Carrion beetles of genus Thanatophilus (Leach, 1815) are an important group of necrophagous insects, with great potential for forensic entomology in temperate zones of Africa, America, Asia, and Europe. Developmental models for majority of Thanatophilus species remain unknown. In this study, we will provide new thermal summation models for all the developmental stages of Thanatophilus sinuatus (Fabricius, 1775), one of the most abundant and widespread species of the genus. The beetles were bred at seven different constant temperatures, and developmental time was measured for each developmental stage (egg, three larval instars, postfeeding stage, and pupa). Temperature-sex influence was tested, and thermal summation constants were calculated to be used for postmortem interval estimation during criminal investigations.

• MeSH
• biologické modely MeSH
• brouci růst a vývoj   MeSH
• forenzní entomologie * MeSH
• kukla růst a vývoj   MeSH
• larva růst a vývoj   MeSH
• ovum růst a vývoj   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The postmortem interval (PMI) estimation, in cases where the body was discovered in an advanced stage of decomposition, is predominantly based on entomological evidence. However, very few forensically important species are sufficiently known in detail to allow a practical application. One of them is the carrion beetle, Necrophila (Calosilpha) brunnicollis (Kraatz, 1877). Its development from egg to adulthood was studied under a range of ecologically relevant constant temperatures to find parameters of thermal summation models. Developmental sexual dimorphism and the presence of developmental rate isomorphy were investigated. Herein we present the lower developmental thresholds and sum of effective temperatures for all developmental stages of N. brunnicollis (egg, first-third larval instar, postfeeding stage, and pupae). We did not find any evidence of developmental sexual dimorphism nor was the presence of developmental rate isomorphy confirmed. Our results present the first thermal summation model of the East Asian carrion beetle that can be used for the PMI estimation.

• MeSH
• brouci růst a vývoj   MeSH
• forenzní entomologie metody   MeSH
• kukla růst a vývoj   MeSH
• larva růst a vývoj   MeSH
• mrtvola MeSH
• posmrtné změny MeSH
• sexuální faktory MeSH
• teoretické modely MeSH
• teplota MeSH
• zvířata MeSH
• zvláštnosti životní historie MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Carlina acaulis (Compositae) is traditionally used for food and medicinal purposes in central and southern Europe. Its root essential oil (EO), mainly composed by carlina oxide, is included in the BELFRIT botanical list of food supplements. It is also recognized as a potent mosquito larvicide. It is matter of concern whether this EO could be endowed with intrinsic toxicity to limit its use on a food level. Focusing on the insecticidal activity of this EO, we investigated the acute toxicity and sublethal effects on Musca domestica. In topical assays, the EO was extremely effective (LD50 = 2.74 and 5.96 μg fly-1, on males and females, respectively). The exposure to a sublethal dose (LD30) led to significant reductions of female longevity (LT50 = 6.7-9.0 days vs. control LT50 = 12.9-13.7 days). Treated females laid 2.5 times fewer eggs over control ones. F1 vitality decreased: F1 larvae and pupae showed high mortality, 2-4-fold higher over the control. The EO also showed high cytotoxicity on normal human fibroblasts (NHF-A12, IC50 = 9.4-14.2 μg mL-1 after 6-48 h). Overall, our findings support the employ of this EO for developing botanical insecticides. At the same time, they encourage food safety authorities to perform a full toxicological assessment for possible restrictions at food level.

