Effects of Different Doses of Gamma Rays on The Dispersal and Flight Ability Index of Mediterranean Fruit Fly Ceratitis Capitata (Wiedmann) (Diptera: Tephritidae)

This investigation concentrated on studying the effect of gamma rays on the flight ability index and on the dispersal of irradiated males because these two parameters were very important for applying the sterile male release technique. The results of this study showed that the flight ability index of irradiated males as pupae of 3, 4 and 5 days with doses ranged from 60 to 120 Gy were highly significant p<0.05 compared with control treatment during an experiment carried out under field conditions. The results showed that there were a reverse relationship between flight ability index and gamma rays doses. Furthermore, the results of this investigation also showed that there were a reverse relationship between the mean average of males captured by the pheromone traps and gamma rays doses after 1,2,3, and 4 days from the release.

Hypoxia combined with chilling maintains the quality of irradiated Drosophila flies: a simulated shipment experiment

Drosophila suzukii is an invasive fruit pest in Europe and America. Females lay eggs into mature fruit that larvae consume causing important losses. Sterile insect technique (SIT) is under development to control this pest. The efficiency of this technique relies on insect quality. However, during the process from mass production to field release, several steps may compromise insect quality and therefore SIT success. Shipment of sterile insects after irradiation is a key step of SIT programmes. Generally, insects are shipped as pupae and conditions during transport need to be adapted to prevent emergence before field release, while guaranteeing insect quality. To do so, transport is usually performed under low temperature, hypoxia or a combination of both. However, the impact of multiple stressors such as irradiation followed by chilling combined with hypoxia is poorly described and has not been studied in D. suzukii. Therefore, the aim of this study was to simulate a shipment of D. suzukii pupae (irradiated or not) under different conditions (chilling combined or not with hypoxia) for various durations, and to assess consequences on emerged adults. Irradiation followed by hypoxia and/or chilling only weakly altered emergence. However, 48 h of hypoxia without chilling altered the flight ability of flies whether or not they were irradiated. Conversely, when hypoxia was combined with chilling, flight ability remained similar to that of untreated flies. The use of chilling in combination with hypoxia for 48 h could be implemented as a transportation method for SIT programme on D. suzukii.

Tropilaelaps mercedesae parasitism changes behavior and gene expression in honey bee workers

Tropilaelaps mercedesae is one of the most problematic honey bee parasites and has become more threatening to the beekeeping industry. Tropilaelaps can easily parasitize immature honey bees (larvae and pupae) and have both lethal and sublethal effects on the individual worker bees. Our study for the first time experimentally assessed the effects of T. mercedesae on olfactory learning, flight ability, homing ability as well as transcriptional changes in parasitized adult honey bees. T. mercedesae infestation had negative impacts on olfactory associated function, flight ability, and homing rate. The volume of the mushroom body significantly increased in infested honey bees, which may be correlated to the lower sucrose responsiveness as well as lower learning ability in the infested bees. The gene expression involved in immune systems and carbohydrate transport and metabolism were significantly different between infested bees and non-infested bees. Moreover, genes function in cell adhesion play an essential role in olfactory sensory in honey bees. Our findings provide a comprehensive understanding of European honey bees in response to T. mercedesae infestation, and could be used to further investigate the complex molecular mechanisms in honey bees under parasitic stress.

Galápagos Derailed

The same species of Galápagos rail, a 6-inch insectivorous ground bird, has been reported on all eight islands with a highland humid zone. Evidence suggests that the rail colonized Galápagos at roughly the same time as giant tortoises, which evolved into 15 species with life spans of 150 years. So why is there just one species of rail? The question is especially germane given reports of the rail’s “reduced flight ability” (as is true of many island-dwelling rails), which would effectively isolate different island populations. And why has the species survived when so many similar rails have succumbed to human influence on other Pacific islands? The human history of Galápagos helps to answer these questions. Two things have saved the Galápagos rail from extinction: (1) It remains capable of flying between islands, which explains why it failed to differentiate like tortoises. (2) There have been massive efforts to eradicate or control invasive species, restoring habitat for rails to repopulate.

