Under a Giant’s Wing – Cryodrakon boreas

A new species of giant pterosaur has been named and described from fossil material excavated from the famous Dinosaur Provincial Park Formation in southern Alberta (Canada).  The flying reptile represents one of the geologically oldest azhdarchid pterosaurs described to date from North America.  It is the first flying reptile genus to be erected from Dinosaur Provincial Park fossils.  Writing in the academic publication, the “Journal of Vertebrate Paleontology”, researchers from Queen Mary University of London, the University of Southern California, and the Royal Tyrrell Museum of Palaeontology (Alberta), describe Cryodrakon boreas and estimate that it could have been one of the largest flying vertebrates to have ever lived.

A Life Reconstruction of the Newly Described Azhdarchid Pterosaur Cryodrakon boreas

Picture credit: David Maas

Giant Pterosaur from the Dinosaur Provincial Park Formation

Despite the discovery of many thousands of dinosaur bones from the Dinosaur Provincial Park (DPP), the fossilised remains of pterosaurs are exceptionally rare.  Their delicate, pneumatised bones do not do well when it comes to the fossilisation process.  What fossils that have been found, since the first discoveries made in 1972, are highly fragmentary and difficult to assign down to the genus level.  Individual cervical vertebrae, metacarpals and metatarsal bones have been described as representing azhdarchid pterosaurs as they bore resemblance to Montanazhdarcho, a pterosaur known from contemporaneous strata some 150 miles or so, south of the DPP, or indeed to the Quetzalcoatlus genus known from the Javelina Formation of Texas.

In this scientific paper, the researchers examined undocumented pterosaur fossil material and reassessed previously studied fossils and concluded that the remains, bones from the wing, limb bones, cervical vertebrae and a rib originally assigned to Quetzalcoatlus were sufficient different to merit the establishment of a new azhdarchid pterosaur genus.

A Line Drawing of an Azhdarchid Pterosaur Neck Bone from the Dinosaur Provincial Park Formation

Picture credit: Everything Dinosaur/Indiana University Press

“Cold Dragon”

The genus name is from the Greek and means “cold dragon”, reflecting the relatively high latitude where the fossils were found, commenting on why the fossils have been ascribed to a new genus, lead author Dr David Hone (Queen Mary University, London) stated:

“This is a cool discovery, we knew this animal was here but now we can show it is different to other azhdarchids and so it gets a name.”

Line Drawings of a Juvenile Azhdarchid Pterosaur Cervical Vertebra from the Dinosaur Provincial Park Formation

Picture credit: Everything Dinosaur/Indiana University Press

Giant Pterosaurs with a Wingspan of Five Metres

The associated fossil material represents a young animal, with an estimated wingspan of five metres, but one giant cervical vertebra from the DPP, once thought to represent a partial femur, indicates that mature adults were comparable in size to Quetzalcoatlus northropi.

The slightly more robust bones from the DPP (when compared to Javelina Formation material), suggests that Cryodrakon may have been slightly heavier than Quetzalcoatlus spp.  It is difficult to calculate bodyweights, but the press releases suggested an adult Cryodrakon might have weighed in excess of 250 kilograms.

Everything Dinosaur acknowledges the assistance of a media release from the Royal Tyrrell Museum, (Alberta) and a press release from Queen Mary University (London), in the compilation of this article.

The scientific paper: “Cryodrakon boreas, gen. et sp. nov., a Late Cretaceous Canadian azhdarchid pterosaur” by David W. E. Hone, Michael B. Habib and François Therrien published in the Journal of Vertebrate Paleontology.

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