Isozyme evidence for three sibling species in the Anopheles sundaicus complex from Indonesia

Electrophoretic studies of isoenzymes in three chromosomally distinct forms (A, B and C) of the mosquito Anopheles sundaicus Theobald (Diptera: Culici ae) were undertaken on wild samples collected from six geographically isola ted populations in Indonesia. Analyses of 12 enzyme systems comprising 15 l oci revealed significant allelic variations, genetic polymorphism, within a nd among the populations of the An. sundaicus complex. Phylogenetic dendrog rams produced by analysis using the Biosys-1 program based on UPGMA methods show that all the populations of form A fall into one cluster, which is cl osely related to the form C cluster, whereas the populations of form B belo ng to a more distinct cluster. Allelic frequency and Wright's F statistics of Mpi (mannose phosphate isomerase) are sufficient to identify individuals of each cytological form. This isozyme data correlates with our previous c ytological evidence for the existence of three isomorphic species within th e taxon An. sundaicus in Indonesia. These three species of the An. sundaicu s complex were found together sympatrically at one locality, Asahan in Nort h Sumatra.