Hamipterus

In 2006 from the Hami region in Xinjiang, the Shengjinkou Formation, a Konservat-Lagerstätte was reported, in this case lake sediments allowing for an exceptional preservation of fossils. The same year, Qiu Zhanxiang and Wang Banyue started official excavations. Part of the finds consisted of dense concentrations of pterosaur bones, associated with soft tissues and eggs. The site represented a nesting colony that storm floods had covered with mud. Dozens of individuals could be secured from a total that in 2014 was estimated to run into the many hundreds. In 2014, the type species Hamipterus tianshanensis was named and described by Wang Xiaolin, Alexander Kellner, Jiang Shunxing, Wang Qiang, Ma Yingxia, Yahefujiang Paidoula, Cheng Xin, Taissa Rodrigues, Meng Xi, Zhang Jialiang, Li Ning, and Zhou Zhonghe. The generic name combines that of the Hami region with a Latinised Greek πτερόν, pteron, "wing". The specific name refers to the provenance from the Tian Shan, a mountain range. The holotype, IVPP V18931.1, has been found in a layer of the Tugulu Group dating from the Lower Cretaceous. It consists of a skull, probably of a female. The paratype is IVPP V18935.1, the skull of a male individual. The inventory number IVPP V18931 does not pertain to a single skeleton, but to a block containing various bones of different individuals. Eleven such blocks had in 2014 been secured, numbered IVPP V18931 to V18941. Together, they comprise the remains of at least 40 animals, both bones and soft tissue remnants such as the horn sheaths of skull crests. Exceptionally for pterosaur fossils, the bones have not been crushed, but were preserved three-dimensionally in good condition. Five uncrushed eggs were also found. The finds in 2014 represented the largest known concentration of pterosaur fossils, with the exception of the Pterodaustro nesting colonies of Argentina. ==Description==

The wingspan of the individuals described in 2014 ranged from . Hamipterus possessed a synostosis joint formed by the coracoid and scapula, with residual calcified portions of the articular cartilage being preserved from the scapular fossa where the joint was located. == Phylogeny ==

compared with that of Hamipterus'' Hamipterus was within the Pterodactyloidea, placed into the group Pteranodontoidea. An exact cladistic analysis could not resolve the relationship with Istiodactylus, Ludodactylus and the Anhangueridae. }} }} }} }} }} }} }} }} ==Paleobiology==

The large number of individuals found allowed the establishment of a growth series, showing how individuals developed through their ontogeny. Larger animals feature a number of changes. Their snout tips become relatively wider. The snout crest becomes more robust and expands its base towards the front, beginning at the level of the fifth tooth instead of the sixth. The pattern of grooves and ridges on the crest grows more prominent. The snout tip also starts to straighten in side view, no longer curving upwards. The groove in the dentary deepens and lengthens, as well. No change, however, takes place in the number of teeth, the degree of fusion in the symphysis of the lower jaws, or the shape of the postcranial skeleton, as far as can be ascertained, given the fact that the elements behind the skull were not found articulated. However, this study has since been criticized by some paleontologists. A 2021 further disagrees by demonstrating that the young of Hamipterus don't differ significantly from the other flight capable flaplings. == See also ==