GENETIC-VARIABILITY AMONG POPULATIONS OF THE SAND FLY LUTZOMYIA (LUTZOMIYIA) LONGIPALPIS (DIPTERA, PSYCHODIDAE) FROM CENTRAL-AMERICA

Eleven Central American populations of Lutzomyia longipalpis (Lutz & N eiva) were analyzed for genetic variation at 16 enzyme loci. The aim w as to study the genetic structure among populations within this region and to identify demes that may represent different sibling species. G enotypic frequencies within populations agreed with Hardy-Weinberg exp ectations, indicating that there were no sympatric sibling species amo ng these 11 populations. Levels of genetic distance between pairs of p opulations were very low (<0.02). Some substructing was evident, becau se after genotypes of all populations mere pooled, 7 of the 16 enzyme loci deviated from Hardy-Weinberg expectations. Estimates of effective migration rates among populations (Nm) were low (3.7), indicating tha t gene now was restricted. These data explained observed genetic subst ructuring when all genotypes were pooled.