V. THENMOZHI AND R. SIELVARAJ PANDIAN
Abstract
A comparative study on the mosquito species available in three different areas with different ecological conditions has been made. The study sites are AlagarHills forest, Idayapatti, a rural village and Natham, an urban town, which are located in Dinc-ligul district, Tamil Nadu, South India. Human landing and larval collections were made during pre-cultivation period (July and August 2006). Mosquito species composition showed a spatial variation among the three selected sites. In Alagar Hills forest, a total of 17 mosquito species belong to 6 genera such as /Wes (8), Culex (4), Anopheles (2), Orthopodomyia (1) Toxorhynchites (1) and Tripteroides (1) were recorded. In Idayapatti village, a total of 15 species belong to 4 genera namely Culex (9), Aedes (3), Anopheles (2) and Armigeres (1) were recorded. In Natham town, only 5 species of mosquitoes belong to 4 genera were recorded which includes Culex (2), Aedes (1), Armigeres (1) and Anopheles (1). The species richness index (a) is very high (0.90) in Alagar Hills forest area and the index is low in the rural area (0.56) and urban area (0.45). The diversity of mosquito fauna has been different among these three selected sites, indicating the existence of variation in the spatial distribution pattern. The variation in the diversity and distribution are mainly associated with specific ecological condition of the selected sites. The dominant species was Aedes (stegomyia) novalbopictus Barraud in the Alagar Hills, whereas in rural and urban areas, which were away from the forest fringe, the dominant species was Culex (Culex) quinquefasciatus Say. The fauna list includes few species, which are considered to be having medical importance in the study areas.