Genetic diversity among three field populations of Lutzomyia longipalpis in
Colombia was studied using isozyme analysis. Study sites were as much as
598 km apart and included populations separated by the eastern Cordillera
of the Andes. Genetic variability among populations, estimated by
heterozygosity, was within values typical for insects in general (8.1%).
Heterozygosity for field populations were compared with a laboratory colony
from Colombia (Melgar colony) and were only slightly lower. These results
suggest that establishment and long term maintenance of the Melgar colony
has had little effect on the level of isozyme variability it carries.
Genetic divergences between populations was evaluated using estimates of
genetic distance. Genetic divergence among the three field populations was
low (D=0.021), suggesting they represent local populations within a single
species. Genetic distance between field populations and the Melgar colony
was also low (D=0.016), suggesting that this colony population does not
depart significantly from natural populations. Finally, comparisons were
made between Colombian populations and colonies from Brazil and Costa Rica.
Genetic distance values were high between Colombian and both Brazil and
Costa Rica colony populations (D=0.199 and 0.098 respectively) providing
additional support for our earlier report that populations from the three
countries represent distinct species.
