A morphological and morphometrical study of the closely related taxa Phlebotomus (Paraphlebotomus) sergenti et P. (Paraphlebotomus) similis confirms their specific taxonomic status. Differential characters between these two species are discussed. Males differ by the aspect of the basal process of the coxite which is curved and narrow in the first species whereas straight and thick for the latter. The P. similis process is bigger and tuffer and its style is longer than those of P. sergenti. Females differ by the morphology of the armature of the pharynx and by the number of rings of the spermatheca. Distribution areas of these species are described. P. similis is a North-Eastern Mediterranean species (from Yugoslavia to western Turkey and Azerbaïdjan). P. sergenti is present from Canary Islands (Spain) to India. From these data, the settlement of Paraphlebotomus in the Mediterranean basin may have occurred during the Miocene age. From an Asiatic common ancestor, two migration routes are proposed. One, north of the Paratethys Sea, may be responsible for the isolation of P. similis. The other, south of the Paratethys and Tethys Seas, may have contributed to the individualisation of P. sergenti. The authors consider P. similis as a suspected vector of Leishmania tropica.