Jeholopterus
Encyclopedia
Jeholopterus was a small anurognathid
Anurognathid
The Anurognathidae were a group of small pterosaurs, with short tails or tailless, that lived in Europe and Asia during the Jurassic and early Cretaceous periods...

 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 Daohugou Beds
Daohugou Beds
The Daohugou Beds are a series of fossil-bearing rock deposits located in northeastern China, with the type locality around Daohugou village of Ningcheng County south of Chifeng, Inner Mongolia, but extending into southwest Liaoning. The rocks are grey, finely bedded, lacustrine, sandy mudstones...

 of northeastern China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 (of uncertain age, probably Middle
Middle Jurassic
The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176-161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger....

 or 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...

), between 168 and 152 million years ago), preserved with hair and skin remains.

Naming

The genus was named in 2002 by Wang Xiaolin, Zhou Zhonghe
Zhou Zhonghe
Zhou Zhonghe is a Chinese palaeontologist. He described the ancient bird Confuciusornis.Zhou studied at the University of Nanjing and then worked at the Institute of Vertebrate Palaeontology and Palaeoanthropology of the Chinese Academy of Sciences in Beijing.- External links :* - Chinese* - Chinese...

 and Xu Xing. 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...

, the only known, is Jeholopterus ninchengensis. The genus name is derived from its place of discovery, Jehol
Jehol
Jehol could mean either a province or a city:* Jehol Province, former province in northeastern China* Chengde, the capital of above provinceNamed after the province:* Jehol Biota* Jeholodens* Jeholopterus* Jeholornis* Jeholosaurus...

 in China, and a Latinised Greek pteron, "wing". The specific name refers to Nincheng County.

Description

The type species 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...

 IVPP V12705, a nearly complete specimen from the Daohugou beds of Ningcheng County in the Neimongol (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...

) Autonomous Region of China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

. The specimen is crushed into a slab and counterslab pair, so that parts of the specimen are preserved on one side of a split stone and some on the other. This includes exquisite preservation of carbonized skin fibers and, arguably, "hair" or "protofeathers." The fibers are preserved around the body of the specimen in a "halo." Wing tissue is preserved, though its extent is debatable, including the exact points of attachment to the legs (or if it attached to the legs at all). In 2009 Alexander Kellner
Alexander Kellner
Alexander Wilhelm Armin Kellner is a Liechtensteinian/Brazilian paleontologist, a leading expert in the field of the study of pterosaurs....

 published a study reporting the presence of three layers of fibres in the wing, allowing the animal to precisely adapt the wing profile.

As an anurognathid, Jeholopterus shows the skull form typical for this group, being wider than it was long (28 mm), with a very broad mouth. Most teeth are small and peg-like, but some are longer and recurved. The neck was short with seven er eight cervical vertebrae. Twelve or thirteen dorsal vertebrae are present and three sacrals. There are five pairs of belly ribs. The tail vertebrae have not been preserved. The describers argue that Jeholopterus had a short tail, a feature seen in other anurognathids but unusual for "rhamphorhynchoid" (i.e. basal) pterosaurs that typically have a long tail. Wang et al. cited the presence of a fringe of hair in the region of the tail to infer the presence of a short tail. However, a subsequent study by Dalla Vecchia argued that gleaning any information about the tail is impossible, given that the tail is "totally absent" in the fossil.

The wing bones are robust. The metacarpals are very short. A short pteroid, supporting a propatagium, is pointing towards the body. The hand claws are long and curved. The wings of Jeholopterus show evidence that they attached to the ankle, according to Wang et al.. They are relatively elongated with a wingspan of ninety centimetres.

The legs are short but robust. The toes bear well-developed curved claws, but these are not as long as the hand claws. The fifth toe is elongated, according to the authors supporting a membrane between the legs, the uropatagium.

Phylogeny

Jeholopterus was by the authors assigned to the Anurognathidae. In 2003 a cladistic analysis by Kellner found it to be a member, together with Dendrorhynchoides
Dendrorhynchoides
Dendrorhynchoides was a genus of anurognathid pterosaur from the Early Cretaceous Yixian Formation, near Beipiao, Chaoyang, Liaoning, China...

and Batrachognathus
Batrachognathus
Batrachognathus is an extinct genus of "rhamphorhynchoid" pterosaur from the Late Jurassic Karabastau Svita of the central Asian republic of Kazakhstan....

of an anurognathid clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 Asiaticognathidae. An analysis by Lü Junchang in 2006 resolved its position as being the sister taxon of Batrachognathus.

Lifestyle

Anurognathids are normally considered insectivores. Wang e.a. hypothesised that Jeholopterus, being the largest species known of the group, might also have been a piscivore
Piscivore
A piscivore is a carnivorous animal which eats primarily fish. Piscivory was the diet of early tetrapods , insectivory came next, then in time reptiles added herbivory....

, a fish-eater.

Alternative interpretations

Though he never examined the fossil himself, advertising artist David Peters has popularized his idiosyncratic opinions about Jeholopterus and other pterosaurs widely on the internet. In general he finds and illustrates hosts of ornamental features and even multiple embryos although no other researchers have ever confirmed his findings. By manipulating downloaded
Uploading and downloading
In computer networks, to download means to receive data to a local system from a remote system, or to initiate such a data transfer. Examples of a remote system from which a download might be performed include a webserver, FTP server, email server, or other similar systems...

 images of Jeholopterus in the computer art program Photoshop, David Peters (2003) reported that he discovered an unusual suite of soft-tissue remains, including a horse-like tail Peters speculated may have been used as a fly sweeper/distractor, as well as a long fly lure (similar to that of the anglerfish
Anglerfish
Anglerfishes are members of the teleost order Lophiiformes . They are bony fishes named for their characteristic mode of predation, wherein a fleshy growth from the fish's head acts as a lure; this is considered analogous to angling.Some anglerfishes are pelagic , while others are benthic...

) protruding from the head, and a fin or series of fins along the back. Peters also reported that he had found "rattlesnake
Rattlesnake
Rattlesnakes are a group of venomous snakes of the genera Crotalus and Sistrurus of the subfamily Crotalinae . There are 32 known species of rattlesnake, with between 65-70 subspecies, all native to the Americas, ranging from southern Alberta and southern British Columbia in Canada to Central...

-like fangs", and these, along with what he described as a rattle-snake-like mandible, buttressed palate, "surgically-sharp" unguals, robust limbs and other characters suggested that Jeholopterus was a vampire
Vampire
Vampires are mythological or folkloric beings who subsist by feeding on the life essence of living creatures, regardless of whether they are undead or a living person...

 pterosaur adapted to plunging fangs into tough hide, then rotating the skull forward locking the fangs beneath the hide to improve adhesion. The small teeth of the lower jaw would not have penetrated but squeezed the wound like a pliers. Prominent pterosaur researcher Chris Bennett
Chris Bennett
Chris Bennett may refer to:* Chris Bennett , Grammy-nominated singer, dancer and composer* Chris Bennett , former Canadian international and NASL soccer player...

has described Peters' findings as "fantasy" and has vehemently denounced his methodology.

External links

  • Discussion of the validity and uses of computer tracing techniques, from the Dinosaur Mailing List
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