Carrion-associated arthropods in rural and urban environments

Preferences of arthropods are important in forensic entomology, as the species collected can help determine the postmortem interval or if remains have been moved. This study looked at arthropods that are attracted to pig carcasses in rural and urban habitats in Northwest Indiana. The species and number of carrion-associated arthropods that are found at a carcass vary with habitat type, month, and stage of decomposition. Lucilia sericata (Diptera: Calliphoridae) is a synanthropic species that was found in higher numbers in urban locations for both adults and larvae. Though L. sericata had higher numbers in urban habitats, caution must be exercised when using the information in a criminal case, as adults and larvae were still collected in rural habitats, and thus presence of L. sericata does not conclusively show that remains were previously located in an urban habitat. No other Diptera or Coleoptera species showed a preference for habitat type. Isopoda were found in higher numbers in urban habitats. Calliphoridae species, except for L. sericata, had differences in numbers between the months studied (June-October). Most adult taxa and all larval taxa showed differences in numbers between decomposition stages. Succession tables for all arthropods and non-arthropods collected were created to show when taxa that were found at the carcasses. Crickets (Orthoptera: Gryllidae) were observed feeding on the carcass, and feeding holes left in the carcasses by dipteran larvae. The cricket feeding modified the appearance of the holes, which could be confused for antemortem or perimortem wounds in a criminal investigation