DNA-barcoding of forensically important blow flies (Diptera: Calliphoridae) in the Caribbean Region

Myiasis in European hedgehogs (Erinaceus europaeus)

Myiasis due to parasitic fly larvae (maggots) can have major consequences for animal health and welfare. The European hedgehog Erinaceus europaeus is frequently presented in rehabilitation centres and veterinary practices due to health problems, including myiasis. In the present study, 557 hedgehogs presented at wildlife rehabilitation centres in Northern Germany during 2018-2021 were examined for the presence of dipteran eggs and larvae. Overall, 15.6% of animals carried fly eggs and/or larvae. Four different dipteran species were identified by PCR and sequencing of the internal transcribed spacer 2 (ITS-2) region. Lucilia sericata was detected on 25.3% [22/87] of affected hedgehogs, followed by Calliphora vicina (12.6% [11/87]), Lucilia ampullacea (11.5% [10/87]) and Lucilia caesar (9.2% [8/87]). Myiasis prevalence was significantly higher during the summer compared to spring and autumn. Fly eggs were found all over the body, while larvae were detected most frequently in the body's natural orifices and in wounds. Regarding rehabilitation success, myiasis occurred significantly more frequently in animals that died or were euthanized compared to those released back into the wild. Although the high death rate probably arose in combination with underlying disease, this illustrates that myiasis represents a serious health issue that should be diagnosed and treated immediately.

Molecular identification of immature stages of medically important fly species, Puducherry, South India: a preliminary study

Flies and maggots are of medical importance, and it is often necessary to identify them at species level. Conventionally, this is carried out based on morphological features using taxonomic keys. However, identification of maggots based on morphology is difficult and required entomological expertise is often lacking in clinical settings. Molecular methods can be an alternative to morphology-based identification and find special application when only tiny pieces of specimens are available especially in cases of human myiasis. In this preliminary study, we explored the utility of mitochondrial COI gene based molecular method, for identifying immature stages of certain medically important flies captured from the field in Puducherry, India. Maggots were captured from different locations in Puducherry using rotten fish and kitchen waste as baits and a 700 bp segment of the COI gene was amplified and genetic relationship was assessed by performing haplotype network analysis. High quality sequences were available for 11 specimens and were subjected to BLAST analysis to identify matches from the database for identification of the species. The identified maggots belonged to Sarcophaga peregrina (Robineau-Desvoidy, 1830), Hemipyrellia ligurriens (Wiedemann, 1830) and Chrysomya megacephala (Fabricius, 1794). This study generated representative molecular sequence data for two less studied fly species of medical importance, S. peregrina and H. ligurriens from South India. In future, there is a need for further detailed molecular studies on flies in the diverse epidemiological and geographic settings in India with a view to identify cryptic species and new haplotypes.

Identification of Diptera Puparia in Forensic and Archeo-Funerary Contexts

Diptera identification is fundamental in forensic entomology as well as in funerary archeoentomology, where the challenge is exacerbated by the presence of immature stages such as larvae and puparia. In these two developmental stages, specimens possess a very limited number of diagnostic features, and for puparia, there is also a lack of identification tools such as descriptions and identification keys. Morphological analysis, DNA-based techniques, and cuticular chemical analyses all show good potential for species identification; however, they also have some limitations. DNA-based identification is primarily hindered by the incompleteness of genetic databases and the presence of PCR inhibitors often co-extracted from the puparial cuticle. Chemical analysis of the cuticle is showing promising results, but this approach is also limited by the insufficient profile database and requires specific, expensive equipment, as well as trained personnel. Additionally, to ensure the repeatability of the analysis-a critical aspect in forensic investigations-and to preserve precious and unique specimens from museum collections, non-invasive protocols and techniques must be prioritized for species identification.

