[1] In 1980 a fossil site was discovered near Yacimiento de Fuente Amarga on the western slopes of the Peña Isasa.

[1] The type species Prejanopterus curvirostra was named and described in 2010 by Carolina Fuentes Vidarte and Manuel Meijide Calvo.

The species represents the best preserved pterosaur known from Spain and the first named from the Early Cretaceous of that country.

[1] In a later phylogenetic study Pereda-Suberbiola et al. (2012) recovered Prejanopterus as a pterodactylid, more precisely positioned between the genus Pterodactylus and the group Ctenochasmatoidea.

[2] Witton (2013) saw the genus as a possible lonchodectid due to its unusual tooth socket morphology and long, low nature of the jaw.