Molecular identification of forensically important beetles in Saudi Arabia based on mitochondrial 16 s rRNA gene

Forensic science uses scientific methods to help the scientists who study evidence to assist in the solving of crimes. Coleoptera is the most diverse and speciose group of insects that have an important role in many scientific fields especially forensic entomology. In addition, it is difficult to morphologically identify and discriminate between them. In the present study, the molecular analysis using mitochondrial DNA information was conducted to swiftly and accurately identify the recovered Coleoptera species. A molecular identification method involving a 221‐bp segment of the 16 s ribosomal RNA (16 s rRNA) gene from three beetle species, collected from a rabbit carcass, was evaluated. The analysis with maximum likelihood method recovered a generally well supported phylogeny, with most currently accepted taxa and species groups as monophyletic. These results will be instrumental for the implementation of the Saudian database of forensically relevant beetles.     

Impacts of antemortem ingestion of alcoholic beverages on insect successional patterns

This paper studies the impacts of antemortem ingestion of alcoholic beverages by the domestic rabbit, Oryctolagus cuniculus L., on postmortem successional patterns of insects during winter and summer 2018 in Riyadh, Saudi Arabia. Insect samples were collected from the carcasses of rabbits fed alcoholic beverages as well as untreated rabbits for 15 days postmortem during two successional studies in each season. The results showed that, during both seasons, the decomposition process for the carcasses of rabbits fed alcoholic beverages antemortem was one to two days longer. The results also showed, however, that alcoholic beverages did not affect insect succession patterns in either season. In fact, the number of insects appeared to be influenced by the ambient temperature during the two seasons, with 4415 insects in the winter compared to 1033 insects in the summer. In total, 30 insect taxa were collected during the winter study from the carcasses of rabbits fed alcoholic beverages antemortem; while 26 of these same taxa were collected from the carcasses of the untreated rabbits. Among the treated rabbits, those fed 25 ml alcoholic beverages treated attracted the highest number of insect taxa (24 taxa). In the summer study, 21 insect taxa were collected in total, 19 from the carcasses of the alcohol-treated rabbits and 13 from untreated rabbits. Among the treated rabbits, those fed 50 ml alcoholic beverages attracted the highest number of insect taxa (14 taxa). These results contribute to the understanding of the factors affecting the use of insects in medical investigations, given that alcoholic beverages are a common addictive agent.     

Accumulation and excretion of morphine by Calliphora stygia, an Australian blow fly species of forensic importance

This study examined the ability of the forensically important blow fly, Calliphora stygia to actively excrete morphine, thereby maintaining a low morphine level within its body when fed on a diet containing morphine at low (7 pmol g⁻¹) and high (17.5 pmol g⁻¹) concentrations. Morphine was accumulated within the bodies of maggots (≈70% within the tissues) at concentrations which were lower than that of the meat (3-24%). The morphine content of the initial developing stages (second and third instar maggots) maintained on the high morphine diet was higher than those on the low morphine diet. Morphine was cleared from the body with negatively exponential kinetics (High morphine group: Morphine (pmol g⁻¹ wet weight) = 8425e^−0.014t. Low morphine group: Morphine (pmol g⁻¹ wet weight) = 2180e^−0.010t). Clearance constants for morphine by animals in both groups were similar and thus both groups had a similar ability to excrete morphine. The Malpighian tubules of maggots were able to actively secrete morphine using a transport mechanism that transports small type II organic cations, such as morphine and quinine. The rate of morphine secretion by the Malpighian tubules could explain the clearance of the drug by the maggots. As the morphine was transported across the Malpighian tubules cells, a significant proportion was metabolised into a compound that is yet to be fully characterised.     

Molecular phylogeny of the blowfly genus Chrysomya

Chrysomya Robineau-Desvoidy (Diptera: Calliphoridae) is a genus of blowfly commonly observed in tropical and subtropical countries of the Old World. Species in this genus are vectors of bacteria, protozoans and helminths, cause myiasis, are predators of other carrion insects, and are important forensic indicators. Hypotheses concerning the evolution of sex determination, larval anatomy and genome size in Chrysomya have been difficult to evaluate because a robust phylogeny of the genus was lacking. Similarly, the monophyly of subgenera was uncertain. The phylogeny of Chrysomya spp. was reconstructed based on 2386 bp of combined mitochondrial cytochrome oxidase subunit I (COI) and nuclear carbamoylphosphate synthetase (CPS) genes. Maximum parsimony (MP), maximum likelihood (ML) and Bayesian analysis (BA) differed only slightly in the resulting tree topology. Chrysomya was monophyletic. Monogenic reproduction is almost certainly derived rather than, as has been suggested, primitive within the genus, and tuberculate larvae probably evolved twice. Genome size is more likely to have decreased over evolutionary time rather than, as has been suggested, increased within the genus, but its correlation with developmental time was not observed. The subgenera Microcalliphora, Eucompsomyia and Achoetandrus were recovered as monophyletic.     

