Species diversity of Fireflies (Coleoptera: Lampyridae) in selected natural and agricultural habitats in Southern Sri Lanka

Abstract

Sampling of fireflies in five selected habitats representing in Hambantota, Matara and Galle Districts of Southern Province was conducted during October 2006 to February 2008. Samplings were carried out in two natural habitats; a mangrove forest and a natural forest and three agricultural habitats i.e. vegetable/ paddy cultivation, coconut and tea plantations in each district. Transect sampling was done using sweep nets. Collections of fireflies were carried out on three sampling occasions from 6.30 p.m. to 9.30 p.m. within the study period. Data on eight species of fireflies were analyzed by Shannon's Diversity index. Eight firefly species namely, Luciola chinensis, L. melaspis, L. humeralis, L.cingulata, Dioptoma greeni, D. ademsi, Diopenus latesence and Honasca necrobiodes were identified. The present study revealed that L. chinensis was the dominant lampyrid species in all habitats of three districts in Southern Province. Four species, L. cingulata, D. ademsi, D. latesence and H. necrobiodes were the least abundant. L. chinensis showed higher abundance compared to the other firefly species, it was well marked in all three agro ecosystems; Matara (65%), Galle (58%) and Hambantota (53%). However in natural ecosystems in all the three districts their percentage abundance was less than 40%. In contrast, L. melaspis was mainly restricted to tea plantations of three districts. Mean values of Shannon's Diversity index showed the highest species diversity in natural habitats of Galle District. Results also indicated that natural habitats had higher species diversity than the agro ecosystems in all three districts. Three unidentified Luciolinae species indicated that the possibility of new species in Sri Lankan firefly fauna.