Occurrence of Blow Fly Species (Diptera: Calliphoridae) in Phitsanulok Province, Northern Thailand

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.

Effects of human contraceptive on reproduction and offspring in Chrysomya megacephala

OBJECTIVE@#To investigate the effect of human contraceptive (HC) as ability to suppress the reproductive success of blow fly, Chrysomya megacephala (Fabricius) (C. megacephala) and offspring under controlled laboratory conditions.@*METHODS@#Adult C. megacephala were fed with low (0.036 mg/mL) and high dose (0.072 mg/mL) HC (Microgest®, Thailand), containing levonorgestrel and ethinyl estradiol, in their drinking water for 7 days. Three experiments were set; experiment I with fed only in parental males, experiment II with fed only in parental females and experiment III with fed in both males and females. All experiments were then maintained for 3 generations after crossing and inbreeding.@*RESULTS@#A lower ovariole production and less fully mature ovarioles were evident in F1, F2 and F3 than control when parent males, females and both had been fed with high dose HC. Cellular changes during spermatogenesis in F1, F2 and F3 testes was confirmed using transmission electron microscopy (TEM), showing the low level of condensed chromatin, necrotic chromatin, irregularities and degenerated nuclear envelope in the nucleus. In the cytoplasm, mitochondrial swelling, rough endoplasmic reticulum swelling as well as vacuolated cytoplasm were noticed. As for the sperm per se, we found the degenerated nuclei and/or incomplete mitochondrial derivative, axoneme and vacuolated flagella. Regarding deformity in F1, F2 and F3 ovariole, ultrastructural alteration observed by scanning electron microscopy (SEM) included malformations involving fragile enveloping peritoneal sheath, cracked ovarioles, peel away chorion, crumbled eggshell and incomplete development; whereas TEM presented malformed and disorganized mass of cells, proteic yolk granules and vacuolated vesicles.@*CONCLUSIONS@#Administer of HC to adult C. megacephala caused ovariole reduction, less matured ovariole and affected cellular changes in testes and ovariole of offspring up to F3.

Study of insect succession and rate of decomposition on a partially burned pig carcass in an oil palm plantation in Malaysia

Insects found associated with corpse can be used as one of the indicators in estimating postmortem interval (PMI). The objective of this study was to compare the stages of decomposition and faunal succession between a partially burnt pig (Sus scrofa Linnaeus) and natural pig (as control). The burning simulated a real crime whereby the victim was burnt by murderer. Two young pigs weighed approximately 10 kg were used in this study. Both pigs died from pneumonia and immediately placed in an oil palm plantation near a pig farm in Tanjung Sepat, Selangor, Malaysia. One pig was partially burnt by 1-liter petrol while the other served as control. Both carcasses were visited twice per day for the first week and once thereafter. Adult flies and larvae on the carcasses were collected and later processed in a forensic entomology laboratory. Results showed that there was no significant difference between the rate of decomposition and sequence of faunal succession on both pig carcasses. Both carcasses were completely decomposed to remain stage after nine days. The species of flies visiting the pig carcasses consisted of blow flies (Chrysomya megacephala, Chrysomya rufifacies, Hemipyrellia ligurriens), flesh fly (Sarcophagidae.), muscid fly (Ophyra spinigera), soldier fly (Hermetia illucens), coffin fly (Phoridae) and scavenger fly (Sepsidae). The only difference noted was in the number of adult flies, whereby more flies were seen in the control carcass. Faunal succession on both pig carcasses was in the following sequence: Calliphoridae, Sarcophagidae, Muscidae, Phoridae and lastly Stratiomyidae. However, there was overlap in the appearance of members of these families. Blowflies continued to oviposit on both carcasses. Hence postmortem interval (PMI) can still be estimated from the partially burnt pig carcass.

On the occurrence of Musca domestica L oviposition activity on pig carcass in peninsular Malaysia

A forensic entomological study conducted in an oil palm plantation in Tanjung Sepat, Selangor, Malaysia on 3 August 2007 revealed that a housefly, Musca domestica Linnaeus oviposited its eggs on a freshly dead pig. This finding indicated that housefly might play an important role in forensic investigation in determining post-mortem interval (PMI), although it was not yet found in human corpses or any animal carrion. This preliminary paper presented a first record of Musca domestica eggs found on animal carcass in the country.

A new record of Fannia prisca Stein, 1918 (Diptera:Fanniidae) from peninsular Malaysia

Fannia prisca Stein, 1918 is newly recorded from peninsular Malaysia. This record is based on 4 male specimens from Mount Berembun, Brinchang, Cameron Highland, Pahang state, peninsular Malaysia. It is previously recorded from China, Mongolia, Korea, Japan, Taiwan, Bonin Island, Thailand and oriental region. The male of Fannia prisca can be differentiated from male Fannia scalaris by the following features: for F. prisca, mid-coxa without spine; mid-tibia normal or without stout triangular ventral projection; and hind tibia usually with 2 av, while F. scalaris has several stout hook-like spines on the anterior margin; mid-tibia with stout triangular ventral projection and hind tibia usually with 3 av. Both F. prisca and F. scalaris can be differentiated from Fannia leucosticta by looking at its hind tibia, which only has 1 av.

A new record of Bengalia emarginata Malloch, 1927 (Diptera: Calliphoridae) from Malaysia

During a forensic entomological study conducted at an oil palm plantation in Tanjung Sepat, Kuala Langat, Selangor, a Bengalia emarginata Malloch, 1927 (Diptera: Calliphoridae: Calliphorinae: Bengalini) was collected for the first time. Two adults were collected nearby the pig carcass by the first author and identified by the second. Prior to this finding, nine species of Bengalia were recorded from peninsular Malaysia or Borneo. Male of B. emarginata are different from Bengalia varicolor Fabricious by the following characters: Sternite 5 projection rounded with small identation and mid tibia double-fringed in ventral surface.

First report of the signal fly, Scholastes sp. (Diptera:Platystomatidae) visiting animal carcasses in Malaysia

Signal fly, Scholastes sp. (Diptera: Platystomatidae) was observed associated with animal carcasses in Malaysia. The first observation was on a monkey carcass, which was killed by using a handgun and immediately placed in a forested area in Gombak, Selangor while the second observation was on a pig that died of natural causes and whose carcass was placed in an oil palm plantation in Tanjung Sepat, Selangor. Both animal carcasses were visited by Scholastes sp. flies during the fresh decomposition period. However, the role Scholastes flies in the decomposition process remains unknown. In this paper, we report the occurrence of Scholastes sp. on animal carcasses in Malaysia for the first time.