Forensic Entomology: Arthropods collected on decomposing pig carrions in Warri, Delta State, Nigeria.

Abstract

A data base of arthropods of forensic importance was collected from pig carrions from 10th June to 10th August 2017 in the Warri city, 3 pigs were killed by cervical dislocation and left to decay while the daily assemblage of arthropods were collected from it. The result showed 5 stages of the carrion decomposition; fresh, bloated, active decay, advance decay and dry decay correspondingly despite that there was only a single sequence of decomposition. Entomofauna groups from 3 orders of Diptera, Coleoptera and Hymenoptera, with ten families were collected during the study while 233 insects were collected at the fresh stage, 324 were collected at the bloat stage, and 328 were recorded at the active decay stage, 405 at the advance decay stage and only 158 at the dry decay stage. The dominance index was high (0.09) at the dry decay stage but low (0.06) at the bloat, active decay and advanced decay stages. Shannon–Wiener index (H) was high (2.91) in the advanced decay stage but was low (2.52) at the dry decay stage. Arthropod from the orders of Diptera and Coleoptera were forensically significant as they used the carcasses for feeding and oviposition and could be used in the estimation of the post mortem interval while the order Hymenoptera used the carrion as extension of their habitat and as predatory ground to the necrophagous groups, it is advocated that more studies be carried out in different seasons using different animal models to create dependable data base of forensically importance arthropods in Warri and its environs.