Brasileodactylus

"Cearadactylus"

A pterosaur skull, MN 7019-V (formerly CB-PV-F-O93), was discovered in the Romualdo Formation of the Santana Group in the Araripe plateau of northeastern Brazil. It consists of a single skull and articulated lower jaw with a length of 57 centimeters (1.87 ft). It was traded to Italy in 1983 and bought by Guido Borgomanero for his collection. It was initially mentioned as the new ornithocheirid genus and species "Cearadactylus atrox" in a short abstract by Giuseppe Leonardi and Borgomanero. This did not count as a formal publication establishing the name by the rules of the International Code of Zoological Nomenclature. Two years later a proper scientific description was published by the same authors, properly coining the name. Several traits were said to distinguish it, notably the elongate front teeth, the lack of a crest on the snout, a larger rosette (expanded portion of the jaws) on the dentary than on the upper jaw, and a gap between the premaxilla and maxilla bones of the upper jaw. The name refers to the Brazilian state Ceará, and combines this with Greek daktylos, "finger", a reference to the wing finger of pterosaurs. The Latin atrox means "frightful", a reference to the fearsome dentition of the species. After Borgomanero's death, his wife donated the skull to the Brazilian Museu Nacional in Rio de Janeiro. In 1990, Cearadactylus appeared in the famous novel Jurassic Park.

The relationships of the apparently unusual genus remained engimatic following the original paper. Leonardi and Borgomanero considered its relationship to other pterosaurs uncertain, Peter Wellnhofer classified it its own family Cearadactylidae, David Unwin considered it a member of Ctenochasmatidae, while later authors would recognize it as an anhanguerid. In 2009 the specimen was properly prepared, revealing the end of the snout had been glued onto the specimen upside down. This meant that the end of the upper jaw had been interpreted as the lower, and vice versa. Resin paste had been used to exaggerate the size of the front teeth. It is likely these modifications were made by the original collectors, a common occurrence for poached fossils from the Sanatana Group. This corrected interpretation made it clear the original distinguishing traits were misinterpretations caused by the reconstruction. This discovery was first noted in a short 2010 publication by Bruno C. Vila Nova and followed by a complete redescription in 2014. This redescription revealed new traits such as a small crest and a bifurcating central groove on the lower jaw thought to distinguish the taxon from other anhanguerids. It was noted as very similar to Brasileodactylus, but tooth spacing and the bifurcation of the dentary groove were thought to distinguish them An additional Cearadactylus specimen, showing the same groove, was noted in a 2013 abstract.

In 2018, the Museu Nacional fire heavily damaged the original Cearadactylus specimen alongside those of other pterosaurs. Part of the specimen was recovered and multiple casts exist in institutions worldwide. In 2025 a study by Rubi V. Pegas and colleagues was published concluding that Cearadactylus was not a distinct genus but a synonym of Brasileodactylus. Re-examination of the holotype specimens of Brasileodactylus and Cearadactylus (prior to the 2018 fire). Tooth spacing was found to be highly similar between the specimens, and bifurcation of the dentary groove was not considered unpreserved rather than confidently absent in the holotype of Brasileodactylus. The holotype of Cearadactylus, however, was noted to possess additional grooves on either side of the bifurcated one, a trait thought to distinguish Brasileodactylus. Additional specimens likewise showed a combination of the bifurcated central groove and accessory grooves, and a unique pair of foramina on the lower jaw was observed in all specimens.

In 1993, Fabio Marco Dalla Vecchia named a second species, Cearadactylus ligabuei. The specific name honors Giancarlo Ligabue, the director of the Centro Studi Ricerche Ligabue in Venice. It is based on holotype CCSRL 12692/12713, again a heavily damaged crestless skull, 403 millimeters (15.9 in) long. The skull consists of two pieces, the front and the back part, glued together by fossil traders; it is uncertain whether they belong to the same individual or indeed to the same species. Dalla Vecchia was himself not convinced the new species in fact belonged to Cearadactylus, but the skull was not sufficiently unique to base its own genus on yet still too different from known species to be assigned to them, so he created a new species for the genus the fossil most resembled.^{[citation needed]} Subsequent authors have questioned a close relationship to "Cearadactylus", and the 2025 study concluded it requires a detailed reassessment.