De novo transcriptome analysis for examination of the nutrition metabolic system related to the evolutionary process through which stick insects gain the ability of flight (Phasmatodea)

Objective Insects are the most evolutionarily successful groups of organisms, and this success is largely due to their flight ability. Interestingly, some stick insects have lost their flight ability despite having wings. To elucidate the shift from wingless to flying forms during insect evolution, we compared the nutritional metabolism system among flight-winged, flightless-winged, and flightless-wingless stick insect groups. Results Here, we report RNA sequencing of midgut transcriptome of Entoria okinawaensis, a prominent Japanese flightless-wingless stick insect, and the comparative analysis of its transcriptome in publicly available midgut transcriptomes obtained from seven stick insect species. A gene enrichment analysis for differentially expressed genes, including those obtained from winged vs wingless and flight vs flightless genes comparisons, revealed that carbohydrate metabolic process-related genes were highly expressed in the winged stick insect group. We also found that the expression of the mitochondrial enolase superfamily member 1 transcript was significantly higher in the winged stick insect group than in the wingless stick insect group. Our findings could indicate that carbohydrate metabolic processes are related to the evolutionary process through which stick insects gain the ability of flight.

Revision of the intertidal rove beetle genus Bryothinusa from Japan (Coleoptera: Staphylinidae: Aleocharinae)

The Japanese species of the intertidal rove beetle genus Bryothinusa Casey, 1904 are revised. Of 17 recognized species in total, six known species (B. algarum Sawada, 1971, B. gangjinensis Ahn & Jeon, 2004, B. minuta (Sawada, 1955), B. nakanei (Sawada, 1955), B. sakishimana Sawada, 1991, B. tsutsuii (Sawada, 1955)) are redescribed and nine new species (B. aikoae sp. nov. from Honshû, B. constricta sp. nov. from Honshû, B. fulvipennis sp. nov. from Honshû and Shikoku, B. hokkaidensis sp. nov. from Hokkaidô and Kyûshû, B. itsuroi sp. nov. from Honshû, Kyûshû and Nansei-shotô, B. moriguchii sp. nov. from Nansei-shotô, B. nigra sp. nov. from Honshû, Shikoku, Kyûshû and Nansei-shotô, B. okinawana sp. nov. from Nansei-shotô, B. yoshigoui sp. nov. from Honshû) are described. Additional descriptions and records for the two species (B. koreana Ahn & Jeon, 2004 and B. japonica Liu, Ono & Maruyama, 2020) which are currently described/redescribed are given. Mouthparts and sexual organs of both sexes of all species are illustrated. A key to the Japanese species and distribution map of these species are provided. The habitats and behaviour of some representatives are reported, and the distributional range related to flight ability is discussed.

A Juvenile Specimen of Archaeorhynchus Sheds New Light on the Ontogeny of Basal Euornithines

