Chrysomya Pinguis Research Articles

The complete mitochondria genome of Chrysomya pinguis (Diptera: Calliphoridae)

Chrysomya pinguis (Ch. pinguis) belongs to blowfly species of great medical and forensic importance. In this study, we report the complete mitochondrial genome of the Ch. pinguis for species identification. The 38 genes presented in the 15,838 bp circular genome has been found in a typical Metazoan genome, of which there are 23 transfer RNA genes, 13 protein-coding genes and 2 ribosomal RNA genes. In addition, there is a non-coding A + T-rich region between one and another tRNA-Ile. The array of the genes is similar to that discovered in other insects. The overall base compositions of A, G, C and T are 38.72%, 9.86%, 14.07% and 37.35% respectively. This study contributes to the availability of dipteran mitochondrial genomes and provides the first complete mitochondrial genome of Ch. pinguis for entomologists to identify diagnostic regions for species identifications and phylogenetic analysis.

Temperature adaptation in Chrysomya megacephala and Chrysomya pinguis, two blow fly species of forensic significance

AbstractChrysomya megacephala (Fabricius) (Diptera: Calliphoridae) is a common and forensically important blow fly species in the Oriental region. However, in the higher mountain regions and on winter days, its habitats are occupied by a closely related species, Chrysomya pinguis (Walker). The resources that the two species employ to survive are very similar and competition between the species may be one of the factors that trigger differentiation of their behaviors. We conducted experiments to examine how these two closely related species may have adapted to different temperature regimes to avoid competition. Several adult and immature parameters were assessed, such as fecundity, locomotor ability, hatching ratio, larval survivorship, and eclosion ratio. Results indicate that species show specific diapause at high temperature (38 °C), larval survivorship of Ch. megacephala was significantly better than that of Ch. pinguis. Conversely, at low temperature (15 °C), adult locomotor ability was better for Ch. pinguis than for Ch. megacephala. The results indicate that the two species may have evolved different temperature adaptation strategies to avoid competition. In mixed‐species larval rearing experiments, competition between Ch. pinguis and Ch. megacephala was observed: at higher temperature (30 °C), the immature performance index of Ch. megacephala was significantly increased when compared to that in single‐species culture, whereas the index of Ch. pinguis was decreased. These data are consistent with the idea that tolerance for higher temperature conditions would allow larvae of Ch. megacephala to gain a competitive advantage over Ch. pinguis in certain habitats. These results may help to explain their current distribution in the environment and provide more biological information on these forensically important species.

Using the Developmental GeneBicoidto Identify Species of Forensically Important Blowflies (Diptera: Calliphoridae)

Identifying species of insects used to estimate postmortem interval (PMI) is a major subject in forensic entomology. Because forensic insect specimens are morphologically uniform and are obtained at various developmental stages, DNA markers are greatly needed. To develop new autosomal DNA markers to identify species, partial genomic sequences of the bicoid (bcd) genes, containing the homeobox and its flanking sequences, from 12 blowfly species (Aldrichina grahami, Calliphora vicina, Calliphora lata, Triceratopyga calliphoroides, Chrysomya megacephala, Chrysomya pinguis, Phormia regina, Lucilia ampullacea, Lucilia caesar, Lucilia illustris, Hemipyrellia ligurriens and Lucilia sericata; Calliphoridae: Diptera) were determined and analyzed. This study first sequenced the ten blowfly species other than C. vicina and L. sericata. Based on the bcd sequences of these 12 blowfly species, a phylogenetic tree was constructed that discriminates the subfamilies of Calliphoridae (Luciliinae, Chrysomyinae, and Calliphorinae) and most blowfly species. Even partial genomic sequences of about 500 bp can distinguish most blowfly species. The short intron 2 and coding sequences downstream of the bcd homeobox in exon 3 could be utilized to develop DNA markers for forensic applications. These gene sequences are important in the evolution of insect developmental biology and are potentially useful for identifying insect species in forensic science.

