Abstract:
Calliphorid flies are the first to attack corpse, lay eggs on the openings and
develops the evidence for medicolegal investigations. However, their use
has been limited due to lack of species-wise thermo-biological profiles. In
this investigation, duration of life stages of three Calliphorid fly species,
Chrysomya megacephala, Lucilia sericata and L. cuprina, were determined
in winter, summer and rainy seasons.
At first, Calliphorid flies were reared on the putrefied liver mixed with meat
in cages under laboratory conditions. Identification of the flies was
confirmed using taxonomic keys. Fly species were released separately in
cages and allowed to lay eggs on the fresh liver-meat mixture. When
maggots hatched, they were fed with the same mixture until the pre-pupal
stage. The fully developed maggots stop feeding and moved to dry soil
provided in the cages for pupation. The pupae were allowed to develop into
adults in the same cages. Durations of life stages, temperature and humidity
during the experimental period relating to three seasons were recorded.
The days required to complete the life cycle in summer, rainy and winter
seasons for C. megacephala, L. sericata and L. cuprina, were 10, 14, 16, 9,
13 and 14 and 9, 14, 15, respectively. One day was required for the
development of egg and Istinstar for all the species. A major difference was
observed in pupation period during the three seasons. Warmer climate
accelerated the rate of development. Temperature plays an important role in
the development of these fly species. Hence, thermo-biological profiles are
needed to be developed for different species of Calliphorid flies for accurate
PMI determination.
