Cryodrakon

The azhdarchid Cryodrakon boreas was named in 2019 by paleontologists David Hone, Michael Habib, and François Therrien. It’s known from a partial skeleton and some additional referred material found in the Upper Cretaceous Dinosaur Park Formation in Alberta, Canada. Its scientific name means “cold dragon of the north wind,” a reference to Alberta’s modern climate. 

The holotype specimen is represented by the fourth cervical vertebra, a rib, humerus, pteroid, wing metacarpal, a metatarsal, and a tibia. Other fossils referred to Cryodrakon includes additional cervical vertebrae, and material from the shoulder, ulna, wing metacarpals, wing finger phalanges, and femur. 

The cervical vertebrae are distinct, showing three pneumatopores on the front and back ends of the neural canal; one above the spinal cord, and two others alongside it. It’s further distinguished from other azhdarchids by the way the cervical vertebrae articulate with each other. On the rear end of each vertebra there is a large, heart-shaped extension of the vertebrae called the postexapophysis, that is well separated from the centrum. 

Cryodrakon, was among the largest pterosaurs, about the same size as Quetzalcoatlus, with a wingspan estimated to be about 10 m (33 feet). Like Quetzalcoatlus, it had an extraordinarily long neck, but was more robust and therefore heavier than its Texan kin. Nothing is known of the skull of Cryodrakon, but all other azhdarchids had very long, toothless skulls, superficially resembling living storks and herons. 

Azhdarchids have been interpreted as hunters of small terrestrial vertebrates like mammals, lizards, and small and baby dinosaurs. When Cryodrakon lived, from about 74 to 77 million years ago, this part of Alberta was a low, temperate to subtropical plain, covered by forests and crossed by numerous rivers, and an ideal hunting ground for large azhdarchids.