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The genus Hemerodromia in Thailand is revised and full descriptions and keys are provided for all 25 species. Twenty new species are recognised: H. alphalutea sp. nov., H. anisoserrata sp. nov., H. anomala sp. nov., H. attenuata sp. nov., H betalutea sp. nov., H. conspecta sp. nov., H. deltalutea sp. nov., H. deminuta sp. nov., H. demissa sp. nov., H. epsilutea sp. nov., H. etalutea sp. nov., H. gammalutea sp. nov., H. isochita sp. nov., H. namtokhinpoon sp. nov., H. ocellata sp. nov., H. oriens sp. nov., H. phahompokensis sp. nov., H. songsee sp. nov., H. systoechon sp. nov. and H. zetalutea sp. nov. Five species known previously from China are recognised: H. acutata Grootaert, Yang & Saigusa, H. flaviventris Yang & Yang, H. furcata Grootaert, Yang & Saigusa, H. fusca Yang & Yang and H. yunnanensis Yang & Yang. Hemerodromia songsee sp. nov. and H. fusca Yang & Yang are also recorded from Vietnam. Distribution maps of all species are presented. Four categories of distribution patterns of apparently endemic species were identified in (1) the northern mountains (2) the northern lowlands (3) the south, and (4) east of Thailand. Some lowland species with wide distributions in eastern Asia were interpreted as 'old Oriental elements'. Other montane species have wide distributions extending between the Himalayas and southeast China. Three lowland species have an apparently obligate association with alkaline, mineralised water courses where tufa deposition was evident. Tufa-linked assemblages of Hemerodromia may indicate a previously unrecognised and potentially diverse habitat for aquatic Empididae in Southeast Asia. Major historical factors determining contemporary distribution patterns were analysed in reference to a Climate History Model (Plant et al. 2012) and included (i) latitudinal migrations in response to climatically induced changes in the distribution of habitat (ii) radiation of high-elevation endemics from more widespread lowland forms (iii) historical connectivity and fragmentation of hydrological networks with possible marooning of taxa in stable tufa spring systems (iv) persistence of lowland forms in climatically 'buffered' stream environments during progressive aridification. Analysis of sampling methodology concluded that hand collecting was 2,000X more efficient at collecting numbers of Hemerodromia with a species discovery rate 775X greater than that with passive trapping methods (Malaise, flight interception and pan traps etc.) although both approaches are needed for full assessment of species richness. Consideration of the climatic, ecological and biogeographic complexity of tropical Southeast Asia suggests that an extremely rich Hemerodromia fauna awaits discovery in the region.

Blow flies of the genus Hypopygiopsis are considered forensically important. In Thailand, four Hypopygiopsis species coexist, i.e., Hypopygiopsis fumipennis, Hypopygiopsis infumata, Hypopygiopsis violacea and Hypopygiopsis tumrasvini. In this study, the ontogeny and developmental rate of H. tumrasvini eggs, larvae and pupae were determined in the laboratory chamber reared at 25.0 ± 2.0°C and 80.0 ± 5.0% RH. Larvae emerged from eggs 10-12 h after deposition. Mean length of the first, second, third (feeding phase), third (post-feeding phase) instars and puparia were 3.5 ± 1.1, 7.2 ± 1.1, 13.5 ± 1.8, 12.5 ± 0.5 and 9.0 ± 0.7 mm, respectively. The median development time for first, second, third instar (feeding phase), third instar (post-feeding phase) and pupariation period was 8 h, 10 h, 34 h, 22 d and 9-10 d, respectively. Developmental curve of the larval length indicated the rapid progression from 0 until 40 h from the first instar until the feeding third instar. Video recording of pupariation revealed the development of pupal respiratory horn beneath the larval integument at 27.0 h; whereas it protruded through the orifice of the integument at 27.5 h.

The Oriental latrine fly, Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) and the house fly, Musca domestica L., (Diptera: Muscidae) are synanthropic flies which are adapted to live in close association with human habitations, thereby making them likely mechanical vectors of several pathogens to humans. There were two main aims of this study. The first aim was to determine the prevalence of these two fly species from five types of human habitations including: fresh-food markets, garbage piles, restaurants, school cafeterias and paddy fields, in the Muang Ubon Ratchathani and Warinchamrap districts of Ubon Ratchathani province of Northeast Thailand. Flies collection were conducted monthly from September 2010-October 2011 using a reconstructable funnel trap, containing 1 day-tainted beef offal as bait. A total of 7 750 flies (6 401 C. megacephala and 1 349 M.domestica) were collected. The second aim was to examine the potential of these flies to carry pathogenic bacteria. Bacteria were isolated from 994 individual flies collected using a sweep net (555 C. megacephala and 439 M. domestica). A total of 15 bacterial genera were isolated from the external surfaces, comprising ten genera of gram-negative bacteria and five gram-positive bacteria. The most common bacteria isolated from both species were coagulase-negative staphylococci, followed by Streptococcus group D non-enterococci. Human pathogenic enteric bacteria isolated were Salmonella sp., Shigella sp., Escherichia coli O157:H7, Salmonella typhi, Bacillus sp., and Enterococcus sp., of which S. typhi is the first report of isolation from these fly species. Other human pathogens included Staphylococcus aureus and Pseudomonas aeruginosa. Not only were the number of C. megacephala positive for bacteria significantly higher than for M. domestica, but they were also carrying ~11-12 times greater bacterial load than M. domestica. These data suggest that both fly species should be considered potential mechanical vectors of bacterial pathogens associated with human habitations year-round in this region of Northeast Thailand.