The ontogenetic development of extant birds is characterized by rapid growth, bone fusion and an early onset of flight ability. In contrast, little is known about how these ontogenetic traits evolved in the bird stem lineage, and the available data pertains primarily to Enantiornithes. Here, we describe an almost complete skeleton of a juvenile euornithine bird (LNTU-WLMP-18) from the Early Cretaceous Jiufotang Formation (Aptian), which was discovered near Lamadong Town (Jianchang County, Liaoning, China). Despite its completeness, bone preservation is rather poor. Thus, to increase the contrast between bone tissue and matrix, we used cyan-red-based autofluorescence photography. The specimen is more or less articulated and exposed in ventral aspect. The jaws are edentulous, the coracoid bears a procoracoid process, and the ischium lacks a proximodorsal process. The pedal unguals are short and barely curved, indicating a ground-dwelling lifestyle. Feathers, including long primaries, are present as carbonized traces. Several characters indicate that LNTU-WLMP-18 is a juvenile: the bone surface has a coarsely striated texture and no fusion is evident between the carpals and metacarpals, between the tibia and the astragalus and calcaneum, or among the metatarsals. Although juvenile characters have the potential to impede accurate identification of the specimen, morphological comparisons and cladistic analysis identify LNTU-WLMP-18 as most likely referable to the basal euornithine Archaeorhynchus, which would make the specimen the first juvenile bird from the Jehol Group that could be assigned to a specific taxon. Based on its size and the incomplete ossification of the bone surface, LNTU-WLMP-18 represents the smallest and therefore youngest known individual of this genus. A statistical comparison of limb proportions shows that the forelimbs of LNTU-WLMP-18 are significantly shorter than the hindlimbs, while the forelimbs are longer than the hindlimbs in subadult and adult individuals. This is different from the situation in some Enantiornithes, in which the forelimbs exceed the length of the hindlimbs even in hatchlings. Similar to Enantiornithes, Archaeorhynchus probably exhibit an early onset of flight ability, as indicated by the extensive wing plumage in LNTU-WLMP-18. Finally, the lack of gastroliths in the visceral cavity might indicate a dietary shift in Archaeorhynchus during ontogeny. As a small-bodied, ground-dwelling, seed-eating bird with a precocial ontogeny, Archaeorhynchus filled an ecological niche that later allowed early crown birds to survive the K-Pg mass extinction.

Evaluation of different blood-feeding frequencies on Glossina palpalis gambiensis performance in a mass-rearing insectary

Background The main challenge to the successful mass-rearing of the tsetse fly in insectaries, especially in Africa, is a sustainable supply of high-quality blood meals. As such, the collection of high-quality blood in large quantities can be an important constraint to production. One possible strategy to lessen the impact of this constraint is to modify the blood-feeding frequency. In the study reported here, we evaluated the effect of three blood-feeding frequencies on the colony performance of Glossina palpalis gambiensis, a riverine tsetse fly species. Methods The effect of three, four and six blood-feedings per week on female survival and productivity were evaluated over a 30-day period. Progeny emergence rate and flight ability were also evaluated. Results Female survival was significantly higher in flies fed four times per week (87%) than in those fed three (72%) and six times per week (78%; P < 0.05). Productivity was similar between flies fed four and six times per week (457 and 454 larvae) but significantly reduced in flies fed three times per week (280 larvae produced; P < 0.05). Both emergence rate and flight ability rate were also similar between flies fed four times per week (97 and 94%, respectively) and six times per week (96 and 97%, respectively), but they were significantly reduced when flies were fed three times per week (89 and 84%, respectively; P < 0.05). Conclusions Blood-feeding frequency could be reduced from six times per week to four times per week without affecting mass-rearing production and progeny quality. The implications of these results on tsetse mass-rearing production are discussed.

Evaluation of different blood feeding frequencies on Glossina palpalis gambiensis performance in a mass-rearing insectary

Background: In tsetse fly mass-rearing insectaries, the sustainable supply of high quality blood meals is the main challenge, especially in Africa. Because the collection of high quality blood in large quantities may be an important constraint to production, blood feeding frequency can be a lever to lessen its impact. Therefore, this study evaluates three blood feeding frequencies on Glossina palpalis gambiensis colony performance.Methods: Three effects of blood feeding treatments - three, four and six times per week - were evaluated on female survival and productivity over a 30-day period. Progeny emergence rate and flight ability were also evaluated.Results: Female survival was significantly higher for flies fed four times per week (87%) than three (72%) and six times (78%; p<0.05). Productivity was similar between flies fed four and six times per week (457 and 454 larvae) but significantly reduced when fed three times (280 larvae produced; p<0.05). Similarly, emergence rate and flight ability rate were both similar between flies fed four times (97% and 94%) and six times (96% and 97%) per week but significantly reduced when fed three times per week (89% and 84%, respectively; p<0.05).Conclusions: Blood feeding frequency could be reduced to four times per week without affecting mass-rearing production and progeny quality. We discuss the implications of these results on tsetse mass-rearing production.