The long history and great ecological and morphological diversity of reptiles (all amniotes except mammals and birds) is matched by their visual system diversity. Although less known than in other amniotes, visual pigments have been studied in all extant reptile orders except Sphenodontia. There have been no additions to the five visual pigments present in the ancestral vertebrate, although there have been multiple independent losses. Crocodylians retain three visual pigments, many lizards as well as Testudines four or five and snakes one to three. Adaptive pigment evolution includes tuning site amino acid substitutions and switches between chromophore types that together generate ultraviolet to infrared spectral sensitivity. Reptiles present some of the best evidences of evolutionary rod–cone and cone–rod transmutation with, for example typically cone visual pigments expressed in rod-like photoreceptors. Reptile visual pigments show evidence of substantial adaptive evolution, at least some of which is associated with major ecological shifts.