VARIATIONS IN COLONIZATION AND SUCCESSION PATTERN OF DIPTERAN FLIES OF FORENSIC IMPORTANCE ON INDIAN MOLE-RAT CARCASSES IN URBAN AND SUBURBAN LOCALITIES OF KOLKATA, WEST BENGAL: IMPLICATIONS IN CORPSE RELOCATION STUDIES

Abstract

Necrophagous diptera form the first wave of arthropod colonization of carrion, facilitating microbial decomposition and helping maintain the balance of the ecosystem, thus are of considerable importance both from ecological and forensic entomological perspective. The present study indicates the difference in dipteran species composition and its succession patterns observed in colonising Indian mole-rat (Bandicota bengalensis) carcasses in two different localities, an urban and a suburban region of Kolkata and its adjoining areas in West Bengal during the month of April. It was observed that from the urban locality, a total of eight dipteran species belonging to three different families were recorded from the rat carrion, whereas, six dipteran species from four families were recorded from the suburban region. Moreover, in the urban habitat, it was noticed that the muscids were the predominant colonizers both with respect to species richness, abundance and frequency of colonization. The suburban area showed overall uniformity in terms of species richness and abundance in all the families. The two carcasses were seen to differ in dipteran succession patterns as well, with muscids, Synthesiomyia nudiseta being the first and Atherigona orientalis, the last to colonize in the urban region, in contrast to the suburban region with Chrysomya rufifacies (Calliphoridae), the first and Megaselia scalaris (Phoridae), the last species to colonize the carcass. Synthesiomyia nudiseta and Chrysomya rufifacies were the most abundant species found in the urban and suburban areas respectively.  The study, first of its kind in India, will aid in future studies on carrion ecology and forensic entomological research of this region.