Age determination of Chrysomya megacephala (Diptera: Calliphoridae) using lifespan patterns, gene expression, and pteridine concentration under constant and variable temperatures

Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae), is a blowfly species widely studied in medical, veterinary, and entomological research. Our study examined the impact of constant (15, 20, 25, 30, and 35 °C) and variable (ranging from 21.0 to 25.4 °C, with an average of 23.31 °C) temperatures on the development and larval body length of C. megacephala. Additionally, we analyzed the age of the adult C. megacephala through pteridine content and related metabolic genes analysis. Our findings revealed three distinct growth patterns: isomorphen diagram, isomegalen diagram, and thermal accumulated models. At constant temperatures of 15, 20, 25, 30, and 35 °C, egg-hatching times were 44.5 ± 8.9, 26.7 ± 4.6, 12.6 ± 1.1, 11.0 ± 1.0, and 9.9 ± 1.9 h, respectively, while it was 15.3 ± 5.9 h at variable temperatures. The total development times from oviposition to adult eclosion in C. megacephala required 858.1 ± 69.2, 362.3 ± 5.9, 289.6 ± 17.8, 207.3 ± 9.3, and 184.7 ± 12.1 h at constant temperatures of 15, 20, 25, 30, and 35 °C, respectively. This duration was extended to 282.0 ± 64.1 h under variable temperatures. However, no significant differences were found in hatching times and the total developmental durations between 25 °C and variable temperatures. A developmental threshold temperature (D0) of 9.90 ± 0.77 °C and a thermal summation constant (K) of 4244.0 ± 347.0° hours were ascertained. Pteridine content patterns varied significantly across constant temperatures, but not between 25 °C and variable temperatures. Sex and temperature were identified as the primary factors influencing pteridine levels in the head of C. megacephala. Gene expression associated with pteridine metabolism decreased following adult eclosion, matching with increased pteridine concentration. Further investigations are needed to explore the use of pteridine cofactors for age-grading adult necrophagous flies. These findings provide valuable insights into the lifespan of C. megacephala, thereby offering valuable groundwork for forthcoming investigations and PMImin determination.

Geographical Distribution and Multimethod Species Identification of Forensically Important Necrophagous Flies on Hainan Island

Forensic entomology offers unique advantages for the minimum postmortem interval (PMImin) estimation of decomposed corpses in forensic investigations. Accurate species identification and up-to-date locality information are essential. Hainan Island has a tropical rainforest climate and a vast territory. In this study, the community structure of necrophagous flies on Hainan Island was investigated in detail according to geographical environment. The results showed that the dominant species included C. megacephala, S. peregrina, C. rufifacies, S. misera, H. ligurriens, S. sericea, S. cinerea, S. dux, C. pinguis, and M. domestica. Furthermore, C. rufifacies and C. villeneuvi were found only in the high-altitude areas of Wuzhi Mountain, while S. cinerea was distributed only in coastal areas; the latter is a representative species of Hainan Island and has not been reported before. Furthermore, a GenBank database of forensically important flies was established, whilst a high-resolution melt (HRM) curve analysis was applied to identify the common species of Hainan Island for the first time. This study enriches the database of forensically important flies in tropical rainforest regions.

Application of omics techniques in forensic entomology research

With the advent of the post-genome era, omics technologies have developed rapidly and are widely used, including in genomics, transcriptomics, proteomics, metabolomics, and microbiome research. These omics techniques are often based on comprehensive and systematic analysis of biological samples using high-throughput analysis methods and bioinformatics, to provide new insights into biological phenomena. Currently, omics techniques are gradually being applied to forensic entomology research and are useful in species identification, phylogenetics, screening for developmentally relevant differentially expressed genes, and the interpretation of behavioral characteristics of forensic-related species at the genetic level. These all provide valuable information for estimating the postmortem interval (PMI). This review mainly discusses the available omics techniques, summarizes the application of omics techniques in forensic entomology, and their future in the field.

A short fragment of mitochondrial DNA for the taxonomic identification of blow flies (Diptera: Calliphoridae) in northwestern South America

Blow flies are of medical, sanitary, veterinary, and forensic importance. Their accurate taxonomic identification is essential for their use in applied research. However, neotropical fauna has not been completely studied or described, and taxa identification without the required training is a difficult task. Additionally, the current morphological keys are not fitting to all extant taxa. Molecular-based approaches are widely used to overcome these issues, including the standard 5' COI barcode fragment (~650 base pairs [bp]) for identification at the species level. Here, a shorter sequence of 5' COI fragment (~342 bp) was assessed for the identification of 28 blow fly species inhabiting the northwest of South America. One tree-based (the generalized mixed Yule-coalescent-GMYC) and 3 distance-based approaches (automatic barcode gap discover - ABGD, the best close match - BCM, and the nearest neighbor - NN) analyses were performed. Noticeably, the amplification and sequencing of samples that had been preserved for up to 57 years were successful. The tree topology assigned 113 sequences to a specific taxon (70% effectiveness), while the distance approach assigned to 95 (59% effectiveness). The short fragment allowed the molecular identification of 19 species (60% of neotropical species except for the Lucilia species and Hemilucilia semidiaphana). According to these findings, the taxonomic and faunistic considerations of the blow fly fauna were provided. Overall, the short fragment approach constitutes an optimal species confirmation tool for the most common blow flies in northwestern South America.

