Balaenognathus maeuseri gen. et sp. nov.: comparative interpretive drawings of the skulls of suspension feeding ctenochasmatoid pterosaurs in dorsal aspect. Balaenognathus this paper; Pterodaustro based on Bonaparte (1978); Plateleorhynchus based on Howse and Milner (1995); Gnathosaurus based on specimen JME-SOS 4580; Ctenochasma based on (2007 Fig. 2F)