Composition and distribution of dragonflies and damselflies (Insecta: Odonata) in Iloyin Forest, Akure, Southwestern Nigeria

Abstract

Odonate fauna of Iloyin Forest was studied from October to December 2009 to have an overview of the species composition and distribution with the threat of deforestation in the area. Adult species were collected once a week using a sweep net throughout the period of the study from three study sites (denoted as I, II and III) with varying levels of anthropogenic disturbance. A total of 76 species belonging to eight families were recorded in the forest. The two most abundant families in the forest were the Libellulidae (Anisoptera) and Coenagrionidae (Zygoptera).  Palpolpeura portia, P. lucia and Congothemis dubia were the dominant species of Libellulidae, while Pseudagrion kersteni was the dominant coenagrionid.   Some species of Odonata usually associated with shaded forests were encountered in two of the study sites. The highest diversity and evenness indices were recorded at Site I, followed by Site II and the least recorded at Site III. Although shade-loving species recorded in the study area was an indication of its richness in forest Odonata, some may have however become locally endangered or extinct as a result of deforestation. A check in the rate of deforestation could preserve the few forest (endangered) species and restore the locally extinct ones that changed habitats.

 Key Words:     Biodiversity, Conservation, Disturbance, Forest, Freshwater, Odonata