Distinguishing Four Calliphoridae Species (Diptera) from Jamaica Using the Cephalopharyngeal Skeleton: Application to Forensic Investigations

Flies of the family Calliphoridae, commonly called blow flies, are important in the decomposition process. Knowledge on their succession pattern on corpses, species identification and the duration of their life cycle stages can be useful in forensic investigations especially when estimating the post-mortem interval. We performed linear-based morphometrics on the cephalopharyngeal skeleton of four blow fly species found in Jamaica to distinguish species and determine larval development stage. We collected eggs from pigs' heads used as bait in the field and conducted rearing exercises in the laboratory. We used the internal skeletonized structure, the cephalopharyngeal skeleton, to develop a practical and efficient method for species identification. For the first instar, we found species can be differentiated using all the measurements analysed in the study. We found that the mouth hook length may be useful in distinguishing larvae in the second instar. For the larvae in the third instar, the whole length of the skeleton, from mouth hook to length of the dorsal cornue, may be useful for separating species. We provide information on the cephalopharyngeal skeleton of Lucilia lucigerens (James), a blow fly species endemic to Jamaica, for the first time. Our work provides relevant information that could be utilized for species identification and life stage determination if fly evidence is to be incorporated in forensic investigations in Jamaica.

Species Delimitation of Scavenger Flies in the Valley of Mexico

Identification of species involved in cadaveric decomposition, such as scavenger Diptera, is a fundamental step for the use of entomological evidence in court. Identification based on morphology is widely used in forensic cases; however, taxonomic knowledge of scavenger fauna is poor for many groups and for many countries, particularly Neotropical ones. A number of studies have documented the utility of a DNA barcoding strategy to assist in the identification of poorly known and diverse groups, particularly in cases involving immature states or fragmented organisms. To provide baseline knowledge of the diversity of scavenger Diptera in the Valley of Mexico, we generated a DNA barcode collection comprised of sequences of the cytochrome c oxidase subunit 1 (COI) gene for all families sampled at a nature reserve located in this region. We collected and identified specimens on the basis of morphology and a species delimitation analysis. Our analyses of 339 individuals delineated 42 species distributed across nine families of Diptera. The richest families were Calliphoridae (9 species), Sarcophagidae (7 species), and Phoridae (6 species). We found many of the species previously recorded for the Valley of Mexico, plus 18 new records for the region. Our study highlights the utility of DNA barcoding as a first-step strategy to assess species richness of poorly studied scavenger fly taxa.

Characterizing Billbug (Sphenophorus spp.) Seasonal Biology Using DNA Barcodes and a Simple Morphometric Analysis

Simple Summary

Billbugs (Sphenophorus spp.) are a group of grass-feeding weevils considered to be one of the most important and widespread insect pests of turfgrass. However, our limited understanding of regional variation in billbug species composition and inability to identify the damaging larval stage to species level, has hindered our ability to resolve the seasonal biology of many billbug species and constrained development of effective management approaches. In this study, we developed a robust DNA barcoding approach for identification of morphologically cryptic billbug larvae. Using this molecular tool combined with larval head capsule measurements we characterized regional variation in billbug species and developed larval phenology charts. Our approach provides researchers with the molecular tools necessary to fill critical gaps in our understanding of billbug seasonal biology and will facilitate the development of improved turfgrass pest management programs.

