Effect of temperature on the life cycle of Euspilotus azureus (Coleoptera: Histeridae), a predator of forensic importance

Euspilotus azureus (Sahlberg, 1823) (Coleoptera: Histeridae) is one of the most frequently sampled species of Histeridae on carcasses in South America. Determining its physiological responses to different temperatures is essential for providing development rate equations to estimate the period of insect activity and postmortem interval of the body. Thus, to evaluate the influence of temperature on their life cycle and to understand their developmental threshold, experiments were conducted under laboratory conditions at 6 different temperatures (10, 15, 20, 25, 30, and 35 degrees C). All E. azureus life stages were responsive to thermal variations. Eggs of E. azureus did not hatch at extreme temperatures (10 and 35 degrees C) and the development time from egg to adult was longer at low temperatures (15 and 20 degrees C). Their biological responses, such as mean number of eggs produced, the number of eggs per egg mass, and development time at different temperatures, indicate that 20 to 25 degrees C is optimal for growth. The results suggest that E. azureus shows tolerance and adaptability in its ontogenetic stages over a wide temperature range, which is common in generalist species. Also, this study provides the development rate equation for the species, which is applicable to studies of forensic entomology.