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Blow flies are worldwide the most important insects from a forensic point of view. In Thailand, aside from the two most common species, Chrysomya megacephala (F.) and Chrysomya rufifacies (Macquart), Chrysomya chani Kurahashi was also found to be of forensic importance. We present a case of a human female cadaver in its bloated stage of decomposition, discovered at Pachangnoi Subdistrict, northern Thailand. Entomological sampling during the autopsy displayed an assemblage of numerous dipteran larvae. Macroscopic observations showed the coexistence of third instar larvae of the three blow flies C. megacephala, Chrysomya villeneuvi Patton, an unknown blow fly species and one muscid, Hydrotaea sp. The minimum post-mortem interval was estimated to be six days, based on the developmental rate of C. megacephala. The ID of the unknown larva, which is the focus of this report, was revealed later as C. chani by DNA sequencing, using a 1205 bp of cytochrome c oxidase subunit I (COI). The occurrence of C. chani on a human body revealed the need to analyse and describe the morphology of its immature stage, to enable forensic entomologists to identify this fly species in future cases. The morphological examination of the third instar was performed, revealing peculiar characteristics: protuberant tubercles encircling abdominal segments; 9–11 lobes on the anterior spiracle; six prominent pairs of tubercles along the peripheral rim of the eighth abdominal segment; a heavily sclerotized complete peritreme of the posterior spiracles. A key to differentiate the third instar of blow flies of forensic importance in Thailand is provided.

Objective: To evaluate the results of the 2012 interlaboratory comparison for forensic deoxyribonucleic acid (DNA) typing including autosomal short tandem repeat loci (aSTR), Y-chromosome short tandem repeat loci (Y-STR), X-chromosome short tandem repeat loci (X-STR) and mitochondrial DNA (mtDNA). Material and Methods: The analysis was performed using 4 blood samples stored on FTA® cards. Twelve laboratories in Thailand participated in this study. The results from each participant were compared with the consensus results. Results: The analysis of aSTR, Y-STR, X-STR and mtDNA were performed in 12 (100.0%), 8 (66.7%), 6 (50.0%) and 7 (58.3%) laboratories, respectively. All DNA profiles of aSTR, Y-STR and X-STR from all the participating laboratories showed the same STR profiles. However, the calculation of forensic DNA typing statistical values and the format of laboratory reports among these laboratories showed several variations. Only the mtDNA test showed some variations among the laboratories. Conclusion: For aSTR, Y-STR and X-STR tests, the trainings in statistical calculation of forensic DNA typing are required. For mtDNA test, workshop training should be established. Furthermore, a standard guideline for forensic DNA typing reports should be released in order to provide all the necessary information in the laboratory reports.

Abstract  This paper presents and discusses 30 cases of cadavers that had been transferred for forensic entomology investigations to the Department of Forensic Medicine, Faculty of Medicine, Chiang Mai University, northern Thailand, from 2000 to 2006. Variable death scenes were determined, including forested area and suburban and urban outdoor and indoor environments. The fly specimens found in the corpses obtained were the most commonly of the blow fly of family Calliphoridae, and consisted of Chrysomya megacephala (F.), Chrysomya rufifacies (Macquart) Chrysomya villeneuvi Patton, Chrysomya nigripes Aubertin, Chrysomya bezziana Villeneuve, Chrysomya chani Kurahashi, Lucilia cuprina (Wiedemann), Hemipyrellia ligurriens (Wiedemann), and two unknown species. Flies of the family Muscidae [Hydrotaea spinigera Stein, Synthesiomyia nudiseta (Wulp)], Piophilidae [Piophila casei (L.)], Phoridae [Megaselia scalaris (Loew)], Sarcophagidae [Parasarcophaga ruficornis (F.) and three unknown species], and Stratiomyiidae (Sargus sp.) were also collected from these human remains. Larvae and adults of the beetle, Dermestes maculatus DeGeer (Coleoptera: Dermestidae), were also found in some cases. Chrysomya megacephala and C. rufifacies were the most common species found in the ecologically varied death scene habitats associated with both urban and forested areas, while C. nigripes was commonly discovered in forested places. S. nudiseta was collected only from corpses found in an indoor death scene. [ABSTRACT FROM AUTHOR]