Diversity and distribution of odonates in Alagar hills of Southern India

Order odonata includes important aquatic insect groups such as dragonflies and damselflies. They help to assess the ecosystem health and serves as pollution indicators. Studies of Odonata were conducted inAlagar hills of South India state ofTamilnadu fromAugust 2018 to January 2019. Odonate species abundance was high in October to November (7 to 8 species) and their abundance was low in the January and December (6 species.) Among all months, the abundance of libellulid species was comparatively high. Shannon index values were between 1.6094-1.9792 and it shows that these sites had critical position and they might have sensitive habitat status. The results of Simpson index complement with the results of Shannon index. Higher air and water temperature was in August and causes less diversity of organisms. DO was low in January (1.65) and it directly influences the abundance. This study interpreted that diversity of Odonates was directly and indirectly influenced by climatic change and anthropogenic impacts.