Unwindia: a Brazilian pterosaur known from a toothed snout

Unwindia trigonus is represented by one fragment of a long, narrow upper jaw from northeastern Brazil. Its teeth and alveoli are real fossil evidence. The wings, body and behaviour in the cover illustration are inferred or artistic, because none of those parts was found with the type specimen.

Quick facts

A specimen without a recorded excavation layer

David Martill named Unwindia trigonus in 2011 from specimen SMNK PAL 6597, acquired from a fossil digger in Santana do Cariri. It was not excavated in a documented bed. Its limestone nodule resembles material from what was then called the Romualdo Member of the Santana Formation, now generally referred to as the Romualdo Formation. That is a geological inference, not a precise field location.

The Karlsruhe specimen consists of joined premaxillary and maxillary bones and part of the palate. Splitting its nodule exposed mainly the right side; the counterpart has been lost. Thin bone is fragile and preparation was incomplete at first description. The genus honours pterosaur researcher David Unwin, while the species name refers to the triangular cross section of the snout.

What the teeth actually show

The original description counted seven pairs of tooth sockets in front of the large nasoantorbital opening. Four simple, slightly compressed conical teeth survive on the right. The front tip is damaged, so the very first socket has a small margin of uncertainty. About 192 mm of snout length was measured to the opening; that is a skull measurement, not body length.

The relatively short tooth row differs from several other toothed pterosaurs. Martill compared the rostral outline with Lonchodectes and discussed contrasts with the Araripe pterosaur Cearadactylus. None of these comparisons establishes Unwindia's diet. There are no stomach contents, identified prey remains, body bones or wing elements.

An unresolved branch and an inferred setting

Martill originally placed the genus among ctenochasmatoids. In a 2025 review of Araripe pterosaurs, Felipe Pinheiro and colleagues considered the holotype distinct but poorly preserved and still partly embedded in rock. They advised caution about the ctenochasmatoid placement because the proposed diagnostic characters cannot all be checked clearly. No additional specimen was referred to Unwindia in that review.

An exact age cannot be attached to a fossil whose stratigraphic horizon was never observed. The 2011 paper favoured a late Albian age for the supposed Romualdo unit, while later geological usage and dating have been refined. The staged fossil illustration and the living-animal scene both communicate possibilities rather than documenting this animal's actual colour, wings, feeding or shoreline.

Reading the pictures

The jaw fossil is the basis for the narrow, sparsely toothed muzzle. The research-table picture is staged art, not a photograph of the Karlsruhe holotype. The perched animal includes anatomical details and a habitat that remain untested by the single preserved snout.