Background: Sand flies belong to the subfamily Phlebotominae which is one of the six Psychodidae subfamilies with more than 800 species described worldwide, of which 98 species are confirmed and suspected Zoonotic cutaneous leishmaniasis (ZCL) due to Leishmania major is endemic in rural areas of 19 out of 31 provinces of Iran. Approximately 80% of reported leishmaniasis cases in the country are ZCL form. Phlebotomus papatasi is the main vector of ZCL to human in Iran. Phlebotomus (Paraphlebotomus) caucasicus (Ph. caucasicus) group belongs to the subgenus Paraphlebotomus, which has been considered as a complex species including Ph. caucasicus, Phlebotomus mongoloensis (Ph. mongolensis) and Phlebotomus andrejevi, playing a main role in maintenance of enzootic cycle of L. major among rodent reservoir hosts. Ph. caucasicus and Ph. mongolensis not only participate in the transmission cycle of ZCL among reservoir hosts but also play an important role as secondary vectors in the transmission of leishmaniasis to humans.Objectives: Delineate reliable morphological characteristics for the identification and separation of female
Phlebotomus caucasicus and Phlebotomus mongolensis, which are sympatrically present in the main foci of zoonotic cutaneous leishmaniasis in Iran.Materials and Methods: Sand flies were collected using sticky trap papers from active colonies of rodent burrows installed from 16 catching sites. Morphometric measurements were analyzed of 87
Phlebotomus caucasicus and 156 Phlebotomus mongolensis. Univariate and multivariate analysis were carried out to determine significant morphometric variables for discrimination of the two species. Finally, seven morphological characteristics of 65 female
Phlebotomus caucasicus and 124 female
Phlebotomus mongolensis were described.Results: Univariate and multivariate analyses of 10 morphometric variables via Discriminant Function Analysis (DFA) and Principal Component Analysis (PCA) showed that five morphometric variables had an accuracy of 100% for discriminating female
Phlebotomus caucasicus and Phlebotomus mongolensis. Moreover, PCA revealed that the five morphometric variables with the highest loadings separated these two species. Morphological studies on antennal flagellum (and its associated structures) and mouth-parts of female specimens demonstrated significant differences in several structures.Conclusion: The results show that morphological and morphometrical features can be used to discriminate two female isomorphic species,
Phlebotomus caucasicus and
Phlebotomus mongolensis accurately