Abstract
Sandflies are blood-sucking insects of great medical importance and are transmission vectors for several organisms that are infectious to humans. Three hundred fourteen adult sandflies were collected and morphologically identified as five species: Phlebotomus papatasi, P bergeroti, P sergenti, Sergentomyia antennata and S. clydei. P papatasi was the most abundant species (22.29%) of central region of Saudi Arabia, while S. clydei was the most abundant species (18.79 %) of southwestern region. Molecular_ classification of sandflies was done based on ribosomal RNA (rRNA) gene Internal Transcribed Spacer 2 (ITS2) sequences. ITS2 region was amplified using specific primers designed from a conserved region. Several clones from each individual were sequenced and analyzed using different DNA sequence analysis software. The results showed moderate variations (0.06%) between clones of same P papatasi individual. However, P sergenti individuals were highly divergent (0.207%). A phylogenetic tree, based on neighborjoining analysis, showed that morphologically identical individuals of same species exhibited significant variations at the molecular level. Cloned P bergeroti sequences were highly related to P papa fasi sequences (0.05%). Further, S. antennata species sequences were similar to S. clydeispecies sequences. In conclusion, molecular typing of sand fly species from Saudi Arabia based on ITS2 region may aid in differentiating between species and, possibly, sub-species.