The genus Hybos Meigen in Thailand is revised and full descriptions and keys provided for all 41 species. Thirty-four new species are recognized: H. aceriformis sp. nov., H. ancyclochiles sp. nov., H. anisoserratus sp. nov., H. bispinatus sp. nov., H. chaweewani sp. nov., H. daugeroni sp. nov., H. divisus sp. nov., H. grootaerti sp. nov., H. hylobates sp. nov., H. inthanonensis sp. nov., H. kaluang sp. nov., H. khamfui sp. nov., H. konkaogwang sp. nov., H. lannaensis sp. nov., H. mangraii sp. nov., H. meeamnat sp. nov., H. men sp. nov., H. merzi sp. nov., H. ngachang sp. nov., H. paknok sp. nov., H. phahompokensis sp. nov., H. pisadaanus sp. nov., H. saenmueangmai sp. nov., H. shamshevi sp. nov., H. sinclairi sp. nov., H. songbai sp. nov., H. steatopygus sp. nov., H. stigmaticus sp. nov., H. subapicalis sp. nov., H. tetricus sp. nov., H. thaosaeo sp. nov., H. thepkaisoni sp. nov., H. tilokarati sp. nov., H. yungyak sp. nov. Seven species known previously from China are recognized: H. ancistroides Yang & Yang, H. apicihamatus Yang & Yang, H. longus Yang & Yang, H. particularis Yang, Yang & Hu, H. serratus Yang & Yang, H. xishuangbannaensis Yang & Yang, and H. zhejiangensis Yang & Yang. Eight informal species-groups are tentatively proposed based on characters of male and female terminalia and attention is drawn to the many previously overlooked taxonomically useful characters of the female terminalia. Distribution maps of all species are presented and distributions categorised as ‘widespread’, ‘eastern’, ‘southern’, north-eastern’ or ‘northern and western’. Species richness and endemicity are greatest in mid to high elevation evergreen forest biotopes of the northern mountains and areas of endemism are identified on the Luang Prabang, Daen Lao, Thanon Thong-chai ranges and on the Isaan Plateau at least. Adult phenology is correlated with the rainy season in many species and preliminary analyses reveal that many high-elevation species have short emergence periods and restricted distributions, whereas some lowland species have longer emergence periods and wider distributions.

Based on the current forensic importance of blow flies (Diptera: Calliphoridae), their biological aspects have been studied increasingly worldwide. The blow fly fauna in Phitsanulok Province, Northern Thailand was studied from May 2009 to April 2010 in the residential, agricultural, mountainous and forested areas of Muang, Wat Bot, Nakhon Thai and Wang Thong districts, respectively, in order to know the occurrence of blow flies in this province. Collections were carried out monthly using commercial funnel fly traps and sweeping methods, with 1-day tainted pork viscera as bait. Identification of adult blow flies exhibited 14 634 specimens, comprising of 5 subfamilies, 14 genera and 36 species. Chrysomya megacephala (Fabricius, 1794) and Achoetandrus rufifacies (Macquart, 1843) were the most and second most abundant species trapped, respectively. These two species of carrion flies prevailed in all the types of land investigated. We calculated and compared the diversity indices, species evenness and richness, and similarity coefficients of the blow fly species in various areas. The data from this study may be used to identify the potential of forensicallyimportant fly species within Phitsanulok Province and fulfill the information on blow fly fauna in Thailand.

