air''.

Classification

In Unwin's original classification, the Caelidracones were considered the

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and t ...

of the

Dimorphodontidae Dimorphodontidae (or dimorphodontids) is a group of early "rhamphorhynchoid" pterosaurs named after '' Dimorphodon'', that lived in the Late Triassic to Early Jurassic. While fossils that can be definitively referred to the group are rare, dimorp ...

within the Macronychoptera and consist of the Anurognathidae and the

Lonchognatha Novialoidea (meaning "new wings") is an extinct clade of macronychopteran pterosaurs that lived from the latest Early Jurassic to the latest Late Cretaceous (early Toarcian to late Maastrichtian ageBarrett, P. M., Butler, R. J., Edwards, N. P., ...

. More recent studies of pterosaur relationships have found anurognathids and pterodactyloids to be sister groups, which would limit Caelidracones to just those two clades. Below is a cladogram showing the results of a phylogenetic analysis presented by Longrich, Martill, and Andres, 2018. This study found the two traditional groupings of ctenochasmatoids and kin as an early branching group, with all other pterodactyloids grouped into the Eupterodactyloidea.Longrich, N.R., Martill, D.M., and Andres, B. (2018)
Late Maastrichtian pterosaurs from North Africa and mass extinction of Pterosauria at the Cretaceous-Paleogene boundary.
''PLoS Biology'', 16(3): e2001663.

References

{{Taxonbar, from=Q2011078 Monofenestratans Oxfordian first appearances Maastrichtian extinctions