The New World Screwworm fly (NWS),Cochliomyia hominivorax, is an important agent of traumatic myiasis in livestock throughout Neotropical regions. In this work the mitochondrial DNA (mtDNA) variation and the wing morphological variation were used to examine the genetic variability and population structure of C.hominivorax from different geographic regions from South America. PCR-RFLP was used to survey mtDNA variation in control region (A+T-rich) and Cytochrome Oxidase subunits I and II (COI/COII) from seven populations of NWS: four from Brazil, one from Venezuela and two from Uruguay. The analysis was performed using three restriction endonucleases and there were found 5 different haplotypes for C.hominivorax. The nucleotide divergence among populations was estimated and the relationship was established based on NJ clustering; there were found three different groups sugesting that there are population structure in this species. The analysis of wing morphological variation was performed with two populations of NWS, one from Brazil and one from Venezuela; the differences between sex and localities were estimated comparing wing-length, wing-width and the ratio wing-width/wing-length. The data showed that C.hominivorax has a strong sexual dimorphism in wing shape. The results obtained with genetic divergence and analysis of variance clustering the populations from Caraguatatuba-BR and Barquisimeto-VE. Further analysis with other populations from Brazil, Uruguay and Venezuela has been conducting to elucidate the NWS intraspecific genetic variability at the geographic level and for monitoring the expansion in the current distribution and into screwworm-free areas. Financial support: FAPESP, CNPq, IAEA.
Species 1: Diptera Calliphoridae Cochliomyia hominivorax (New World Screwworm Fly)
Keywords: mtDNA, wing
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