The morphometric variation among 138 water frogs collected in Turkey at twelve localities extending from the Mediterranean coast in the south to the Black Sea coast was analysed using principal component and discriminant analyses. The water frog sample was heterogeneous and included two diagnosable morphs. Comparison with specimens from the type localities of Rana bedriagae (Damascus, Syria) and R. ridibunda (Atyrau, Kazakhstan) demonstrated that the most common water frog taxon in Turkey is R. bedriagae. The second morph was restricted to Ulubey, near Ordu, and was not conspecific with either R. bedriagae or R. ridibunda. It was, however, morphometrically closer to R. bedriagae than to R. ridibunda. As we were unable to locate an extant population of frogs which resembled the preserved sample from Ulubey, the taxonomic status of these morphometrically distinct water frogs remains unresolved. The large water frogs of the Anatolian Lakes District were indistinguishable from R. bedriagae in size-adjusted shape, but their maximum size exceeded that of R. bedriagae from all other localities by about 30 mm. We therefore provisionally refer to them as R. bedriagae caralitana. Reliable taxonomic recommendations require further information on independent character complexes such as advertisement calls and allozymes.