| Tapejarids Temporal range: Early Cretaceous, 125–108 Ma |
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| Reconstructed skeleton of Tapejara wellnhoferi | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | †Pterosauria |
| Suborder: | †Pterodactyloidea |
| Superfamily: | †Azhdarchoidea |
| Family: | †Tapejaridae Kellner, 1989 |
| Type species | |
| †Tapejara wellnhoferi Kellner, 1989 |
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| Subfamilies | |
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†Chaoyangopterinae? |
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| Synonyms | |
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Thalassodromidae? Kellner & Campos, 2007 |
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Tapejaridae (meaning "the old beings") are a family of pterodactyloid pterosaurs from the early Cretaceous period. Members are currently known from Brazil and China, where the most primitive genera are found, indicating that the family has an Asian origin.[1]
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Tapejarids were small to medium-sized pterosaurs with several unique, shared characteristics, mainly relating to the skull. Most tapejarids possessed a bony crest arising from the snout (formed mostly by the premaxillary bones of the upper jaw tip). In some species, this bony crest is known to have supported an even larger crest of softer, fibrous tissue that extends back along the skull. Tapejarids are also characterized by their large nasoantorbital fenestra, the main opening in the skull in front of the eyes, which spans at least half the length of the entire skull in this family. Their eye sockets were small and pear-shaped.[2] Studies of tapejarid brain cases show that they had extremely good vision, more so than in other pterosaur groups, and probably relied nearly exclusively on vision when hunting or interacting with other members of their species.[3] Tapejarids had unusually reduced shoulder girdles that would have been slung low on the torso, resulting in wings that protruded from near the belly rather than near the back, a "bottom decker" arrangement reminiscent of some planes.[3]
Tapejaridae may be composed of two subfamilies: a Tapejarinae of "Huaxiapterus" corollatus, Sinopterus, Tapejara, Tupandactylus, and a Thalassodrominae of Thalassodromeus and Tupuxuara.[4] Some studies, such as one by Lü and colleagues in 2008, have found that the thalassodromines are more closely related to the azhdarchids proper than to the tapejarids,[5] and have placed them in their own family (which has sometimes been referred to as Tupuxuaridae,[6] though Thalassodrominae was named first[4]). At least one study has also found that the Chaoyangopteridae, often found to be closer to azhdarchids, represent a lineage within the Tapejaridae, more closely related to the tapejarines than to the thalassodromines. Felipe Pinheiro and colleagues (2011) reclassified the group as a subfamily of Tapejaridae, Chaoyangopterinae, for this reason.[2]
The exact relationships of tapejarids to one another and to other azhdarchoid pterosaurs has historically been unclear, with different studies producing significantly different cladograms (family trees). It is also unclear exactly which pterosaurs belong to the Tapejaridae; some researchers have found the thalassodromines and chaoyangopterines to be members of this family,[4][2] while other studies have found them to be more closely related to the azhdarchids (in the clade Neoazhdarchia).[7] Some studies have even allowed the possibility that the "tapejarids" as traditionally thought of are paraphyletic, that is, they may not form a natural group but instead represent sequential branches of the tree leading to the more advanced neoazhdarchians.[7] Below are two alternate cladograms: the first, presented by Felipe Pinheiro and colleagues in 2011, shows the tapejarids as a monophyletic clade including the thalassodromines and chaoyangopterines. The second, presented by Dave Martill and Darren Naish in 2006, shows them as a paraphyletic grade.
| Azhdarchoidea |
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| Azhdarchoidea |
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