Aneuretus simoni emery occurrence and the ant community observed by multiple methods and repeated sampling in “Pompekelle”, Sri Lanka

Abstract

The ant community of “Pompekelle” is of special interest due to the presence of island-endemic Aneuretus simoni Emery among them. Frequency of occurrence and proportional abundance of A. simoni workers and, species richness and composition of ant community were investigated using several sampling methods simultaneously on six visits to the forest from February to November 2004. Day time sampling of ants was carried out along ten, 100 m transects by mini-Winkler extraction, soil sifting, pitfall trapping, honey and canned fish baiting, leaf litter sifting, timed hand collection and beating tray method. Honey baits at 1 m height on trees and honey-baited pitfall traps on the ground were also set overnight. Aneuretus simoni workers were detected on all occasions. Honey baiting and litter sifting in day time caught the workers more often than canned fish baits, soil sifting, day time pitfall traps and night pitfall traps. Detectability of A. simoni was irregular in the ten transects but the frequency of occurrence ranged from 30-80 percent and the species comprised 1-6 percent of workers collected on each of the six occasions. It was a permanent minor component in the forest despite its absence in the area of transect 8. Fifty species of 36 genera in 11 subfamilies including the resident species, A. simoni, Anochetus sp., Anoplolepis gracilipes, Camponotus sp., Hypoponera sp. 2, Lophomyrmex quadrispinosus, Myrmicaria brunnea, Odontomachus simillimus, Pheidole sp. 7, Pheidologeton sp., Prenolepis sp., Solenopsis sp. and Technomyrmex albipes and other occasional ant species can be considered the first preliminary ant inventory of the forest.