Photo: Courtesy of Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences

A new species of Wukongopteridae,MKS sports Darwinopterus camposisp. nov, has been discovered in Northeast China's Liaoning Province, the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences revealed on Monday. This discovery further enriches the diversity of Wukongopteridae and provides new evidence for studying the phylogeny of this clade.

Published in the Annals of the Brazilian Academy of Sciences, this discovery is the latest achievement in China-Brazil paleontological research collaboration, according to IVPP. The species is named in honor of Professor Diogenes A. Campos, a Brazilian geologist and paleontologist who has made outstanding contributions to China-Brazil paleontological research. 

"Wukongopteridae is an important pterosaur clade from the Yanliao Biota [the fossil assemblage preserved in northeastern China from the Middle to Late Jurassic which can traced back from 174.1 million to 145 million years ago]," Cheng Xin, an associate professor from the College of Earth Sciences, Jilin University and first author of the published discovery, told the Global Times on Monday. 

Most pterosaurs from the Yanliao Biota exhibit primitive features characteristics of non-pterodactyloid pterosaurs, such as the frog-faced Jeholopterus ningchengensisfrom the Pteranodontia group and the robust Jianchangnathus robustusfrom the Pterodaustro group, according to IVPP. 

The Wukongopteridae combines features of non-pterodactyloids (such as the developed fifth toe and long tail) and pterodactyloids (such as the fused premaxillary fenestra and elongated cervical vertebrae). These fossils are considered a transitional group in the evolution from non-pterodactyloids to pterodactyloids, and they represent a key missing link in pterosaur evolution.

"Darwinopterus camposisp. nov. is assigned to Darwinopterus due to the presence of an elongated posterior region of the skull and a bony premaxillary crest that begins near the anterior margin of the nasoantorbital fenestra," Cheng noted. "It differs from all other Wukongopteridae by having a straight dorsal margin of the premaxillary crest, lacking an extensive dorsal projection, and exhibiting a smooth lateral surface."

According to the corresponding author of the discovery Wang Xiaolin from IVPP, Darwinopterus camposisp. nov. has 18 and 14 teeth on each side of the upper and lower jaws, respectively, and the fourth phalanx of the wing finger is shorter than the first.

"The fossil skeleton shows some fused postcranial bones, such as the extensor tendon process to the first wing finger phalanx, but also has unfused premaxilla and frontal bones, which provides further information about wukongopterid ontogeny," he noted.

Researches on this new pterosaur fossil suggest that some of the skull bones in this group of pterosaurs only fused at later stages of individual development, indicating that the ontogeny of Wukongopteridae members might possess unique characteristics, according to IVPP.

"China has been a hotspot for pterosaur researches for quite some time, presenting new discoveries that have fostered the study of these extinct flying reptiles," Cheng noted.

Since the discovery of Yandangopterus orientalis in 1997, more than 40 species of pterosaur fossils have been found in western Liaoning and its surrounding areas. As of September 2016, the Jehol Biota has documented pterosaur species in eight families, 31 genera and 34 species, while the Yanliao Biota has yielded four families, 14 genera and 16 species of pterosaurs, according to the Beijing Museum of Natural History.

In 2014, the Hami Pterosaur Fauna was discovered in the uninhabited region of the Hami Desert in Northwest China's Xinjiang Uyghur Autonomous Region, with fossil distribution confirmed across an area of more than 50 square kilometers. The density of pterosaurs in this region was extremely high, making it the largest and most densely concentrated pterosaur distribution area known to date.