English

The blow fly is considered to be a medically-important insect worldwide. This review is a compilation of the currently known occurrence of blow fly species in Thailand, the fly’s medical importance and its morphological identification in all stages. So far, the 93 blow fly species identified belong to 9 subfamilies, including Subfamily Ameniinae, Calliphoridae, Luciliinae, Phumosiinae, Polleniinae, Bengaliinae, Auchmeromyiinae, Chrysomyinae and Rhiniinae. There are nine species including Chrysomya megacephala, Chrysomya chani, Chrysomya pinguis, Chrysomya bezziana, Achoetandrus rufifacies, Achoetandrus villeneuvi, Ceylonomyia nigripes, Hemipyrellia ligurriens and Lucilia cuprina, which have been documented already as medically important species in Thailand. According to all cited reports, C. megacephala is the most abundant species. Documents related to morphological identification of all stages of important blow fly species and their medical importance also are summarized, based upon reports from only Thailand. KeywordsBlow fly, Distribution, Identification, Medical Importance, Thailand International Journal of Parasitology Research ISSN: 0975-3702 & E-ISSN: 0975-9182, Volume 4, Issue 1, 2012 Introduction Thailand is a country located at the centre of the Indochina peninsula in Southeast Asia. It comprises 77 provinces that cover 6 regions by location and its hot and humid climate supports a variety of tropical ecosystems. Unlike the temperate zone, tropical ecosystems provide wider niches for the survival of organisms, which are thus able to support a much larger variety of plant, animal and microbe species. Blow flies form one of many insect groups that are commonly found in the country and their families are classified as follows: Kingdom Metazoa, Phylum Arthropoda, Class Hexapoda, Order Diptera, Suborder Brachycera and Family Calliphoridae. They are characterized typically as being metallic blue, green, purple, or non metallic in color and they vary in size [1]. Blow fly larvae serve as carrion feeders that play an important role in recycling organic materials in the ecosystem. Furthermore, adults have been reported as pollinators of mango flowers in Australia [2] and Taiwan [3]. Over 1,450 blow fly species are distributed over all continents in the world, except Antarctica [1]. Based on citation in this review, the first document related blow fly was reportedly found in 1976 [4] and the first taxonomic key for blow flies (subfamily Calliphoridae) in Thailand was documented by Tumrasvin et al, [5]. The first text book relating to medically-important blow fly species of Thailand was written in the Thai language in 2010 by Associate Professor Dr. Kom Sukontason and Associate Professor Dr. Kabkaew Sukontason [6]. Over the past 36 years, there have been many scientific articles that demonstrate blow fly occurrence in several parts of Thailand as well as the fly’s biological aspects and medical importance. Although this information has increased gradually, it is still scattered. Therefore, the objectives of this review were to gather and update all information on blow flies, based upon scientific reports from only Thailand and the experience of this author. This review emphasized on mainly 3 aspects, including (i) the occurrence of blow fly species, (ii) morphological identification of all stages and (iii) their medical imCitation: Nophawan Bunchu (2012) Blow fly (Diptera: Calliphoridae) in Thailand: Distribution, Morphological Identification and Medical Importance Appraisals. International Journal of Parasitology Research, ISSN: 0975-3702 & E-ISSN: 0975-9182, Volume 4, Issue 1, pp.-57-64. Copyright: Copyright©2012 Nophawan Bunchu. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.

External morphology of Chrysomya pinguis (Walker) (Diptera: Calliphoridae) revealed by scanning electron microscopy

The external morphology of the adult female blow fly, Chrysomya pinguis (Walker, 1858), was examined using scanning electron microscopy. Ultrastructure of the compound eye, ocellus, antenna, palpus, spiracles and portions of the thorax was highlighted. A great difference was observed in sculpture patterns of the corneal lens surface of the ommatidia of the compound eye and that of the ocelli, with the former being densely pustulate and the latter extremely sinuous. Several sensilla types were observed in this study including: sensilla chaetica, sensilla trichodea, sensilla basiconica and sensilla coeloconica. Their probable functions are discussed with reference to other literature. Morphological information about C. pinguis that was revealed in this study allows us to know such types of structures in much better detail and may eventually provide a basis for understanding some of the biological behavior of this fly species in the future.

Ultrastructure of adhesive device in fly in families calliphoridae, muscidae and sarcophagidae, and their implication as mechanical carriers of pathogens

The ultrastructure of adhesive device or the pulvilli, pad-like structure between the tarsal claws of the legs, is presented in the blowfly (Calliphoridae), housefly and relatives (Muscidae), and flesh fly (Sarcophagidae) through scanning electron microscopy. The blowfly species were Chrysomya chani, Chrysomya nigripes, Chrysomya pinguis, and Chrysomya villeneuvi; while those of the housefly and relatives were Musca domestica and Hydrotaea chalcogaster, respectively. Fresh fly species included Boettcherisca peregrina and Liosarcophaga dux. Numerous tenent setae were observed on the ventral side of the pulvilli. Two features of the tip of the tenent setae were found as a spatula-like (in C. chani, C. pinguis, C. nigripes, M. domestica, H. chalcogaster, B. peregrina, and L. dux) and spoon-like tip (in C. villeneuvi). Transmission electron microscopy of the tenent setae in M. domestica revealed the electron-lucent centrally located, suggesting an adhesive substance. These results provided anatomical information that allow us to not only understand the successful attachment of flies to smooth surfaces but also clarify their role as a mechanical carrier of microorganisms.

