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: Culiciae) were undertaken on wild samples collected from six geographically isolated populations in Indonesia. Analyses of 12 enzyme systems comprising 15 loci revealed significant allelic variations, genetic polymorphism, within and among the populations of the An. sundaicus complex. Phylogenetic dendrograms 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 closely related to the form C cluster, whereas the populations of form B belong 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 cytological evidence for the existence of three isomorphic species within the taxon An. sundaicus in Indonesia. These three species of the An. sundaicus complex were found together sympatrically at one locality, Asahan in North Sumatra.     

Disappearance of malaria vector Anopheles sundaicus from Chilika Lake area of Orissa State in India

Malaria has declined around Chilika Lake (85°20′ E, 19°40′ N) in Orissa State, India, from hyperendemicity in the 1930s to hypoendemicity during recent decades. Six decades ago, 21 spp. of Anopheles mosquitoes (Diptera: Culicidae) were recorded from this area, including the well known Indian malaria vectors An. culicifacies Giles, An. fluviatilis James, An. maculatus Theobald, An. stephensi Liston and An. sundaicus (Rodenwaldt), the last formerly regarded as the main vector locally. Surveys of Chilika area during 1995–96 found 8 spp. of culicine plus 14 spp. of anopheline mosquitoes, the latter comprising An. subpictus Grassi sensu lato, An. hyrcanus (Pallas) s.l., An. vagus Dönitz, An. annularis van der Wulp s.l., An. culicifacies Giles s.l., An. aconitus Dönitz, An. varuna Iyengar, An. barbirostris van der Wulp s.l., An. philippinensis Ludlow, An. ramsayi Covell, An. jeyporiensis James, An. pallidus Theobald, An. tessellatus Theobald and An. karwari James in decreasing order of abundance. Among indoor‐resting female mosquitoes, the anthropophilic index was 4–7% and some species (An. culicifacies, An. subpictus, An. vagus) tended to enter houses for resting after blood‐feeding outside. Females of potentially infective age (three‐parous) were obtained for An. culicifacies (11%) and An. annularis (< 2%), the more abundant established vector in this coastal area, but not for small samples of An. subpictus and An. vagus. Anophelines reported previously but not found in our survey were An. fluviatilis, An. jamesii Theobald, A. maculatus, An. splendidus Koidzumi, An. stephensi, An. theobaldi Giles and the former main vector An. sundaicus.