Santanadactylus (meaning "Santana Formation finger") was a genus of pterodactyloid pterosaur from the Albian-age Romualdo Member of the Upper Cretaceous Santana Formation, of Barra do Jardim, Araripe Plateau, Ceará State, Brazil. Four species have been named, but today are no considered congeneric with each other. It was a rather large pterosaur.
The genus was named in 1980 by the Dutch paleontologist Paul de Buisonjé. The type species is S. brasilensis, the specific name referring to Brazil. It is based on holotype UvA M 4894 (Geological Institute of the University of Amsterdam), an upper part of the right humerus and a right scapulacoracoid. UvA M 4895, consisting of two cervical vertebrae from a different individual, was assigned as a paratype, referred because it was found in the same lot of 25 chalk nodules bought from collectors. Additional remains, including a notarium (fused vertebrae supporting the shoulder) were subsequently referred to the taxon by Wellnhofer et al. (1983) and Wellnhofer (1991).
In 1985, Peter Wellnhofer, a German paleontologist who has written numerous scientific publications on pterosaurs, named three additional species: S. araripensis, S. pricei, and S. spixi. S. araripensis, named after the Araripe Plateau, was a large species based on BSP 1982 I 89, remains including a partial skull (missing the end of the jaws) and arms; the preserved skull section had no crest. S. pricei, named after Llewellyn Ivor Price, was the smallest of the three species; it was based on BSP 1980 I 122, a left wing from the elbow down, and additional arm material has been referred to it over the years. S. spixi, intermediate in size, was based on BSP 1980 I 121, another left wing, the name honoring Johann Baptist von Spix.
Over the years, the species of this taxon have been reassessed. Chris Bennett suggested that the hypodigm of S. brasilensis was a chimera of a pteranodontid and something else (in that the holotype and paratype belonged to different forms), S. araripensis and S. pricei were pteranodontids, and S.