Diversity of mosquitoes and larval breeding preference based on physico-chemical parameters in Western Ghats, Tamilnadu, India

Abstract

ObjectiveTo study the diversity and distribution of mosquitoes in Western Ghats of Coimbatore and Nilgiris District, Tamilnadu, India. MethodsRandom collections were carried out during August-2013 to July-2014 in cesspits, animal footprints, rock holes, tree holes, drainages at study areas of Marudhamalai, Valparai, Mettupalayam in Coimbatore District and Dhottapeta, Coonoor, Gudalur in Nilgiris District of Tamilnadu, India by using suction tube and kerosene pump. Mosquitoes were identified by standard entomological procedures. ResultsA total of 1 018 mosquitoes (larvae and pupae) were collected from all over the study areas comprising 6 genera and 23 species. They are, Culex mimulus, Culex pseudovishnui, Culex quinquefasciatus, Culex vishnui, Culex khazani, Culex uniformis, Heizmannia chandi, Heizmannia grenii, Heizmannia indica, Oclerotatus anureostriatus, Oclerotatus albotaeniatis, Oclerotatus deccanus, Oclerotatus gubernatoris, Aedes aegypti, Aedes albopictus, Aedes edwardsi, Aedes krombeini, Toxorhynchites minimus, Toxorhynchites splendens, Anopheles aitkenii, Anopheles barbirostris, Anopheles culiciformis and Anopheles maculatus. Shannon-Weaver diversity index, Margalef's index of richness and Simpsons dominance index was also studied. From 6 sites, the highest mosquitoes were collected from Marudhamalai (309) and the least mosquitoes were collected in Mettupalayam (68). The study determined whether physicochemical characteristics differ between habitats with high and low presence of mosquito larvae. Based on Margalef's index of richness (Dmg), the highest values were present in Mettupalayam (5.214) study area and the lowest in Marudhamalai (3.837). It can be concluded from Shanon-Weaver index of diversity that, the highest values were present in Mettupalayam (2.947) and the least value were in Gudalur (2.410) during the study period. ConclusionsIn areas with reservoirs of disease, mosquito abundance information can help to identify the areas at higher risk of disease transmission. The study identifies mosquito species density and diversity of culicine and anopheline larvae. Hence, this research contribution has more significance for basic biological research and developing control strategies for vector borne diseases.