Application of COI DNA barcode to identify phlebotomine sand flies (Diptera: Psychodidae) from Maranhão in leishmaniasis-endemic areas, Northeast Brazil.

Abstract

This study evaluated the effectiveness of DNA barcoding, based on the mitochondrial COI gene, in delimiting species of the subfamily Phlebotominae from Maranhão, in addition to generating new molecular information and detecting possible cryptic species. Fragments of the COI gene were sequenced and integrated into public GenBank data. The species was delimited by means of species delimitation algorithms based on genetic distance (ABGD and ASAP) and phylogenetic gene trees (PTP), making it possible to identify patterns of cryptic diversity. In total, 54 consensus sequences were obtained, representing 23 species. Among these, Lutzomyia gomezi (Nitzulescu, 1931) and Psathyromyia punctigeniculata (Floch & Abonnenc, 1941) represent the first COI barcode sequences for these species in Brazil. BLAST and BOLD analysis coincided with morphological identification in most cases. The species Lu. sherlocki (Martins, Silva & Falcão, 1971) showed the greatest intraspecific distance and split into 2 clusters/MOTUs, suggesting the presence of distinct COI lineages or cryptic diversity. Unique clusters merging individuals of morphologically recognized species were also observed, such as Evandromyia lenti (Mangabeira, 1938)/Ev. carmelinoi (Ryan, Fraiha, Lainson & Shaw, 1986) and Psychodopygus complexus (Mangabeira, 1941)/Ps. wellcomei Fraiha, Shaw & Lainson, 1971. In view of these results, the need for further investigations using other molecular markers is evident, in order to expand the taxonomic resolution of these groups. Still, DNA barcoding (COI) proved to be efficient in delimiting most species and detecting possible cryptic species, while substantially expanding the molecular reference database for sand flies from Maranhão.