Species composition and diversity of Odonata fauna in Cauvery River of Mettur dam, Salem district, Tamil Nadu, India

Odonata diversity study was carried out from September 2020 to October 2022 in the Mettur Dam, Salem District. Among the total 40 different species, 27 species were in Anisoptera (dragonflies) and 13 species in Zygoptera (damselflies) under five families. Libellulidae was the largest family recorded (16 species), followed by Coenagrionidae (11), Aeshnidae (2), Lestidae (2) and Gomphidae (1). A migratory species, Pantala flavescens, was the most dominant in numbers throughout the year. Maximum number of individuals was found during September 2020 to September 2021. Odonata diversity was higher in the first season of 2021 than in next second season. Both dragonflies and damselflies mainly used wetlands of the dam ecosystem and agricultural fields rather than shrubland.