Abstract

Billbugs (Sphenophorus spp.) are a complex of grass-feeding weevil species that reduce the aesthetic and functional qualities of turfgrass. Effective billbug monitoring and management programs rely on a clear understanding of their seasonal biology. However, our limited understanding of regional variation in the species compositions and seasonal biology of billbugs, stemming primarily from our inability to identify the damaging larval stage to species level, has hindered efforts to articulate efficient IPM strategies to growers. We used a combination of DNA barcoding methods and morphometric measures to begin filling critical gaps in our understanding of the seasonal biology of the billbug species complex across a broad geographic range. First, we developed a DNA barcoding reference library using cytochrome oxidase subunit 1 (COI) sequences from morphologically identified adult billbugs collected across Indiana, Missouri, Utah and Arizona. Next, we used our reference library for comparison and identification of unknown larval specimens collected across the growing season in Utah and Indiana. Finally, we combined our DNA barcoding approach with larval head capsule diameter, a proxy for developmental instar, to develop larval phenology charts. Adult COI sequences varied among billbug species, but variation was not influenced by geography, indicating that this locus alone was useful for resolving larval species identity. Overlaid with head capsule diameter data from specimens collected across the growing season, a better visualization of billbug species composition and seasonal biology emerged. This approach will provide researchers with the tools necessary to fill critical gaps in our understanding of billbug biology and facilitate the development of turfgrass pest management programs.

Characterization of New Molecular Markers of Three Botflies Parasitizing Cervid Hosts

Specific identification of oestrid larvae is usually problematic not only when using morphobiometric features, but also when applying molecular criteria, since very few molecular markers have been described for this group of flies. New molecular markers for oestrid are needed for more reliable species identification, diagnostic purposes, and epidemiological surveys; moreover, they can help in phylogenetic reconstruction. Here, we report the characterization of COI, 28S rDNA, ITS1, and ITS2 in Cephenemyia stimulator from roe deer and in Cephenemyia auribarbis and Pharyngomyia picta from red deer. The COI and 28S rDNA are very uniform in length, while the ITSs sequences are highly variable at both intraspecific and interspecific levels. The described ITSs sequences were longer than those described for other dipteran species by the presence of simple repeats and tandem repeat sequences. In C. auribarbis both ITS1 and ITS2 appeared as two variants, one short and the other long. In general, the analyzed markers present low intraspecific genetic variation and high interspecific variation. ITSs showed the greatest amount of intraspecific and interspecific variation. Phylogenetic analysis demonstrated that the characterized sequences differentiate the species and genera of Oestridae.

Cloacal myiasis by Lucilia spp. (Diptera: Calliphoridae) in a rooster (Gallus gallus domesticus) and two Harris's hawks (Parabuteo unicinctus)

In this study, cloacal myiasis caused by dipterans of Lucilia genus was found in a rooster (Gallus gallus domesticus) and two Harris's hawks (Parabuteo unicinctus) from Peru. Larval dipteran were collected and preserved in ethanol. Morphological analysis indicated two species: Lucilia sericata in the rooster and in one Harris's hawk, and Lucilia cuprina in the other Harris's hawk. Molecular analysis confirmed the diagnosis by amplification of the nucleotide sequences of the cytochrome c oxidase subunit 1 gene and internal transcribed spacer 2 region. The sequences were compared with sequence references from a public sequence database, which showed a 100% matched identity. This study demonstrated for first time cloacal myiasis by L. sericata in a domestic bird from Peru and in Harris's hawk. Also, for the first time, L. cuprina was found in a bird of prey.

The Forensic Entomology Case Report-A Global Perspective

Forensic practitioners analyzing entomological evidence are faced with numerous challenges when presenting their findings to law practitioners, particularly in terms of terminology used to describe insect age, what this means for colonization time of remains, and the limitations to estimates made. Due to varying legal requirements in different countries, there is no standard format for the entomological case report prepared, nor any guidelines as to the sections that are required, optional or unnecessary in a case report. The authors herein propose sections that should be considered when drafting an entomological case report. The criteria under which entomological evidence is analyzed are discussed, as well as the limitations for each criterion. The concept of a global, standardized entomological case report is impossible to achieve due to national legislative differences, but the authors here propose a basic template which can be adapted and changed according to the needs of the practitioner. Furthermore, while the discussion is fairly detailed, capturing all differences between nations could not be accomplished, and those initiating casework for the first time are encouraged to engage other practicing forensic entomologists or professional associations within their own nation or region, to ensure a complete report is generated that meets lab or national requirements, prior to generating a finalized report.

