Post-feeding activity of Lucilia sericata (Diptera: Calliphoridae) on common domestic indoor surfaces and its effect on development

Abstract

Developmental data of forensically important blowflies used by entomologists to estimate minimum post mortem interval (mPMI) are established under controlled laboratory conditions for various temperature ranges throughout the stages of egg, 1st-3rd instar, puparia, and adult fly emergence. However, environmental conditions may influence the patterns of development and behaviour of blowflies, potentially impacting on these established development rates. Previous studies investigating indoor colonisation have focused on the delay to oviposition, with behaviour during the post-feeding phase in this setting often overlooked. The environment in which third instar larvae disperse when searching for a pupariation site may vary drastically at both outdoor and indoor scenarios, influencing the activity and distance travelled during this phase and possibly affecting developmental rates. This study investigated the effect of eight common domestic indoor surfaces on dispersal time, distance travelled, and behaviour of post-feeding Lucilia sericata as well as any resulting variation in development. It was found that pupariation and puparia length within a pupariation medium of sawdust (often used in laboratory settings) produced comparable results with that of carpeted environments (those deemed to be 'enclosed'). Non-carpeted environments (those which were 'exposed') produced a delay to pupariation likely due to increased activity and energy expenditure in searching for pupariation sites which enabled burial. In addition, the observed speed of travel during dispersal was seen via time lapse photography to be greater within 'exposed' conditions. Larvae which dispersed upon burnt laminate flooring were observed to travel faster than in all other conditions and showed the only significant variation (P=0.04) in the day of emergence in comparison to the control condition of sawdust. This study has demonstrated that wandering phase activity is affected by the environmental surface which has potential implications for estimating both the distance travelled by dispersing larvae in indoor conditions and with further research, may be a consideration in mPMI calculations.

A PRELIMINARY EVALUATION ON BIVARIATE ALLOMETRY IN ACTIVE-FEEDING Chrysomya megacephala (FABRICIUS, 1794) (DIPTERA: CALLIPHORIDAE) LARVAE

“…In the case of the larval body as a growth indicator, it would certainly have a better advantage than the cephalopharyngeal skeleton as the size reduces during the post-feeding phase and dispersal which could also be useful for referencing PMI min values (Gomes et al, 2006;Arnott & Turner, 2008;Robinson et al, 2018).…”

Estimation of life expectancy and measurement of immature stages ofLucilia sericatafed on three kinds of diets

“…They should be prepared locally or regionally for different strains of flies in each area using suitable diets. Obviously, different diets can have different effects on the body size of immature stages of flies (18). Therefore, the plotting of standard diagrams should be carried out in standard conditions in the laboratory and the most suitable diet should be used for this purpose.…”