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Geosternbergia (Pteranodon sternbergi)

"Toothless wing"

Pteranodon sternbergi is an extinct species of the pteranodontid pterodactyloid pterosaur genus Pteranodon from the Late Cretaceous geological period of North America. P. sternbergi was among the largest pterosaurs, with a wingspan of up to 6 metres (20 ft) in males. It has been argued that P. sternbergi should be classified in a separate genus, Geosternbergia, but this has not been followed by most other researchers.

The first fossils of Pteranodon sternbergi were collected by American paleontologist George F. Sternberg in 1952 from the lower portion of the Niobrara Formation. The fossils of the animal looked similar to those of the species Pteranodon longiceps, but the crests were set upright and in a slightly different position. In 1958, Sternberg and paleontologist Myrl V. Walker published a study about this peculiar find. In 1966, American paleontologist John Christian Harksen assigned the specimens found as a new species of Pteranodon called P. sternbergi due to its distinct upright crest that set it apart from P. longiceps. Halsey W. Miller however, concluded a revision of the different species of Pteranodon in 1971, and created three different subgenera. One of which was Sternbergia, which consisted of the Pteranodon specimens with upright crests. P. sternbergi was assigned to this subgenus along with another species called P. walkeri, but Miller then found out that the name Sternbergia had been preoccupied, so he changed it into Geosternbergia instead. Paleontologists like S. Christopher Bennett consider P. sternbergi to be older than P. longiceps, and therefore the direct ancestor of that species.