Surface ultrastructure of prestomal teeth of some flies in the families Calliphoridae, Muscidae and Sarcophagidae

Prestomal teeth of flies in the families Calliphoridae (Chrysomya pinguis, Chrysomya villeneuvi, and Chrysomya chani), Muscidae (Hydrotaea (= Ophyra) chalcogaster) and Sarcophagidae (Boettcherisca peregrina) were presented using scanning electron microscopy. The slight to deep bifurcation of the tips of their teeth were similarly observed in all species examined. The anatomical feature of prestomal teeth of the flies examined may contribute to the understanding of their feeding behavior and the medical importance of their role in the future.

Species identification of the forensically important flies in Iwate prefecture, Japan based on mitochondrial cytochrome oxidase gene subunit I ( COI) sequences

Molecular biological species identification of forensically important flies distributed in Iwate prefecture, Japan, was carried out, and the utility of this method was evaluated. The dipteran nymphs that were early colonizers on the corpse were reared to adult and morphologically identified. Meanwhile they were sequenced over a 304 base pair region of the mitochondrial cytochrome oxidase gene subunit I ( COI). Six species belonging three genera of Calliphoridae ( Calliphora lata, C. vicina, Lucilia cuprina, L. illustris, L. sericata, Chrysomya pinguis) and two species of Sarcophagidae ( Parasarcophaga crassipalpis, P. similis) were collected and identified. Each fly had somewhat different ecological features such as seasonal dominance and habitat. The COI sequences of each species were unique and distinguishable from each other, although they showed high homology. Species identification from immature diptera by the DNA sequences was simple and time-saving because there was no need to wait for adult emergence or knowledge of morphological keys, and it provided information about not only postmortem interval but also seasonal and environmental conditions surrounding the corpse.

Molecular identification of forensically important blow fly species (Diptera: Calliphoridae) in Taiwan.

Forensic entomology is a discipline that mainly uses insects collected in and around corpses to estimate the post-mortem interval in medicocriminal investigations. Among all scavenger and necrophagous insect groups that are related to corpses, blow flies (Diptera: Calliphoridae) are probably most important, not only because they occur in abundant numbers but also because they are one of the earliest groups to find corpses. However, most entomological evidence is strongly dependent on accurate species identification. Because identification allows the proper developmental data and distribution ranges to be applied in criminal investigations, species in Taiwan were surveyed from early 2000 and were identified using molecular data. Currently, eight species have been identified: Chrysomya megacephala (Fabricius), Chrysomya pinguis (Walker), Chrysomya rufifacies (Macquart), Hemipyrellia ligurriens (Wiedemann), Lucilia bazini Séguy, Lucilia cuprina (Wiedemann), Lucilia hainanensis Fan, and Lucilia prophyrina (Walker). We focused on classifying these blow fly species to establish a knowledge basis for further forensic entomological research in Taiwan. Because molecular data are helpful in identifying insect specimens, especially when no specimen of suitable condition for morphological identification is obtained, we extracted mitochondrial cytochrome oxidase subunit I (COI) DNA of the preceding blow fly species to study its application value for their differentiation. The cloning and sequencing of the COI gene (approximately 1,588 base pairs) of these eight species were completed, and the data were analyzed. Preliminary results revealed the high support of congeneric groupings of species by using COI data; these sequences were also shown to be highly conserved within the same species. To actually use the database of COI sequences under various specimen conditions, specific primers were also applied for different insect stages, different segments of adults, and specimens preserved for various times. A molecular primer key was ultimately constructed for the purpose of rapid and accurate species identification at the molecular level regardless of which stage or which part of a blow fly specimen is collected.

Polytene chromosomes of monogenic and amphogenic Chrysomya species (Calliphoridae, Diptera): analysis of banding patterns and in situ hybridization with Drosophila sex determining gene sequences.

