Paleontologists have announced the discovery of a new species of quetzalcoatline azhdarchid pterosaur, Nipponopterus mifunensis, from the Late Cretaceous of Japan.
Life restoration of a group of giant azhdarchids, Quetzalcoatlus northropi, foraging on a Cretaceous fern prairie. Image credit: Mark Witton / Darren Naish.
Pterosaurs were highly successful flying reptiles (not dinosaurs, as they’re commonly mislabeled) that lived between 210 and 65 million years ago.
They were Earth’s first flying vertebrates, with birds and bats making their appearances much later.
Some pterosaurs, such as the giant azhdarchids, were the largest flying animals of all time, with wingspans exceeding 9 m (30 feet) and standing heights comparable to modern giraffes.
“Pterosaurs, the earliest vertebrate group to achieve powered flight, have left a fossil record spanning from the Late Triassic to the Cretaceous/Paleogene boundary, showcasing a remarkable morphological diversity,” said Mifune Dinosaur Museum’s Dr. Naoki Ikegami, São Paulo University’s Dr. Rodrigo Pêgas and their colleagues.
“The fragile nature of pterosaur skeletons, due to their pneumatic and thin-walled bones, renders their fossil record particularly patchy and skewed.”
“Most well-preserved and relatively complete remains are restricted to a few Lagerstätten around the world. In contrast, most other pterosaur-yielding deposits typically produce fragmentary specimens.”
“As an example of this, the Japanese pterosaur record is extremely scarce, so that every remain bears a particular significance.”
“The first pterosaur specimen found in Japan derives from the Yezo Group in Hokkaido and represents an indeterminate pteranodontid, comprising a partial femur, metatarsal, pedal phalanx, and caudal vertebra.”
A sixth cervical vertebra of Nipponopterus mifunensis. Image credit: Zhou et al., doi: 10.1016/j.cretres.2024.106046.
The newly-identified species was a member of Quetzalcoatlinae, a subfamily of the pterosaur family Azhdarchidae.
“Azhdarchids represent a very particular pterosaur clade, especially notorious for including the largest flying organisms ever, such as the 10-11-m- (33-36-foot) wingspan Quetzalcoatlus northropi, Arambourgiania philadelphiae, and Hatzegopteryx thambema,” the paleontologists said.
“The clade Azhdarchidae is most remarkably characterized by their elongated cervical vertebrae with reduced neural spines, and are found extensively across pterosaur communities from the Turonian to the Maastrichtian age worldwide.”
“They represent the most diverse and widespread group of pterosaurs during the Late Cretaceous.”
Named Nipponopterus mifunensis, the new species lived in what is now Japan around 90 million years ago (Late Cretaceous epoch).
“Nipponopterus mifunensis represents the first nominal species of pterosaur from Japan,” the researchers said.
“This new species shows numerous quetzalcoatline features, being strikingly similar to the unnamed Burkhant azhdarchid from the Turonian-Coniacian of Mongolia.”
A partial sixth cervical vertebra of Nipponopterus mifunensis came from outcrops of the Mifune Group near the Amagimi dam, Mifune town, Kumamoto prefecture, on the Japanese island of Kyushu.
“The specimen was found within the middle part of the Upper Formation of the Mifune Group, in a coarse lens-shaped sandstone bed, 30 cm (12 inches) in thickness and placed between two tuff layers,” the scientists said.
Their paper was published this month in the journal Cretaceous Research.
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Xuanyu Zhou et al. Reassessment of an azhdarchid pterosaur specimen from the Mifune Group, Upper Cretaceous of Japan. Cretaceous Research, published online November 16, 2024; doi: 10.1016/j.cretres.2024.106046
