The holotype CAMSM B54835, was described in 1870 by Harry Govier Seeley as the holotype of his species Ornithocheirus platystomus. In 1914 Reginald Walter Hooley moved O. platystomus to Amblydectes.[2] It was assigned by David Unwin in 2001 to the genus Lonchodectes,[3] and in 2013 was excluded from the Lonchodraconidae.[4] In a 2021 review of the genus Amblydectes, Borja Holgado considered platystomus a valid taxon and gave it its own genus, Draigwenia, reinterpreting it as an indeterminate member of Lanceodontia.
^Unwin D.M., (2001), "An overview of the pterosaur assemblage from the Cambridge Greensand (Cretaceous) of Eastern England", Mitteilungen aus dem Museum für Naturkunde in Berlin, Geowissenschaftliche Reihe 4: 189–221