Standard maps for the five banded polytene chromosomes found in trichogen cell nuclei of the monogenic blowfly Chrysomya rufifacies and the amphogenic Chrysomya pinguis are presented. The chromosomes are highly homologous in the two species; differences in banding patterns are predominantly caused by one pericentric and ten paracentric inversions. In chromosome 5 of the amphogenic Chrysomya phaonis, also analysed in this paper, an additional paracentric inversion was observed. The distribution of species specific inversions indicates that the monogenic C. rufifacies is phylogenetically older than the amphogenic species. The maternal sex realizer locus F'/f on polytene chromosome 5 of C. rufifacies is not associated with a structural heterozygosity. Chromosome pair 6 of C. rufifacies and the sex chromosome pair of C. pinguis are under-replicated in polytene nuclei; they consist of irregular chromatin granules, frequently associated with nucleolus material. Evolution of heteromorphic sex chromosomes in Chrysomya is probably correlated with heterochromatin accumulation. A search for sex determining genes in Chrysomya was initiated using sex determining sequences from Drosophila melanogaster for in situ hybridization. The polytene band 41A1 on chromosome 5 of monogenic and amphogenic Chrysomya species contains sequences homologous to the maternal sex determining gene daughterless (da). Homology to the zygotic gene Sex-lethal (Sxl) of Drosophila is detected in band 39A1 on chromosome 5 of C. rufifacies. The findings reported here are the first evidence for a possible homology between the da gene of Drosophila and the maternal sex realizer F' of C. rufifacies. An hypothesis for the evolution of the maternal effect sex determination of C. rufifacies is proposed.

新潟県のハエについて

In 1955, with the assistance of 16 health centers in Niigata Prefecture, flies of medical importance were collected by means of a cage or ribbon trap throughout the year. They totalled 30, 751 specimens consisting of 18, 181 outdoor flies (15, 308, collected in an open field, plus 2, 873, trapped in such mountain areas as Kushigatayama, Ginzan-daira and Oze) and 12, 570 indoor ones. As shown in the classification table, they were classified into 10 families, 32 genera and 61 species. To describe the fly fauna, in family Muscidae, Muscina angustifrons held a superiority in every region. In family Anthomyiidae, both Fannia and Qphyra species were omnipresent, while Ophyra nigra was distributed more densely in a piedmont rather than in a plain. In Greenbottle flies of family Calliphoridae, Phaenica sericata ranked first in inhabitation number in most of the regions. A distribution of P. sericata >Lucilia illustris>L. caesar was observed in most of the region and that of P. sericata>L. caesar>L. illustris in some districts. An uncommon distribution of L. caesar>P. sericata was seen in Sanjo and Koide districts, that of P. sericata>L. caesar>P. cuprina, L. illustris in Niitsu district, and that of P. sericata>L. caesar>Hemipyrelia ligurriens>L. illustris in Sado Island. And L. papuensis, which is usually seen in a mountain area only, inhabited as a common species in Sado Island. Phormia regina and Protophormia terae-novae were found to inhibit in Naoetsu district. This may be of some help in the investigations of such an epidemic as polio. Of Sarcophagid flies, 14 species were discovered in Niigata Prefecture and showed a distribution of Sarcophaga peregrina>S. melanura>S. similis common to every district. It was interesting that S. tsushimae was discovered in Sado Island as well as in Tsushima, and S. polystylata originally discovered in Peiping was found out in a coastal plain along the Japan Sea. Concerning the fauna of indoor flies trapped by a ribbon, a distribution of Musca domestica>Fannia canicularis type was seen in some districts and that of the reverse type in others. Other species of flies were also found in small numbers. It, therefore, followed that many species of flies would invade indoors. Generally most of the flies of medical importance made three appearance in large numbers in spring, summer and autumn. Some species of family Calliphoridae, for instance, Calliphorinii, made their appearance in spring and autumn, and hid themselves in summer while Lucilia species are very common chiefly in summer, as flies of Sarcophagid flies did. Scopeuma stercorarium and Stenodryomyza formosa appears in early spring and late autumn, while Helomyza modesta in late autumn and early winter. Any summer mountains abunded with flies, but a fly fauna in them was fairly different from that in a plain. To enter into details, in both Kushigata-yama and Ginzan-daira, Chrysomya pinguis predominated in numbers; P. sericata hardly made its appearance; L. caesar was relatively numerous; L. papuensis was active as a common species in a mountain as its name suggests, and Calliphora lata and Aldrichina grahami, which, in a plain, do not usually make their appearance during summer, led an active life. Of family Muscidae, Muscina angustifrons was seen most frequently as a common species in a mountain region, and also M. assimilis and M. pabulorum were found easily. Of family Anthomyiidae, Ophyra nigra was distributed comparatively densely, and Hylemyia platura, which is distributed all over the country, was also discovered in the mountain areas. Scopeuma stercorarium and Stenodryomyza formosa were not trapped in those places. As for Sarcophagid flies, a distribution of S. peregrina>S. melanura>S. similis commonly observable in a plain, did not stand for the mountain areas, that is, a distribution of S. peregrina>S. albiceps>S. similis>S. me