Distinction among the Puparia of Three Blowfly Species (Diptera: Calliphoridae) Frequently Found on Unburied Corpses
JA Amorim, OB Ribeiro+
Departamento de Parasitologia, Instituto de Biologia, Universidade Estadual de Campinas, Caixa Postal 6109, 13083-970 Campinas, SP, Brasil
An open access article from Mem. Inst. Oswaldo Cruz vol.96 no.6 Rio de Janeiro Aug. 2001. Vol. 96(6): 781-784, August 2001.
Calliphorid larvae are important in the decomposition of carrion. Since these larvae are present in the primary stages of succession on carcasses, they may be important indicators of death time and the movement of corpses in homicide investigations. In this study we examined the morphological differences among puparia of Chrysomya megacephala, C. putoria and Cochliomyiamacellaria. Puparia of the three species (N=30, each) were obtained from the F2 generation bred in culture medium at 25° C, and 60% relative humidity on a 12 h photoperiod. The interspecific differences found were related to the conspicuousness of six tubercles located in the region near the posterior spiracles and to the distance between the two peritrema involving the spiracles. The latter were (mean ± SD) 1.52 ± 0.31 mm for C. megacephala, 1.89 ± 0.28 mm for C. putoria and 1.65 ± 0.35 mm for C. macellaria. The results of the present study may be useful in forensic entomology.
Key words: Calliphoridae – carrion insects – decomposition – forensic entomology – puparia
The family Calliphoridae consists of carrion flies which may also feed on living tissues. These species are potentially dangerous to man and other animals since the larvae may cause myiasis and adults may transmit pathogens. The diseases transmitted by these flies cause substantial losses to the cattle industry (Norris 1959, Zumpt 1965, Greenberg 1971, 1973, Richard & Gerrish 1983). The genus Chrysomya was introduced in Brazil from Africa (Zumpt 1965) with the first records being from the states of Paraná (Imbiriba et al. 1977) and São Paulo (Guimarães et al. 1978). Chrysomya species are currently found from the southern United States to southern Brazil (Jiron 1979, Gagné 1981, Baumgartner & Greenberg 1984).
Insects are important in carcass decomposition, and calliphorids, which are among the most abundant and best studied carrion insects have been extensively used as indicators of the post mortem interval (death time) and of corpses translocation. These flies are therefore a valuable tool for forensic medicine (Megnin 1894, Smith 1986, Catts & Haskell 1990).
In this study, we show that it is possible to distinguish among three species (C. megacephala, C. putoria and Cochliomyia macellaria) based on characteristics of their pupae and puparia.