Tupandactylus

*Tupandactylus* is an extinct genus of tapejarid pterodactyloid pterosaur that lived in Brazil during the Early Cretaceous.

## Description

*T. imperator* is known from 2 full skulls: MCT 1622-R (a skull and partial mandible) and CPCA 3590 (a mandible). The holotype was found in the Crato Formation at the Aptian-Albian boundary, 112 million years ago. This was initially named as a species of *Tapejara*. It has a toothless skull with a prominent sagittal crest that is bony at the base with a tall bony rod extending at front and back of of it. Most of the crest was made of soft tissue or keratin, which was supported by such struts.

The second specimen was described in 2011, and has an asymmetrical keel on the mandibular tip underside. In 2021, a very complete *T. navigans*, GP/2E 9266, was described, suggesting the two species may have been sexually dimorphic morphs of the same species; they caution further study is required to examine the alleged differentiation. This specimen also showed the crest was very different than assumed, being taller, less wide and bearing a forward point. They also found all known skull material is incomplete, as most of the crest is broken off. This specimen was recovered when police raided a fossil dealer's storage, it was first leaked in news articles weeks before the final paper would be formally published.

Both species are supposed differentiated from differing crests, likely used for display like toucans. *T. navigans* lacks the prong found in *T. imperator*, having a taller crest. Soft tissue finds the bony crests extended much farther due to a keratin sheath. *T. navigans* bears a sharp, sail-like dome that rises high above the remaining skull. Some *Tupandactylus* preserve a keratinous beak on the jaw tips, which restricts to the crested area of the mandible. One specimen shows pycnofibers covering the jaw, extending far back. Preserved melanosomes suggest bright colours were present in the integument.

## Paleobiology

Sankar Chatterjee, Rick Lind, Andy Gedeon and Brian Roberts built a drone model led after *Tapejara* to test flight. They found the crest functioned like a sensory organ similar to a flight computer and aided in turning agility:

—Chatterjee
However, this has been questioned, since the wings were too long, with their actual wings capable of the soaring seen in galliformes. No aerodynamic function for the crest have been observed, but Chatterjee ignores recent aerodynamic studies.

*T. navigans* may have been a largely terrestrial forager. GP/2E 9266 indicates it was an able flyer, but likely spent much time grounded due to its large head gear, forelimbs and neck. It likely took short flights to escape predators. However, it was not adapted to terrestrial stalking like azhdarchids are. It was likely frugivorous.

## Classification

*T. navigans* and *T. imperator* were originally named as species of *Tapejara*, then moved to two new genera: *Ingridia* and *Tupandactylus*. Since *imperator* is considered the type, *Tupandactylus* takes priority, and *Ingridia* is found to be a junior objective synonym. Brain Andres et al. (2014) find:

In 2021 it was found:

## References

* https://en.wikipedia.org/wiki/Tupandactylus
* https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0254789
* https://www.scientificamerican.com/article/pterosaurs-may-have-had-brightly-colored-feathers-exquisite-fossil-reveals/?amp;text=Pterosaurs