The diversity and distribution of dragonflies and damselflies (Odonata) in University of Lagos, Akoka, Lagos, south-west Nigeria

Abstract

The presence of dragonflies and damselflies may be taken as an indication of good ecosystem quality. The greatest numbers of species are found at sites that offer a wide variety of microhabitats. A survey of Odonata fauna inhabiting the University of Lagos, Akoka Lagos, south-west Nigeria was carried out between July and December 2014, with a view of determining its diversity and distribution. Four study sites used were Distance Learning Institute (DLI), Lagoon, Faculty of Science, and High Rise Area. Data collected were subjected to inferential statistics and analysis of variance (ANOVA). Diversity indices were used to compare the odonate species in the study sites. Seven hundred and fifty (750) individuals representing 39 species in 22 genera and four families (Aeshnidae – 3%, Coenagrionidae – 13%, Libellulidae – 81% and Calopterygidae – 3%) were recorded. Orthetrum (18%) was the most dominant genus, followed by Ceriagrion (10%) while Palpopleura and Trithemis (8%) were the least dominant genera. The site with most diverse Odonata fauna (H’ = 2.70, E = 0.27), was High Rise Area while the least was the Lagoon Area (H’ = 1.97, E = 0.27). Odonata in High Rise Area were significantly lower (p>0.0128) than those in DLI and Science Area which were not significantly different from each other (0.00039 and 0.00368 respectively). The paucity of species with narrow range of adaptation at the university especially at Lagoon Area where they were expected to occur is an indication that the forested part of the campus is under considerable human disturbance. Urgent measures are needed to preserve the natural the natural habitats of these Odonata species.

Keywords: Diversity indices; Odonata; fauna; diversity; distribution; University of Lagos; Nigeria