Paleontologists have identified the Azdaltid wing bones, which belong to two newly discovered species of fossils from the Biansily Formation dating back to the Late Cretaceous period in the Gobi Desert of Mongolia.
Restoration of Bayanshiree Azhdarchid Pterosaurs: The coexistence of Gobiazhdarcho tsogtbaatari and tsogtopteryx mongoliensis in the Bayanshiree Paleoenvironment, with groups of Gobihadros Mongoliensis nearby. Image credit: Zhao Chuang.
These two new species thrived in Mongolia during the late Cretaceous period, approximately 99 to 90 million years ago.
They have been named Gobiazhdarcho tsogtbaatari and tsogtopteryx mongoliensis. Both flying reptiles are part of a toothless cosmopolitan family, likely associated with the terrestrial Azhdarchidae.
“Pterosaurs, the first vertebrates to develop powered flight, exhibit remarkable diversity, with a fossil record spanning from the late Triassic through the Cretaceous and into the Paleogene boundary.”
“Within pterosaurs, the Azdalcidae family signifies a distinct clade, currently accounting for at least 17 nominal species.”
“Primarily characterized by elongated cervical vertebrae with trace nerve spines, Azdaltids are commonly found in collections of Tronian Maaschan’s pterosaur fossils globally, representing the most diverse and widespread group during the late Cretaceous.”
“Similar to other Azdalcoids, they possess robust jaws and seem to have led a more terrestrial lifestyle compared to other pterosaurs.”
“Notably, Azhdarchids are recognized for including some of the largest flying creatures, such as Quetzalcoatlus northropi, Arambourgiania philadelphiae, and hatzegopteryx tambema, alongside the 9-meter wingspan Thanatos dracon amali.
The type specimens, Gobiazhdarcho tsogtbaatari and tsogtopteryx mongoliensis, were collected in the 1990s from two distinct locations within the Biansili Formation in the eastern Gobi Desert of Mongolia.
“Bayanshiree azhdarchids consist of two specimens: the Bayshin Tsav Azhdarchid (tsogtopteryx mongoliensis), which features nearly complete vertebrae from the middle neck, and the Burkhant Azhdarchid (Gobiazhdarcho tsogtbaatari), which includes vertebrae from cervical III and part of the core cervical,” stated the paleontologists.
“These specimens were gathered in 1993 and 1995 from the Bayshin Tsav and Burkhant regions, respectively, through efforts by the Museum of Natural History and the Mongolian paleontological archaeological expedition during the same years.”
According to the research team, Gobiazhdarcho tsogtbaatari represents a medium-sized early member of the Quetzalcoatlus–Arambourgiania lineage, with a wingspan of approximately 3.0-3.5 meters.
tsogtopteryx mongoliensis is an early representative of Hatzegopteryx, appearing to be a smaller form with a wingspan of less than 2 meters.
“Interestingly, the specimen tsogtopteryx mongoliensis, at a mere 1.6 meters in wingspan, stands as one of the smallest known Azdaltid species found to date,” noted the researchers.
The discovery of these two new species addresses a significant temporal gap in the evolutionary history of Azdalkid pterosaurs.
“Our findings provide new insights into the diversity and phylogeny of Azdaltid pterosaurs,” the scientists remarked.
“They further highlight the coexistence of various sized azdaltide species within the same sedimentary deposits.”
A paper detailing these findings was published online this week in the journal PeerJ.
____
RV Pegas et al. 2025. Diversity of the Azdaltid pterosaur clade in the Baiansili Formation during the late Cretaceous period of the Gobi Desert, Mongolia. PeerJ 13:E19711; doi:10.7717/peerj.19711
Source: www.sci.news
