Pteranodon and beyond: the history of giant pterosaurs from 1870 onward

The immense size of many pterosaurs is now well known to academics and laymen alike, but truly enormous forms with wingspans more than twice those of the largest modern birds were not discovered until 83 years after the first pterosaur fossils were found. These remains were discovered in an expedition to the Cretaceous chalk deposits of Kansas led by O.C. Marsh in 1870: initially revealing animals with 6.6m wingspans, Marsh eventually found material from animals estimated to span 7.6m. Marsh's record breaking pterosaur - the largest flying animal known for nearly 80 years - was equalled by a supposed wing bone described by C.A. Arambourg in 1954, and then surpassed with the discovery of the 10m span azhdarchid Quetzalcoatlus northropi by D. Lawson in 1972. Subsequent fragmentary azhdarchid discoveries suggest even larger forms: reinterpreting Arambourg's 'wing bone' as a cervical vertebra suggests an animal with a 11-13m wingspan, while the Romanian taxon Hatzegopteryx thambema ia a particulary large and robust form with a 12m wingspan. Giant pterosaur footprints are also known, with the largest footprints recording walking azhdarchids of comparable size to those suggested by body fossils.