Oviposition interval and gonotrophic concordance in S outheast Asian anophelines

Mosquito survival and oviposition interval are important disease vector’s determinants that may vary within species depending on the environment. The length of the oviposition interval may be estimated by the proportion of mosquito ovaries with sacs. Fourteen species of Anopheles were collected from four locations in Cambodia and 1965 specimens were dissected. Both the number and predominant species collected varied according to location and trapping method. Five species were collected in sufficient numbers to allow comparisons between locations Sac rates differed between species but not within species between locations. Anopheles minimus had a higher sac rate in weeks leading up to a full moon. The more preserved environments supported more diverse anopheline fauna than the degraded environments. Despite the fact that many of the species occurred at very low densities there was no evidence of gonotrophic dissociation in any of the species. The principal malaria vector, An. dirus, was only common in one location where it was collected in miniature light-traps. It is suggested that a nationwide survey using such traps may help in determining patterns of malaria transmission in Cambodia.