PMI determination by the use of sarcosaprophagous Diptera is a routine method in forensic entomology. When the flies are concealed into their puparia the estimation of time-lapse between the discovery of a corpse and the presumed time of death is often delayed . In fact to perceive the changes that occur during the metamorphosis through the hardly sclerotized puparium is almost impossible. So the forensic entomologist is forced to rear the puparia and wait the adult emergence in order to estimate the PMI. A modified NIR-light microscope is here presented as a diagnostic tool useful to date a living fly during development, although the specimen is concealed into its puparium. A proper analogue or digital camera records the image because the human eye is unable to perceive NIR light. This non-invasive method is based on the intrinsic feature of NIR light that is to pass throughout the insect cuticle showing the hidden insect morphology and preserving the insect vitality; in this way is possible to carry on the rearing of insects successfully. The study of intra puparium stage of development of a fly will enhance the PMI estimation practice.
NIR (Near Infra Red) microscopy: a tool to reveal a developing fly inside its puparium
PORCELLI, Francesco;
2008-01-01
Abstract
PMI determination by the use of sarcosaprophagous Diptera is a routine method in forensic entomology. When the flies are concealed into their puparia the estimation of time-lapse between the discovery of a corpse and the presumed time of death is often delayed . In fact to perceive the changes that occur during the metamorphosis through the hardly sclerotized puparium is almost impossible. So the forensic entomologist is forced to rear the puparia and wait the adult emergence in order to estimate the PMI. A modified NIR-light microscope is here presented as a diagnostic tool useful to date a living fly during development, although the specimen is concealed into its puparium. A proper analogue or digital camera records the image because the human eye is unable to perceive NIR light. This non-invasive method is based on the intrinsic feature of NIR light that is to pass throughout the insect cuticle showing the hidden insect morphology and preserving the insect vitality; in this way is possible to carry on the rearing of insects successfully. The study of intra puparium stage of development of a fly will enhance the PMI estimation practice.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
