Jeholopterus

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iJeholopterus
Fossil range: Early Cretaceous

Skeletal diagram of Jeholopterus by David Peters.

Extinct (fossil)

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Sauropsida
Order:	Pterosauria
Suborder:	Rhamphorhynchoidea
Family:	Anurognathidae
Genus:	Jeholopterus Wang et al., 2002

Binomial name

Jeholopterus ninchengensis
Wang et al, 2002

Jeholopterus was a small anurognathid pterosaur from the Early Cretaceous, preserved with hair and skin impressions, and named after its place of discovery, Jehol in China.

The type species is Jeholopterus ninchengensis Wang, Zhou, Zhang & Xu 2002 (IVPP V 12705).

In Jeholopterus the premaxillae curve dorsally 90 degrees from the posterior jugal. They curve nearly 180 degrees from the quadrate, which leans anteriorly from the glenoid. The orbit leans anteriorly. Only the anterior maxilla tooth is large (22 per cent of the skull length). Other maxillary teeth have not been found. The dentary teeth are in contact with one another, are homodont and short, like the teeth on a pair of pliers. The ectopalatine and pterygoid are the largest among pterosaurs and buttress the maxillary fangs along with the laterally expanded vomers. A caudal series of 35 tiny vertebrae tipped with a dense radiation of pterohair is preserved. The scapulae attach posteriorly to the seventh dorsal vertebra. The subequal manual phalanges are capable of hyperextension and their claws are capable of hyperflexion. The puboischial plate is shallower than the depth of the acetabulum. The pes is the most robust of all pterosaurs. Metatarsal V extends more than halfway down the metatarsus. Pedal 5.1 extends to 4.5. A single cranial strand extends in a curl to the pelvis. The cervical and dorsal plumes have fringed tops. The tail strands appear to be denser than in other anurognathids and confined to the tip.

The rattlesnake-like fangs and mandible, along with the buttressed palate, surgically-sharp unguals, robust limbs and other characters suggested to Peters (2003) that Jeholopterus was a vampire 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. By manipulating downloaded images in the computer art program Photoshop, Peters claimed to have discovered a bizarre suite of soft-tissue remains, including a horse-like tail Peters speculates may have been used as a fly sweeper/distractor, as well as a long fly lure (similar to that of the anglerfish) protruding from the head, and a fin or series of fins along the back. Thus far, none of these features have been recognized by other researchers.

[edit] References

Wang, X., Zhou, Z., Zhang, F., and Xu, X. (2002). "A nearly completely articulated rhamphorhynchoid pterosaur with exceptionally well-preserved wing membranes and 'hairs' from Inner Mongolia, northeast China." Chinese Science Bulletin 47(3), 226 – 232.