CAMSM B54835, anterior portion of the rostrum (Fig. 12E–H).

Horningsea, Cambridgeshire, England.

Cambridge Greensand (Cenomanian; fossils Albian in age).

Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): alveoli small (about 4 to 5 mm in diameter); dorsal margin of the rostrum forms an angle of 27° with the ventral margin*.

‘Ornithocheirus’ platystomus is known from a partial premaxilla and maxillae. As Seeley (1870) pointed out, it is broken in its anterior tip, so that the first pair of alveoli is apparently not preserved. ‘Ornithocheirus’ platystomus can be excluded from Lonchodraconidae because it does not have raised alveolar rims and lacks a deep palatal ridge. The absence of these characters results in the lack of a parapet–like palate (which distinguishes Lonchodectidae sensu Unwin 2001). ‘Ornithocheirus’ platystomus presents a relatively tall rostrum, whose dorsal margin forms an angle with the ventral one; this angle lies between those in Ornithocheirus simus and Cimoliopterus cuvieri. The angle (about 27°) is so far unique among the species of the Ornithocheirus complex and confirms it as a valid taxon.