Testing the Accuracy of Vegetation-Based Ecoregions for Predicting the Species Composition of Blow Flies (Diptera: Calliphoridae)

To properly define ecoregions, specific criteria such as geology, climate, or species composition (e.g., the presence of endemic species) must be taken into account to understand distribution patterns and resolve ecological biogeography questions. Since the studies on insects in Baja California are scarce, and no fine-scale ecoregions based on the region's entomofauna is available, this study was designed to test whether the ecoregions based on vegetation can be used for insects, such as Calliphoridae. Nine collecting sites distributed along five ecoregions were selected, between latitudes 29.6° and 32.0°N. In each site, three baited traps were used to collect blow flies from August 2017 to June 2019 during summer, winter, and spring. A total of 30,307 individuals of blow flies distributed in six genera and 13 species were collected. The most abundant species were Cochliomyia macellaria (Fabricius), Phormia regina (Meigen), and Chrysomya rufifacies (Macquart). The composition of the Calliphoridae community was different between the localities and three general groups have been distinguished, based on the species composition similarity (ANOSIM) results: Gulf-Desert, Mountains, and Pacific-Center. The vegetation-based ecoregions only reflect the blow fly species' distributions to a certain extent, meaning that care must be taken when undertaking ecological biogeographical studies using regionalization based on organisms other than the focal taxa because vegetation does not always reflect fauna species composition.

Influence of montane altitudinal ranges on species distribution models; evidence in Andean blow flies

BACKGROUND

Blow flies are a family of dipterans of medical, veterinary and sanitary importance. We aim to predict the current geographical distribution of six neotropical blowfly species with different altitudinal ranges of distribution (high, medium, and lowlands) and degree of synanthropy (eusynanthropic, hemisynanthropic and asynanthropic) based on their existing fundamental niche (EA) in Northwestern South America.

METHODS

Geographical records were compiled based on data from museum specimens and literature. The accessible area hypothesis (M) was calculated based on three criteria: (1) Altitudinal range, (2) Synanthropy values deducted based on the Human Influence Index (HII) raster dataset, and (3). The mean dispersal capability of flies. The modeling was performed using the Maxent entropy modeling software. The selection of parameters was made with the R Program ENMeval package.

RESULTS

The models were assessed using the area under the operator-partial receiver curve (ROCp). The high statistical performance was evidenced in every modeling prediction. The modeling allowed identifying possible taxonomic inaccuracies and the lack of exhaustive collection in the field, especially for lowlands species. Geographical distribution predicted by the modeling and empirical data was remarkably coherent in montane species.

DISCUSSION

The data obtained evidence that montane elevational ranges affect the performance of the distribution models. These models will allow a more precise predicting of medium and high elevation blow flies than lowlands species. Montane species modeling will accurately predict the fly occurrence to use such biological information for medical, legal, veterinary, and conservation purposes.

Molecular identification of forensically important fly species in Spain using COI barcodes

Species identification with DNA barcodes has been proven to be effective on different organisms and, particularly, has become a routinely used and quite accurate tool in forensic entomology to study necrophagous Diptera species. In this study, we analysed 215 specimens belonging to 42 species of 17 genera, from 9 different Diptera families. Flies were collected in 39 Spanish localities of the Iberian Peninsula sampled across three years in the four seasons. Intraspecific variation ranged from 0 to 2.46% whereas interspecific variation fluctuated from 3.07 to 14.59%, measuring 651 pb of the cytochrome oxidase subunit one (COI) gene. Neighbour-Joining analysis was carried out to investigate the molecular identification capabilities of the barcoding region, recovering almost all species as distinct monophyletic groups. The species groupings were generally consistent with morphological and molecular identifications. This work, which is the first with this intensive and extensive sampling in this area, shows that the COI barcode is an appropriate marker for unambiguous identification of forensically important Diptera in Spain.

Ecological and geographical speciation in Lucilia bufonivora: The evolution of amphibian obligate parasitism