The blow fly, Chrysomya megacephala (Fabricius), and house fly, Musca domestica L., are medically and forensically important flies. The population dynamic of these flies is essential for both control and forensical aspects. The aim of this study was to investigate the climatic and physical factors affecting the population trend of both species in Chiang Mai province, northern Thailand, using the Geographic Information System (GIS). Based on systematic random sampling, 18 study sites were selected in three districts (Mueang Chiang Mai, Mae Rim, and Hang Dong). Six land use types were involved in the study sites, i.e., disturbed mixed deciduous, mixed deciduous forest, mixed orchard, lowland village, city, and paddy field. Adult flies were sampled every 2 weeks using an in-house prototype reconstructable funnel trap. Two types of bait were used--one with fresh beef viscera for luring M. domestica and the other with 1-day tainted beef viscera for luring C. megacephala. Collections were conducted from May 2009 to May 2010, and analysis of climatic factors (temperature, relative humidity, and light intensity) was carried out. Correlation bivariate analysis was performed initially to determine the relationship between climatic factors and the number of flies. Consequently, an ordinary co-kriging approach, in ArcGIS 9.2, was performed to predict the spatial distribution of flies with land use and climatic factors as co-variables. A total of 63,158 flies were captured, with C. megacephala being the most common species collected (68.37%), while only 1.3% were M. domestica, thus proving that C. megacephala was the most abundant species in several land use types. A significantly higher number of females than males was found in both species. Fly populations can be collected throughout most of the year with a peak in late summer, which shows a positive relation to temperature but negative correlation with relative humidity. C. megacephala was predicted to be abundant in every land use type, from lowland to forested areas, while the density of house fly was association with altitude and land use types.

Forensically important flesh fly species in Thailand have been investigated for their larval morphology and developmental rate to increase the forensic entomology database in Thailand and nearby countries. Sarcophaga (Liosarcophaga) dux Thomson, Sarcophaga (Liopygia) ruficornis (Fabricius), and Sarcophaga (Boettcherisca) peregrina (Robineau-Desvoidy) are the species of greatest forensic importance. The third instars of these species are similar in morphological appearance, making it difficult or impossible to differentiate between them based on external morphological characteristics. This study compares these important characteristics and reveals that the most distinctive is the posterior spiracle, followed by the number of papillae on the anterior spiracle. For confirmation of these species, the unique characteristics of adult males are also shown for accurate identification. Both the third instar and adult male characteristics are keys to identifying these species. In addition, the developmental rate of S. dux was examined in northern Thailand during 2002-2003 under natural ambient temperature (approximately 24-28 degrees C) and a natural light/dark photoperiod (approximately 12:12 h), indicating relatively rapid larval development in summer (March-June), pre-pupae (stop moving) initiated at 72 h. In the rainy season (July-October), pre-pupae initiated at 72 or 96 h, whereas pre-pupae initiated at 96 h in winter.

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.

Observations on the ultrastructure of the third instar larva and puparium of the Old World screw-worm fly, Chrysomya bezziana, are presented utilizing both light microscopy (LM) and scanning electron microscopy (SEM). Results of this study indicate that the shape of the intersegmental spines between the pro- and mesothorax markedly differ from other blow fly species (Chrysomya megacephala, Chrysomya rufifacies, Chrysomya nigripes, Lucilia cuprina) in being broad-based with sharp recurved tips. Other characters such as the posterior spiracles, number of papillae on the anterior spiracles, oral grooves, and posterior spiracular hairs also differ. The strong and robust mouthhooks may explain the ability of larvae to penetrate deeply into human tissues. Perforated sieve plates covered with antler-like projections were observed within the anterior spiracles of the puparium of C. bezziana. The posterior spiracular discs each bear three spiracular slits with approximately 2-microm wide openings that were viewed either open or closed by a membrane underneath. This study expands our knowledge of the fine details of the external morphology of both the third instar larva and puparium of C. bezziana, which is an obligatory myiasis-producing species in many regions. A key to differentiate the third instar of C. bezziana from other blow flies in Thailand is given.

The authors report herein the entomological evidence from the first documented forensic floating corpse in Thailand. The male remains of unknown name and age was found in the waterside of a reservoir in Lampang province, northern Thailand. Approximately 13-16 wounds resulting from sharp-edged material were found on the body. Numerous third-instar of blowflies Chrysomya megacephala (F) and Chrysomya rufifacies Macquart (Diptera: Calliphoridae) were collected, and the entomological evidence of the latter species could be used to estimate approximately 7 days of the postmortem interval. This is the first report of C. megacephala as forensic important fly species in Thailand. Additional research is needed to ascertain the effects of water on the succession and development of both fly species subsequently coming to associate with a corpse so treated in Thailand.

One complete generation of the sciomyzid fly, S. spangleri, was on the average 27.90 days at 25 +/- 3 degrees C. The egg stage lasted 3.55 days. The first, second and third instar larvae lasted 4.35, 2.95 and 4.45 respectively when fed with live snails, Australorbis glabratus. Pupae floated on the water surface for 8 days until they emerged as adults. The longevity of adults fed with crushed snails, dried milk, brewer's yeast and honey average 199.95 days for females and 136.80 days for males. Under these conditions the average number of eggs laid per female was 414.70.

The morphological, life-cycle, and experimental studies of Megaselia scalaris were reported. This fly is commonly found both in urban and rural areas in Thailand. It is easily identified and the humped thorax was the most distinct characteristic of the adult. The egg to the adult stage and the life span required 15 to 20 days for the male and 16 to 22 days for the female. Experimental attempts to induce myiasis infection in laboratory animals were unsuccessful.