Paleontologists have described two new species of Azhdarchid pterosaurs from fossils found in the formation of the Tardif Bayanshiree Cretaceous in the Gobi desert in Mongolia.
Restoration of the life of the Azhdarchides of Bayanshiree: coexistence between Gobiazhdarcho tsogtbaatari And Mongolian tsogtopteryx in the paleoenvironment of Bayanshiree, with a group of Mongolian gobihadros close. Image credit: Zhao Chuang.
The two new species lived in Mongolia at the end of the Cretaceous era, between 96 and 90 million years ago.
Appointed Gobiazhdarcho tsogtbaatari And Mongolian tsogtopteryxThe two flying reptiles belong to a cosmopolitan family of toothless pterosaurs, probably in land called Azhdarchidae.
“Pterosaurs, the first group of vertebrates to develop the electric flight, presents a fossil record which extends from the Trias greater than the border of Cretaceous-Paléogenic, and an impressive diversity,” said the paleontologist of the University Shihezi Xuanyu Zhou and his colleagues from the Museu De-Zologana Da Usp and the Hokkaido University Museum.
“In the pterosaurs, the Azhdarchidae represent a very particular clade. At present, it includes at least 17 nominal species. ”
“Characterized mainly by their cervical vertebrae lying with neural spines vestiges, the Azhdarchides are an almost omnipresent presence in the assemblies of pterosaurs of the Turonian Maastrichtian worldwide, being the most diverse and most widespread group of pterosaurs during the end of the Cretaceous.”
“Similar to other Azhdarchoids, they sported toothless jaws and seem to have been relatively land in lifestyle compared to other pterosaurs.”
“Azhdarchides are well known, in particular to include the biggest flying creatures of all time, including gigantic forms with Despans 10-11-MM-Wings such as Quetzalcoatlus northropi,, Arambourgiania philadelphiaeAnd Hatzegopteryx thambemaas well as the 9-M-wingspan Thanatosdrakon Amaru. “”
Type specimens of Gobiazhdarcho tsogtbaatari And Mongolian tsogtopteryx were collected in the 1990s in two different localities of the Bayanshiree formation (also spelled Bayan Shireh, Baynshire, Bayshiree or Baysheen Shireh), which is located in the eastern region of the Gobi desert, in Mongolia.
“Bayanshiree Azhdarchides include two specimens: the Bayshin Tsav Azhdarchid (Mongolian tsogtopteryx), represented by an almost complete service environment; and Azhdarchid Burkhant (Gobiazhdarcho tsogtbaatari), including an Atlantoaxis, a Cervical III and a partial mid-service, “said paleontologists.
“These specimens were collected by the Hayashibara Museum of Natural Mongolian Sciences Paleontological Paleontological Center Paleontological Expedition in 1993 and 1995, respectively, the Bayshin Tsav and Burkhant localities.”
According to the team, Gobiazhdarcho tsogtbaatari represents an early medium-sized member (3.0-3.5 m in wingspan) Quetzalcoatla–Arambourgiania line.
Mongolian tsogtopteryx is a first member of a Hatzegopteryx-The opening lines and, surprisingly, seems to represent a small form of less than 2 m in ainer.
“It is interesting to note that Mongolian tsogtopteryx Until now represents one of the smallest known Azhdarchid species, only behind the Hornby Azhdarchid of 1.6 m-wingspan, of the Campanian of Canada, “said the researchers.
The discovery of these two new species fills important temporal gaps in the evolutionary history of Azhdarchid pterosaurs.
“Our results have highlighted the diversity and phylogeny of the Azhdarchid pterosaurs,” said scientists.
“They also reinforce the recurring coexistence scheme between several Azhdarchid species of different size from the same deposit.”
An article on results was published online this week in the journal Peerj.
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RV Pêgas and al. 2025. Diversity of Azhdarchides pterosaurs in the formation of Bayanshiree, upper Cretaceous of the Gobi desert, Mongolia. Peerj 13: E19711; Two: 10.7717 / peerj. 19711
