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Fly eggs found in corpses can be used as entomological evidence in forensic investigation. This study aims to investigate the morphology of forensically important fly eggs. Eggs of Chrysomya rufifacies, Chrysomya megacephala, Chrysomya pinguis, Chrysomya nigripes, Hypopygiopsis tumrasvini, Lucilia cuprina, Lucilia porphyrina and Musca domestica were examined using 1% potassium permanganate solution for 1 min. Morphometric analysis revealed that the mean length of Hy. tumrasvini (1.63 mm) and C. pinguis (1.65 mm) eggs was the longest, followed by that of L. porphyrina (1.45 mm), C. rufifacies (1.34 mm). The egg length, width of median area and darkness staining of hatching pleats were distinctive features. Four categories of median area were proposed, based on width; (1) distinctly wide (Megaselia scalaris, Synthesiomyia nudiseta); (2) wide (C. nigripes, M. domestica); (3) slightly widening (Hy. tumrasvini, L. cuprina, L. porphyrina); and (4) narrow (C. rufifacies, C. albiceps, C. megacephala, C. pinguis). Four species were examined using SEM, i.e., C. megacephala, C. pinguis, Hy. tumrasvini and L. porphyrina. The eggs of C. megacephala demonstrated swollen hatching pleats. Inside, the hexagon of the chorion appeared as a sponging bumpy feature. The egg of C. pinguis was similar to C. megacephala, except for the sponging bumpy feature on the outer surface of the hatching pleats. Regarding Hy. tumrasvini and L. porphyrina, their island structure was apparent at the inner surface of the upright hatching pleats. The key for identifying these eggs together with other reported species in Thailand has been updated.

In forensic investigations, all immature stages of flies (egg, larvae, and puparium) can serve as entomological evidence at death scenes. These insects are primarily used to estimate the post mortem interval (PMI), but can also be involved in the analysis of toxic substances, determining manner of death, and in indicating relocation of a corpse in homicide cases. In this study, we present the morphology of the egg, larvae, and puparium of Hemipyrellia ligurriens, a blow fly species of forensic importance in Thailand. Examination was conducted using scanning electron microscopy (SEM). The egg stage was found to display a relatively wide plastron region (or median hatch line area) that spans almost the entire length of the egg. The median hatch line is oriented in an upright position. External chorionic sculpture of the egg is present in a hexagonal pattern whose reticular boundaries are slightly elevated. In the larval stages, the most prominent morphological changes were detected upon comparison of the first to the second instar; whereas, the differences between second and third instar larvae were less obvious outside of the increase in number of posterior spiracular slits. Most of the major differences involve body size and structure of the anterior and posterior spiracles. Each anterior spiracle in both the second and third instars projects five to seven papillae apically. Each posterior spiracular disc of a third instar exhibits a complete peritreme, three spiracular slits, and a prominent button that is ventromedially located. The puparium is coarctate and features a clustered bubble membrane comprised of approximately 57 mammillate structures positioned dorsolaterally on each side of the first abdominal segment in young puparia. This feature is replaced by short, tubular respiratory horns in aged puparia. This study provides more detailed exposure of important morphological features that can be used for accurate identification of immature stages of H. ligurriens. Information presented can aid in forensic investigations involving this fly species.

The larval morphology and developmental rate of Chrysomya megacephala (F.) and Chrysomya rufifacies (Macquart), the two most forensically important blowfly species in Thailand, are presented. Morphological comparison of the third instar of both species revealed different characteristics (e.g., body appearance, cephalopharyngeal skeleton, dorsal cuticular spines between the prothorax and mesothorax, and feature of the posterior spiracle), thereby, allowing correct identification. A data analysis was conducted in Chiang Mai province, Northern Thailand during 2000-2001 on the developmental rate of both flies under natural ambient temperature and a natural light-dark photoperiod. The results indicated that larvae of C. megacephala developed more rapidly in April, pupariation initiated at 84 h at temperatures averaging 31.4 degrees C, and the larvae grew slower in the rainy season and winter. Similarly, rapid development of C. rufifacies larvae appeared in the summer, with a pupariation period as short as 96 h in June (average temperature 27.4 degrees C). Analysis of the median body length of C. megacephala and C. rufifacies larvae in different seasons of the years 2000-2001 in Thailand revealed that both species developed rapidly in the summer; pupariation of C. rufifacies initiated at 144 h, while C. megacephala initiated pupariation at 156 h. This information is potentially useful for estimating the postmortem interval of a corpse in forensic investigations, where the corpse becomes infesting with these fly species.

Personal identification was the major task of forensic doctors in Thailand's Tsunami. Identification can be done by visual identification, circumstantial evidence and physical evidence. Among the physical evidences dental data is the most effective method of identification, followed by fingerprint and DNA. A disaster Identification team should be set up to handle the problems and plan for the future.