• MeSH
• buněčné linie MeSH
• insekticidy toxicita   MeSH
• kořeny rostlin chemie   MeSH
• kukla účinky léků   MeSH
• larva účinky léků   MeSH
• lidé MeSH
• Magnoliopsida chemie   MeSH
• moucha domácí účinky léků   MeSH
• oleje prchavé toxicita   MeSH
• oleje rostlin toxicita   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Neonicotinoid insecticides are associated with a decline in the diversity and distribution of bees and wasps (Hymenoptera: Aculeata). The effects of neonicotinoids on the metamorphosis of aculeates have never been addressed in detail; however, recent evidence suggests that neonicotinoids induce wing abnormalities. We hypothesized that the metamorphosis success of bees and wasps differs in response to contact exposure to field-realistic concentrations of neonicotinoid insecticides or in response to combined exposure to neonicotinoid insecticides and benzimidazole fungicides. We treated prepupae of the model crabronid wasp Pemphredon fabricii with field-realistic concentrations of four neonicotinoids, acetamiprid, imidacloprid, thiacloprid and thiamethoxam, and/or with the benzimidazole fungicide thiabendazole. Treatment with acetamiprid or imidacloprid decreased the pupation rates to only 39% and 32%, respectively. Treatment with thiacloprid or thiamethoxam did not affect the pupation rate when applied alone, but the subsequent treatment of thiacloprid- or thiamethoxam-treated prepupae with thiabendazole led to significant decreases in pupation rates. A high concentration of acetamiprid, which severely affected the pupation rates, had moderate effects on metamorphosis into adults, resulting in 53% metamorphosis success (as opposed to 95% metamorphosis success in the water-treated group). However, imidacloprid or thiamethoxam treatment resulted in only 5%-10% metamorphosis success into adults. Overall survival decreased in response to treatment with any of the neonicotinoids or benzimidazoles or their combinations, with extremely low survival (<2%) following combined treatment with imidacloprid and thiabendazole or thiamethoxam and thiabendazole. In conclusion, neonicotinoids alter insect metamorphosis success, which can be further potentiated by their combination with other agrochemicals, such as benzimidazoles.

• MeSH
• biologická proměna účinky léků   MeSH
• insekticidy farmakologie   MeSH
• kukla růst a vývoj   MeSH
• neonikotinoidy farmakologie   MeSH
• sršňovití růst a vývoj   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Juvenile hormones (JHs) are sesquiterpenoids synthesized by the corpora allata (CA). They play critical roles during insect development and reproduction. The first JH was described in 1934 as a "metamorphosis inhibitory hormone" in Rhodnius prolixus by Sir Vincent B. Wigglesworth. Remarkably, in spite of the importance of R. prolixus as vectors of Chagas disease and model organisms in insect physiology, the original JH that Wigglesworth described for the kissing-bug R. prolixus remained unidentified. We employed liquid chromatography mass spectrometry to search for the JH homologs present in the hemolymph of fourth instar nymphs of R. prolixus. Wigglesworth's original JH is the JH III skipped bisepoxide (JHSB3), a homolog identified in other heteropteran species. Changes in the titer of JHSB3 were studied during the 10-day long molting cycle of 4th instar nymph, between a blood meal and the ecdysis to 5th instar. In addition we measured the changes of mRNA levels in the CA for the 13 enzymes of the JH biosynthetic pathway during the molting cycle of 4th instar. Almost 90 years after the first descriptions of the role of JH in insects, this study finally reveals that the specific JH homolog responsible for Wigglesworth's original observations is JHSB3.

• MeSH
• biologická proměna * MeSH
• corpora allata chemie   MeSH
• epoxidové sloučeniny chemie   MeSH
• hemolymfa chemie   MeSH
• kukla chemie   fyziologie   MeSH
• nymfa chemie   fyziologie   MeSH
• Rhodnius chemie   fyziologie   MeSH
• seskviterpeny chemie   MeSH
• shazování tělního pokryvu fyziologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