Lucilia (Diptera: Calliphoridae) is a genus of blowflies comprised largely of saprophagous and facultative parasites of livestock. Lucilia bufonivora, however, exhibits a unique form of obligate parasitism of amphibians, typically affecting wild hosts. The evolutionary route by which amphibian myiasis arose, however, is not well understood due to the low phylogenetic resolution in existing nuclear DNA phylogenies. Furthermore, the timing of when specificity for amphibian hosts arose in L. bufonivora is also unknown. In addition, this species was recently reported for the first time in North America (Canada) and, to date, no molecular studies have analysed the evolutionary relationships between individuals from Eastern and Western hemispheres. To provide broader insights into the evolution of the amphibian parasitic life history trait and to estimate when the trait first arose, a time-scaled phylogeny was inferred from a concatenated data set comprising mtDNA, nDNA and non-coding rDNA (COX1, per and ITS2 respectively). Specimens from Canada, the UK, Poland, Switzerland, the Netherlands and Germany were analysed, as well as individuals from its sister taxa, the saprophage Lucilia silvarum and a Nearctic species also implicated in amphibian myiasis, Lucilia elongata. Obligate amphibian parasitism appears to have arisen ~4 mya, likely as a result of niche displacement of a saprophagous/facultative parasite ancestor. Consistent paraphyly of L. bufonivora with respect to L. elongata across single-gene phylogenies and high mtDNA genetic distances between Nearctic and Palearctic individuals suggest on-going cryptic speciation facilitated by geographical isolation. These findings suggest that recent reports of L. bufonivora in the Nearctic do not constitute a recent introduction, but instead suggest that it remained unrecorded due to taxonomic confusion and low abundance. This is the first study to confirm the involvement of L. bufonivora in amphibian myiasis in Canada using DNA-based identification methods.

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Within Lucilia, a small genus of blowflies mostly comprised of carrion-breeding species, obligate parasitism for amphibians evolved around 4 mya.

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Geographic isolation between Nearctic and Palearctic lineages is facilitating on-going cryptic speciation of Lucilia bufonivora.

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First positive identification of L. bufonivora from two confirmed cases of amphibian myiasis in North America.

Eristalinus arvorum (Fabricius, 1787) (Diptera: Syrphidae) in Human Skull: A New Fly Species of Forensic Importance

A body of an unknown adult female was found within a shallow burial ground in Malaysia whereas the skull was exposed and visible on the ground. During autopsy examination, nine insect larvae were recovered from the interior of the human skull and subsequently preserved in 70% ethanol. The larvae were greyish in appearance, each with a posterior elongated breathing tube. A week after the autopsy, more larvae were collected at the burial site, and some of them were reared into adults. Adult specimens and larvae from the skull and from the burial site were sequenced to obtain DNA barcodes. Results showed all adult flies reared from the burial site, as well as the larvae collected from the skull were identified as Eristalinus arvorum (Fabricius, 1787) (Diptera: Syrphidae). Here, we report the colonization of E. arvorum larvae on a human corpse for the first time.

Do longer sequences improve the accuracy of identification of forensically important Calliphoridae species?

Species identification is a crucial step in forensic entomology. In several cases the calculation of the larval age allows the estimation of the minimum Post-Mortem Interval (mPMI). A correct identification of the species is the first step for a correct mPMI estimation. To overcome the difficulties due to the morphological identification especially of the immature stages, a molecular approach can be applied. However, difficulties in separation of closely related species are still an unsolved problem. Sequences of 4 different genes (COI, ND5, EF-1α, PER) of 13 different fly species collected during forensic experiments (Calliphora vicina, Calliphora vomitoria, Lucilia sericata, Lucilia illustris, Lucilia caesar, Chrysomya albiceps, Phormia regina, Cynomya mortuorum, Sarcophaga sp., Hydrotaea sp., Fannia scalaris, Piophila sp., Megaselia scalaris) were evaluated for their capability to identify correctly the species. Three concatenated sequences were obtained combining the four genes in order to verify if longer sequences increase the probability of a correct identification. The obtained results showed that this rule does not work for the species L. caesar and L. illustris. Future works on other DNA regions are suggested to solve this taxonomic issue.

Virus discovery in all three major lineages of terrestrial arthropods highlights the diversity of single-stranded DNA viruses associated with invertebrates

