Descrizione di una nuova razza morfologica diDugesia (Schmidtea) polychroa (Turbellaria, Tricladida)della Sardegna

A planarian of theDugesia lugubris-polychroagroup, characterized by triangular head, is reported from Sardinia. The apical position of the eyes is similar to the one found inDugesia (Schmidtea) polychroa. The chromosome set, even if with slight differences, is related to the aforesaid species. Histologieal examination demonstrated its copulatory system to be different, in any detail, from those of the three species oflugubris polychroagroup. The Authors believe that, on the basis of the peeuliarity of both the morphological characters and the chromosome set, the above planarian is to be temporarily considered as a new race of theDugesia (Schimidtea) polychroaspecies. The denomination they suggest isDugesia (Schmidtea) polychroa macroauriculata.