The late 5th instar caterpillar of the cecropia silk moth (Hyalophora cecropia) spins a silken cocoon with a distinct, multilayered architecture. The cocoon construction program, first described by the seminal work of Van der Kloot and Williams, consists of a highly ordered sequence of events. We perform behavioral experiments to re-evaluate the original cecropia work, which hypothesized that the length of silk that passes through the spinneret controls the orderly execution of each of the discrete events of cocoon spinning. We confirm and extend by three-dimensional scanning and quantitative measurements of silk weights that if cocoon construction is interrupted, upon re-spinning, the caterpillar continues the cocoon program from where it left off. We also confirm and extend by quantitative measurements of silk weights that cecropia caterpillars will not bypass any of the sections of the cocoon during the construction process, even if presented with a pre-spun section of a cocoon spun by another caterpillar. Blocking silk output inhibits caterpillars from performing normal spinning behaviors used for cocoon construction. Surprisingly, unblocking silk output 24-hr later did not restart the cocoon construction program, suggesting the involvement of a temporally-defined interval timer. We confirm with surgical reductions of the silk glands that it is the length of silk itself that matters, rather than the total amount of silk extracted by individuals. We used scanning electron microscopy to directly show that either mono- or dual-filament silk (i.e., equal silk lengths but which vary in their total amount of silk extracted) can be used to construct equivalent cocoons of normal size and that contain the relevant layers. We propose that our findings, taken together with the results of prior studies, strongly support the hypothesis that the caterpillar uses a silk "odometer" to measure the length of silk extracted during cocoon construction but does so in a temporally regulated manner. We further postulate that our examination of the anatomy of the silk spinning apparatus and ablating spinneret sensory output provides evidence that silk length measurement occurs upstream of output from the spinneret.

• MeSH
• biobehaviorální přístup MeSH
• biologická proměna fyziologie   MeSH
• bourec anatomie a histologie   fyziologie   MeSH
• chování zvířat fyziologie   MeSH
• čití, cítění fyziologie   MeSH
• hedvábí analýza   chemie   metabolismus   MeSH
• kukla fyziologie   MeSH
• Manduca anatomie a histologie   fyziologie   MeSH
• mikroskopie elektronová rastrovací MeSH
• senzorická zpětná vazba fyziologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

An animal's fitness strongly depends on successful feeding, avoidance of predators and reproduction. All of these behaviours commonly involve chemosensation. As a consequence, when species' ecological niches and life histories differ, their chemosensory abilities need to be adapted accordingly. The intertidal insect Clunio marinus (Diptera: Chironomidae) has tuned its olfactory system to two highly divergent niches. The long-lived larvae forage in a marine environment. During the few hours of terrestrial adult life, males have to find the female pupae floating on the water surface, free the cryptic females from their pupal skin, copulate and carry the females to the oviposition sites. In order to explore the possibility for divergent olfactory adaptations within the same species, we investigated the chemosensory system of C. marinus larvae, adult males and adult females at the morphological and molecular level. The larvae have a well-developed olfactory system, but olfactory gene expression only partially overlaps with that of adults, likely reflecting their marine vs. terrestrial lifestyles. The olfactory system of the short-lived adults is simple, displaying no glomeruli in the antennal lobes. There is strong sexual dimorphism, the female olfactory system being particularly reduced in terms of number of antennal annuli and sensilla, olfactory brain centre size and gene expression. We found hints for a pheromone detection system in males, including large trichoid sensilla and expression of specific olfactory receptors and odorant binding proteins. Taken together, this makes C. marinus an excellent model to study within-species evolution and adaptation of chemosensory systems.

• MeSH
• biologická adaptace fyziologie   MeSH
• bulbus olfactorius metabolismus   fyziologie   MeSH
• Chironomidae metabolismus   fyziologie   MeSH
• čich fyziologie   MeSH
• čichové buňky metabolismus   MeSH
• hmyz metabolismus   fyziologie   MeSH
• hmyzí proteiny metabolismus   MeSH
• kladení vajíček fyziologie   MeSH
• kukla metabolismus   fyziologie   MeSH
• larva metabolismus   MeSH
• pohlavní dimorfismus * MeSH
• receptory pachové metabolismus   MeSH
• sensilla metabolismus   fyziologie   MeSH
• vodní organismy metabolismus   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Insect metamorphosis boasts spectacular cases of postembryonic development when juveniles undergo massive morphogenesis before attaining the adult form and function; in moths or flies the larvae do not even remotely resemble their adult parents. A selective advantage of complete metamorphosis (holometaboly) is that within one species the two forms with different lifestyles can exploit diverse habitats. It was the environmental adaptation and specialization of larvae, primarily the delay and internalization of wing development, that eventually required an intermediate stage that we call a pupa. It is a long-held and parsimonious hypothesis that the holometabolous pupa evolved through modification of a final juvenile stage of an ancestor developing through incomplete metamorphosis (hemimetaboly). Alternative hypotheses see the pupa as an equivalent of all hemimetabolous moulting cycles (instars) collapsed into one, and consider any preceding holometabolous larval instars free-living embryos stalled in development. Discoveries on juvenile hormone signalling that controls metamorphosis grant new support to the former hypothesis deriving the pupa from a final pre-adult stage. The timing of expression of genes that repress and promote adult development downstream of hormonal signals supports homology between postembryonic stages of hemimetabolous and holometabolous insects. This article is part of the theme issue 'The evolution of complete metamorphosis'.

