Tupandactylus
Encyclopedia
Tupandactylus is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of tapejarid
Tapejaridae
Tapejaridae 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....

 pterodactyloid pterosaur
Pterosaur
Pterosaurs were flying reptiles of the clade or order Pterosauria. They existed from the late Triassic to the end of the Cretaceous Period . Pterosaurs are the earliest vertebrates known to have evolved powered flight...

 from the Early Cretaceous
Early Cretaceous
The Early Cretaceous or the Lower Cretaceous , is the earlier or lower of the two major divisions of the Cretaceous...

 Crato Formation
Crato Formation
The Crato Formation is a geologic formation of Early Cretaceous age in northeastern Brazil's Araripe Basin. It is an important Lagerstätte for palaeontologists. The strata were laid down mostly during the early Albian age, about 108 million years ago, in a shallow inland sea...

 of Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

. It is notable for its large cranial crest, composed partly of bone and partly of soft tissue. The Tupandactylus genus possibly contains two species, both bearing differently sized/shaped crests that may have been used to signal and display for other Tupandactylus, much as toucans use their bright bills to signal to one another. Tupandactylus crests consisted of a semicircular crest over the snout, and in the case of the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 T. imperator, a bony prong which extended back behind the head. A second species, T. navigans, lacked this prong, and had a much more vertical crest. Soft tissue impressions also show that the small bony crests were extended by a much larger structure made of a keratinous material. The complete crest of T. navigans rose in a sharp, sail-like "dome" high above the rest of the skull.

Description

Tupandactylus imperator is known from four nearly complete skulls. The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

 specimen is MCT 1622-R, a skull and partial lower jaw, found in the Crato Formation, dating to the boundary of the Aptian
Aptian
The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 112.0 ± 1.0 Ma , approximately...

-Albian
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...

 stages of the early Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 period, about 112 Ma ago. It was initially described as a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of Tapejara, but later research has indicated it warrants its own genus. The skull was toothless and had a prominent sagittal crest, only the base of which was bony: the front of the crest featured a tall bony rod extending up and back, and the rear of the crest had a long prong of bone projecting behind it. The bulk of the crest was made up of soft tissue similar to keratin
Keratin
Keratin refers to a family of fibrous structural proteins. Keratin is the key of structural material making up the outer layer of human skin. It is also the key structural component of hair and nails...

, supported by the two bony struts. An additional skull described in 2011, specimen CPCA 3590, preserved more of the lower jaw, showing that like Tapejara, T. imperator had a large, asymmetrical "keel"-like crest on the underside of the lower jaw tip.

Some Tupandactylus specimens preserve evidence of a keratinous beak at the jaw tips. However, this was restricted to the crested portion of the lower jaw, as one specimen also preserves pycnofibres (simple feather-like filaments) covering the jaws further back.

Classification

Beginning in 2006, several researchers, including Kellner and Campos (who named Tupandactylus), had found that the three species traditionally assigned to the genus Tapejara (T. wellnhofferi, T. imperator, and T. navigans) are in fact distinct both in anatomy and in their relationships to other tapejarid pterosaurs, and thus needed to be given new generic
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 names. However, just how the species should be split proved controversial. Kellner and Campos considered only T. imperator to warrant a new name, creating Tupandactylus. However, another study published in 2007 by Unwin and Martill found that T. navigans, previously assigned to Tapejara, was actually most closely related to T. imperator and belonged with it in a new genus separate from Tapejara. In 2007, at a symposium held in honor of renowned pterosaur researcher Peter Wellnhofer
Peter Wellnhofer
Peter Wellnhofer is a German paleontologist at the "Bayerische Staatssammlung fur Paläontologie" in Munich. He is best known for his work on the various fossil specimens of Archaeopteryx or "Urvogel", the first known bird...

, Unwin and Martill announced the new genus name Ingridia, in honor of Wellnhofer's late wife Ingrid. However, when they published this name in a 2007 volume, they assigned imperator as the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 of their new genus, rather than navigans, which they also included as a species of Ingridia. Furthermore, Unwin and Martill's paper was not published until several months after the similar paper by Kellner and Campos. Therefore, because both sets of authors used imperator as the type, Ingridia is considered a junior objective synonym of Tupandactylus. It was not until 2011 that T. navigans was formally reclassified in the genus Tupandactylus, in a subsequent study supporting the conclusions of Unwin and Martill in 2007.

In popular culture

Tupandactylus navigans (classified as Tapejara at the time) appeared in the 1999 BBC television series Walking with Dinosaurs
Walking with Dinosaurs
Walking with Dinosaurs is a six-part documentary television miniseries that was produced by BBC, narrated by Kenneth Branagh, and first aired in the United Kingdom, in 1999. The series was subsequently aired in North America on the Discovery Channel in 2000, with Branagh's voice replaced with that...

, depicted during a hypothetical breeding season in Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

. Interestingly, though the series was released in 1999, T. navigans was not formally described and named until 2003.
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