Viruses encoding a replication-associated protein (Rep) within a covalently closed, single-stranded (ss)DNA genome are among the smallest viruses known to infect eukaryotic organisms, including economically valuable agricultural crops and livestock. Although circular Rep-encoding ssDNA (CRESS DNA) viruses are a widespread group for which our knowledge is rapidly expanding, biased sampling toward vertebrates and land plants has limited our understanding of their diversity and evolution. Here, we screened terrestrial arthropods for CRESS DNA viruses and report the identification of 44 viral genomes and replicons associated with specimens representing all three major terrestrial arthropod lineages, namely Euchelicerata (spiders), Hexapoda (insects), and Myriapoda (millipedes). We identified virus genomes belonging to three established CRESS DNA viral families (Circoviridae, Genomoviridae, and Smacoviridae); however, over half of the arthropod-associated viral genomes are only distantly related to currently classified CRESS DNA viral sequences. Although members of viral and satellite families known to infect plants (Geminiviridae, Nanoviridae, Alphasatellitidae) were not identified in this study, these plant-infecting CRESS DNA viruses and replicons are transmitted by hemipterans. Therefore, members from six out of the seven established CRESS DNA viral families circulate among arthropods. Furthermore, a phylogenetic analysis of Reps, including endogenous viral sequences, reported to date from a wide array of organisms revealed that most of the known CRESS DNA viral diversity circulates among invertebrates. Our results highlight the vast and unexplored diversity of CRESS DNA viruses among invertebrates and parallel findings from RNA viral discovery efforts in undersampled taxa.

Integrative taxonomy of the genus Pseudostegana (Diptera, Drosophilidae) from China, with descriptions of eleven new species

The genus Pseudostegana (Okada, 1978) currently contains thirty-nine described species. A number of Pseudostegana were collected from the fieldwork in southwestern China from 2010 to 2017. Eleven new species were discovered and are described from southwestern China: Pseudostegana alpina Zhang & Chen, sp. nov.; Pseudostegana amnicola Zhang & Chen, sp. nov.; Pseudostegana amoena Zhang & Chen, sp. nov.; Pseudostegana mailangang Zhang & Chen, sp. nov.; Pseudostegana meiduo Zhang & Chen, sp. nov.; Pseudostegana meiji Zhang & Chen, sp. nov.; Pseudostegana mystica Zhang & Chen, sp. nov.; Pseudostegana stictiptrata Zhang & Chen, sp. nov.; Pseudostegana stigmatptera Zhang & Chen, sp. nov.; Pseudostegana ximalaya Zhang & Chen, sp. nov. and Pseudostegana zhuoma Zhang & Chen, sp. nov. A key to all Chinese Pseudostegana species based on morphological characters is provided. Two mitochondrial loci (COI and ND2) and one nuclear locus (28S rRNA) were sequenced for the Pseudostegana specimens, and Bayesian and RAxML concatenated analyses were run. Molecular species delimitation is performed using the distance-based automatic barcode gap discovery (ABGD) method. Molecular data support the morphological characteristics observed among these Chinese species and confirm the new species as being distinctly different.

New Distribution Record for Lucilia cuprina (Diptera: Calliphoridae) in Indiana, United States

Determining range expansion for insect species is vital in order to evaluate their impact on new ecosystems and communities. This is particularly important for species which could be potentially harmful to humans or domestic animals. Lucilia cuprina Wiedemann (Diptera: Calliphoridae) can act as a facultative ectoparasite and has an extensive history as the primary inducer of sheep-strike in Australia, New Zealand, and Africa. We present here the first record of this species in Indiana, United States. Lucilia cuprina's range expansion northward in the United States may be indicative of changing environmental conditions conducive to the proliferation of this species into historically cooler climates. The presence of this species could significantly impact forensic death investigations utilizing dipteran larvae to estimate a minimum postmortem interval. If range expansion of this species is not taken into account by a forensic entomologist (especially if L. cuprina is not known previously in their region), an inaccurate minimum postmortem interval (PMIMIN) estimation may be made, given the differences in development times for both species. Therefore, the range expansion of this fly could have large impacts for many different entomological disciplines.

DNA Barcodes for Forensically Important Fly Species in Brazil

Here, we analyze 248 DNA barcode sequences of 35 fly species of forensic importance in Brazil. DNA barcoding can be effectively used for specimen identification of these species, allowing the unambiguous identification of 31 species, an overall success rate of 88%. Our results show a high rate of success for molecular identification using DNA barcoding sequences and open new perspectives for immature species identification, a subject on which limited forensic investigations exist in Tropical regions. We also address the implications of building a robust forensic DNA barcode database. A geographic bias is recognized for the COI dataset available for forensically important fly species in Brazil, with concentration of sequences from specimens collected mainly in sites located in the Cerrado, Mata Atlântica, and Pampa biomes.