• MeSH
• biologická proměna * MeSH
• hmyz klasifikace   růst a vývoj   MeSH
• juvenilní hormony metabolismus   MeSH
• kukla růst a vývoj   MeSH
• signální transdukce * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Knowledge of microbiota composition, persistence, and transmission as well as the overall function of the bacterial community is important and may be linked to honey bee health. This study aimed to investigate the inter-individual variation in the gut microbiota in honey bee larvae and pupae. RESULTS: Individual larvae differed in the composition of major bacterial groups. In the majority of 5th instar bees, Firmicutes showed predominance (70%); however, after larval defecation and during pupation, the abundance decreased to 40%, in favour of Gammaproteobacteria. The 5th instar larvae hosted significantly more (P < 0.001) Firmicutes than black pupae. Power calculations revealed that 11 and 18 replicate-individuals, respectively, were required for the detection of significant differences (P < 0.05) in the Bacteroidetes and Firmicutes abundance between stages, while higher numbers of replicates were required for Actinobacteria (478 replicates) and Gammaproteobacteria (111 replicates). CONCLUSIONS: Although sample processing and extraction protocols may have had a significant influence, sampling is very important for studying the bee microbiome, and the importance of the number of individuals pooled in samples used for microbiome studies should not be underestimated.

• MeSH
• Bacteria klasifikace   genetika   izolace a purifikace   MeSH
• časové faktory MeSH
• fylogeneze MeSH
• kladení vajíček * MeSH
• kukla anatomie a histologie   mikrobiologie   MeSH
• larva anatomie a histologie   mikrobiologie   MeSH
• mikrobiota MeSH
• RNA ribozomální 16S genetika   MeSH
• sekvenční analýza DNA metody   MeSH
• střevní mikroflóra MeSH
• včely anatomie a histologie   mikrobiologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Necrophagous beetles of genus Thanatophilus are well recognized as a group of beetles with a high potential utility in forensic entomology. They can be used to estimate postmortem interval (PMI) or validate the value for other groups of insects commonly encountered on human remains, like blowflies (Calliphoridae). However, reliable tools for instar and species identification of their larvae are needed as such information is crucial for allowing accurate PMI estimate. One of the most common species of the genus Thanatophilus in Europe is Thanatophilus sinuatus. This species occurs frequently on human remains and its larvae feed on decaying tissues throughout their development. Therefore, the larvae could become useful bioindicators for forensic entomology, although their current description does not allow reliable instar or species identification. Our goal was to provide morphological characters for species and instar identification of all larval stages of T. sinuatus. The larvae were obtained from laboratory rearing under controlled conditions (20 °C and 16:8 h of light/dark period). Qualitative and quantitative morphological instar and species-specific characters are described and illustrated. Additionally, we report observations of biological and developmental lengths for all stages of the species. We also compared these morphological characters with recent description of T. rugosus and provided an identification key of these two similar and often co-occurring species. We noticed that some characters for instar identification were shared between T. sinuatus and T. rugosus and were confirmed by comparison with larvae of T. dentigerus that they can be applied to other species of the genus.

• MeSH
• brouci klasifikace   růst a vývoj   MeSH
• forenzní entomologie * MeSH
• hodnotící studie jako téma MeSH
• kukla klasifikace   růst a vývoj   MeSH
• larva klasifikace   růst a vývoj   MeSH
• mikroskopie elektronová rastrovací MeSH
• optické zobrazování MeSH
• stravovací zvyklosti MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH