Pterorhynchus
Encyclopedia
Pterorhynchus was 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 rhamphorhynchid
Rhamphorhynchidae
Rhamphorhynchidae is a group of early "rhamphorhynchoid" pterosaurs named after Rhamphorhynchus, that lived in the Late Jurassic. The family Rhamphorhynchidae was named in 1870 by Harry Govier Seeley.-Classification:...

 "rhamphorhynchoid" 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 Late Jurassic
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago , which is preserved in Upper Jurassic strata. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age...

-age Daohugou Formation of Inner Mongolia
Inner Mongolia
Inner Mongolia is an autonomous region of the People's Republic of China, located in the northern region of the country. Inner Mongolia shares an international border with the countries of Mongolia and the Russian Federation...

, China
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...

.

The genus was named in 2002 by Stephen Czerkas and Ji Qiang. 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...

 is Pterorhynchus wellnhoferi. The genus name is derived from Greek pteron, "wing" and rhynchos, "snout", in reference to the tall crest on the head. The specific name honours the German 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...

.

The genus is based on 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...

 CAGS02-IG-gausa-2/M 608 (earlier DM 608). It was found in Chifeng
Chifeng
Chifeng , also known as Ulanhad, is a prefecture-level city in southeastern Inner Mongolia, People's Republic of China. It borders Xilin Gol to the north and west, Tongliao to the northeast, Chaoyang prefecture of Liaoning province to the southeast, and Chengde prefecture of Hebei province to the...

 in the Daohugou Beds. According to Ji Pterorhynchus belongs to the Yanliao Biota from the Haifanggou Formation
Haifanggou Formation
The Haifanggou Formation is a fossil-bearing rock deposit located in northeastern China, near Daohugou village of Ningcheng County. The rocks consists of coarse conglomerates, sandstone, mudstone and thin coal layers. The formation dates from the Middle Jurassic.-Arthropods:-Flora:...

 of the Callovian
Callovian
In the geologic timescale, the Callovian is an age or stage in the Middle Jurassic, lasting between 164.7 ± 4.0 Ma and 161.2 ± 4.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian....

; Lü Junchang in 2007 ascribed it to the somewhat later Tiaojishan Formation
Tiaojishan Formation
The Tiaojishan Formation is a geological formation in Hebei and Liaoning, People's Republic of China, dating to the middle-late Jurassic period . It is known for its fossil plants, and is made up mainly of pyroclastic rock interspersed with basic volcanic and sedimentary rocks...

 of the same stage.

This type specimen consists of an articulated, nearly-complete skeleton with remains of the integument. These included the wing
Wing
A wing is an appendage with a surface that produces lift for flight or propulsion through the atmosphere, or through another gaseous or liquid fluid...

 membrane, hair
Hair
Hair is a filamentous biomaterial, that grows from follicles found in the dermis. Found exclusively in mammals, hair is one of the defining characteristics of the mammalian class....

-like structures, a long version of the vane found at the end of "rhamphorhynchoid" tail
Tail
The tail is the section at the rear end of an animal's body; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, reptiles, and birds...

s, and a head crest with both a low bony base and a large 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...

 extension; the latter feature is unusual in "rhamphorhynchoids" (i.e. basal pterosaurs), the fossils of which do not often show head crests. The front part of the extension continued the leading margin of the bone base, extending at quite a sharp angle; it finally curved back to the base of the skull in a rounded curve. The crest covered the posterior two thirds of the head, showed the presence of large oval scales and was reinforced by a dozen ridges running parallel to the rounded trailing edge. At the base a vertical pattern was visible, interpreted as corresponding to the original camouflage colour patterning. The describers ascribed a primarily aerodynamic function to the crest, which is reflected in the genus name. The hairs were described as stranded or plumaceous and seen as corresponding to Stage II in the evolution of feathers and as indicative that pterosaur hair and dinosaur feathers were homologous. The type individual had an elongated skull 11.8 cm (4.65 in) long, a long tail and a wingspan
Wingspan
The wingspan of an airplane or a bird, is the distance from one wingtip to the other wingtip. For example, the Boeing 777 has a wingspan of about ; and a Wandering Albatross caught in 1965 had a wingspan of , the official record for a living bird.The term wingspan, more technically extent, is...

 of about 85 cm (33.46 in).

The describers assigned Pterorhynchus to the Rhamphorhynchidae
Rhamphorhynchidae
Rhamphorhynchidae is a group of early "rhamphorhynchoid" pterosaurs named after Rhamphorhynchus, that lived in the Late Jurassic. The family Rhamphorhynchidae was named in 1870 by Harry Govier Seeley.-Classification:...

. David Unwin's recent book The Pterosaurs: From Deep Time regarded it as a Cretaceous genus, but this was based on old information. He also suggested that it was a scaphognathine, related to Scaphognathus
Scaphognathus
Scaphognathus was a pterosaur that lived around Germany during the Late Jurassic. It had a wingspan of about one meter.-Naming:The first known Scaphognathus specimen was described in 1831 by August Goldfuss who mistook the tailless specimen for a new Pterodactylus species: P. crassirostris. The...

.

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