Dietary and competition effects on life history attributes of Chrysomya megacephala and Lucilia sericata (Diptera: Calliphoridae) in south-west Europe.

The range of the oriental latrine fly (Chrysomya megacephala) is currently expanding. It coexists with another blowfly with a similar ecology, the green bottle fly (Lucilia sericata), one of the most abundant species in carrion during warm months. It is essential to understand the influence of temperature, larval substrate type, and larval competition on the development rates of these necrophagous calliphorids to evaluate the role and the adaptation of C. megacephala in the ecosystems, and on the necrophagous Diptera community. Moreover, due to the forensic importance of both species, biological data are need for forensic purposes in south-west Europe. This study represents the first on the biology of C. megacephala in Europe, and of L. sericata in Spain. We performed a field experiment in Alicante province (south-east Spain) to analyse the monthly abundance of both species in natural conditions, and three lab rearing experiments involving both species to evaluate (i) development at constant temperatures, (ii) the growth of larvae and pupae on different substrates, and (iii) coexistence in pure and mixed cultures under controlled abiotic conditions. The results allowed us to analyse the biological differences between both species, and their effects on the forensic entomology application.