Linnaeus's butterflies (Lepidoptera: Papilionoidea and Hesperioidea)

The names of all the species of butterflies described by Linnaeus under "Papilio" are researched. Of the 305 names treated, 243 (c. 80%) are currently valid as specific (241) or subspecific (2), 29 are junior synonyms, 14 are invalid (one of these applying to a fake), and for 13 the identity is unknown or uncertain. Six species of moths misidentified by Linnaeus as butterflies are cited in the study, but details are not included. One hundred and fifty-two lectotypes have been designated, representing about 56% of the sum of the valid names and junior synonyms. Of these, 99 were selected from specimens in the Linnean Society of London, 52 from Queen Ludovica Ulrica's collection, Uppsala, and one lectotype is a Petiver specimen from the collection of Sir Hans Sloane. Linnaeus described at least five species, possibly eight, from the literature alone. All Linnaean material examined is documented, as are 'subsequent' specimens that are associated with Linnaean material. Synonymy and homonymy are discussed and presented, as are the identities of type localities. Care has been taken to achieve a practical balance between Linnaean and current species identities. Linnaean material studied included specimens from The Linnean Society of London, Museum Ludovicae Ulricae (Uppsala University), the Clerck and De Geer collections in the Naturhistoriska Riksmuseet, Stockholm, and the collection of James Petiver, now part of the collection of Sir Hans Sloane housed in The Natural History Museum, London.     

Identification of forensically important flesh flies based on a shorter fragment of the cytochrome oxidase subunit I gene in China

With the development of molecular identification, there has been a great deal of discussion about the feature of the mitochondrial DNA (mtDNA) fragments. Although longer fragments may minimize stochastic variation across taxa and be more likely to reflect broader patterns of nucleotide divergence, shorter fragments have many advantages, such as quick, easy and economical. Extensive application of long mtDNA segments for species identification cannot always be achieved as a result of constraints in time and money. In the present study, a molecular identification method involving the sequencing of a 272-bp 'barcode' fragment of the mitochondrial cytochrome oxidase subunit I (COI) gene from 55 specimens, representing 7 Chinese sarcophagid species from varying populations, was evaluated. Phylogenetic analysis of the sequenced segments showed that all sarcophagid specimens were properly assigned into seven species, which indicated the possibility of separation congeneric species with the short fragments. The results of this research will be instrumental for the implementation of the Chinese Sarcophagidae database.     

STRUCTURE AND DEVELOPMENT OF EMBRYOS OF EPHESTIA CAUTELLA (WALKER) DURING ANOXIA AND PHOSPHINE TREATMENT

Exposure of Ephestia cautella eggs to anoxic conditions retards the development of the embryo, causing a marked delay in hatching. Phosphine treatment results in little or no hatch delay in surviving embryos and produces characteristic ultrastructural lesions, mainly manifested as changes in mitochondrial organization.     

The upper thermal tolerance for a Texas population of the hairy maggot blow fly Chrysomya rufifacies Macquart (Diptera: Calliphoridae)

1. The hairy maggot blow fly (Chrysomya rufifacies: Macquart) is an invasive necrophagous fly found throughout the continental United States. Chrysomya rufifacies is of medical/veterinary, forensic, and ecological importance due to its ability to cause myiasis, colonise human remains, and displace native Diptera. However, little is known about their upper thermal tolerance, which could be used to better predict their invasion potential.
2. We investigated the upper thermal tolerance of C. rufifacies exposed to different temperatures (20–45 °C), times (1–6 h), and nutrients (no food or water, water only, or a food-water mixture) for both sexes and two age ranges (young = 6–8 days post pupal emergence; old = 9–11 days post pupal emergence).
3. As temperature or duration increased, the probability of knockdown increased (0–100% at 20 and 45 °C and from 41 to 75% at 1 and 6 h), while the probability of survival decreased (99–2% at 20 and 45 °C and from 75 to 28% at 1 and 6 h). The availability of nutrients increased thermal tolerance at moderate temperatures (40 and 42 °C). Female flies were more thermally tolerant than males (probability of knockdown = 49% vs 58%; probability of survival = 58% vs 46%). Thermal tolerance did not differ by age.
4. These data reveal details about the upper thermal tolerance for a single population of C. rufifacies, and suggest that environmental and organismal factors ought to be considered in order to make meaningful predictions about the invasion potential of C. rufifacies in North America.

     

垂直监测昆虫雷达研究进展

昆虫雷达可以远距离、 大范围、 快速地探测迁飞昆虫, 这极大促进了人类对昆虫迁飞行为的认识。垂直监测昆虫雷达技术是从20世纪70年代发展起来的一种监测高空迁飞昆虫种群的新工具。与传统的扫描雷达相比, 垂直监测昆虫雷达可以获得目标的位移速度、 位移方向、 定向、 体型大小和形状等参数, 因此, 对目标的识别能力更为精确。此外, 垂直监测昆虫雷达实现了在微机控制下的自动运行, 这使得应用昆虫雷达开展迁飞昆虫的日常监测成为可能。本文综述了垂直监测昆虫雷达的发展和应用, 介绍了设计原理和回波参数的解算方法, 讨论了其存在的不足及改进方案, 最后并对其在未来昆虫雷达网络建设中的应用进行了展望。