On the Biology of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae)

Abstract

Blowflies belonging to the family Calliphoridae are of considerable medical and veterinary importance. The larval forms of these flies are found in human and animal body producing a pathogenic condition known as myiasis. Keeping in view the common availability of the C. megacephala Fab. and its economic importance, the present study has been undertaken to acquire the comprehensive knowledge about the biology and morphology of this pest. Various species of blowflies are used as forensic indicators during crime investigation in different parts of the world. Sufficient data is still not available about C. megacephala in India, so that they can be used in forensic investigations in our country as well. For accuracy in the estimation of the Post Mortem Interval (PMI), precise developmental data of the blowfly as a forensic indicator are essential. The morphological studies were made on laboratory reared flies. Flies were reared at two constant temperatures, 25°C and 30° C for studying their biology. The incubation period of eggs at 25°C and 30°C was found to be 19.16±0.3 hrs. and 11.9±0.14 hrs, respectively. It was observed that at higher temperature, larvae took less  to increased rate of metabolism at higher temperature. Total larval duration, pupal duration at 25°C were found to be 131.3±1.54 hrs and 126.25±1.88 hrs, respectively. These readings were decreased to 97.96± 0.47 hrs and 114.6±1.64 hrs with an increase in temperature to 30°C. Observations made on fecundity, hatchability, percentage pupation and percentage emergence at higher temperature shows an increase in comparison to lower temperature. While preoviposition and post-oviposition periods get decreased wi when the adult longevity is concerned, it has been observed that females live longer than males at both the temperatures.