Studies on populations of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera : Psychodidae : Phlebotominae) in Brazil

Studies were performed on five Brazilian populations of Lutzomyia longipalp is: Salvaterra (PA), Sao Jose do Ribamar (MA), Caninde (CE), Natal (RN) and Gruta da Lapinha, Lagoa Santa (MG). No morphological differences were obse rved that could distinguish between these populations. Homogeneity tests sh owed that the allopatric populations display a certain heterogeneity; and t hat the sympatric populations, with different patterns of spots, are homoge neous. The Student-Newman-Keuls test, represented by Euler-Venn diagrams, s howed a disjunction between the populations from the north/northeast and th e one from Gruta da Lapinha. Genetic distances between the four populations (excluding the Caninde population) were within the range of intrapopulatio nal differences. The Gruta da Lapinha population displayed a heterozygotic deficiency that could be a consequence of high levels of inbreeding due to cryptic habits of living in a small cave. These results do not favor the hy pothesis of a L. longipalpis species complex in Brazil, and the species sho uld be considered high polymorphic.