Dugesia sagitta is a species of dugesiid triclad that inhabits the rivers of Corfu, Greece. The specimens of this species are up to 10 millimetres (0.39 in) long and 3 millimetres (0.12 in) wide. In 1925 Komarek synonymized Dugesia sagitta (then Planaria sagitta) with D. gonocephala, because the morphological description given by Schmidt when the species was named in 1861 was not accurated. In 1984 D. sagitta was back from the synonymization thanks to the contribution of a more accurated morphological description done by de Vries. In 1861 Schmidt also described D. sagitta from Cephalonia, but de Vries demonstrated that it was actually D. aenigma.