Austral Entomology最新文献

Pyrethroid resistance in the redlegged earth mite (Halotydeus destructor) continues to be a persistent and expanding problem across the grain belt of Australia, requiring ongoing monitoring to detect emerging local resistance issues. Detection of field resistance in H. destructor currently relies upon the collection and transport of live mites, followed by laborious experiments involving laboratory pesticide bioassays or fairly complex genetic screening assays. Both approaches require trained scientists and are time-consuming and therefore do not provide rapid feedback to farmers. To facilitate the rapid detection of resistance issues, we developed a novel bioassay that can be readily applied in the field using commercially available materials and without the need for training. Although effective in detecting field resistance, this approach was found to be unsuitable in situations where the resistance allele frequency within a mite population was low. To address this limitation, we developed a loop-mediated isothermal amplification (LAMP)-based assay. This approach was successful in distinguishing between homozygote (SS) and heterozygote (RS) mites and, therefore, capable of detecting resistance at low frequency. These tools should help in the ongoing real-time monitoring of resistance in this important agricultural pest.

Termites are important ecosystem engineers in many ecosystems globally. Hence, surveys of termite species composition, abundance and activity can be important for understanding ecosystem function—especially in biomes where they tend to be abundant, such as tropical savannas. However, comprehensively surveying termites can be challenging due to their cryptic nature and varied feeding and nesting habits, which strongly influence the effectiveness of different survey methods. Baiting and active searches of reduced transects are two methods commonly used to sample termites, and while these methods have been evaluated in the savannas of South Africa, this has not occurred in the extensive tropical savannas of northern Australia. Thus, this study evaluated the effectiveness of baits and reduced transects to assess termite species richness and activity across 18 × 1 ha experimental plots in a tropical savanna near Darwin, Australia. Surveys in each plot consisted of two 60 × 2 m transects and a 9 × 3 baiting grid of alternating buried wood and paper baits and surface straw baits. Baits were checked three times: at 4-, 7- and 10-week intervals following placement. Upon survey completion, the sampling effort, efficacy and costs of each method were compared. Reduced transects detected all 32 species recorded in this study, representing four feeding groups (from undecayed wood to highly decayed organic material in the soil). Baiting detected 20 species, but failed to detect some of the species that fed on decayed materials. Paper baits, checked only twice (at 4 and 10 weeks following placement), were required to detect all species sampled at both wood and paper baits. Therefore, overall baiting costs could be reduced (without data loss) by using paper baits only and reducing the number of bait checks. Compared with baiting using all three bait types, reduced transects detected the most species and had the lowest per-species cost. Consequently, reduced transect surveys are the most effective method in these northern Australian savannas when assessing species composition. However, if the abundance of species that feed on undecayed wood or levels of termite activity are being assessed, then reduced baiting is a more appropriate method.

No abstract is available for this article.

Seven new species of Rhopalomyia Rübsaamen, 1892 are described from eastern Australia feeding on a diverse range of plant genera and families. All induce galls on flower or growth buds: Rhopalomyia cassiniae Adair & Kolesik, sp. nov. on Cassinia subtropica (Asteraceae), Rhopalomyia digitata Adair & Kolesik, sp. nov. on Podolobium ilicifolium (Fabaceae), Rhopalomyia glebosa Adair & Kolesik, sp. nov. on Parsonsia straminea (Apocynaceae), Rhopalomyia inconspicua Adair & Kolesik, sp. nov. on Kunzea sp. (Myrtaceae), Rhopalomyia ozothamniae Adair & Kolesik, sp. nov. on Ozothamnus ferrugineus (Asteraceae), Rhopalomyia pultenicola Adair & Kolesik, sp. nov. on Pultenaea forsythiana (Fabaceae) and Rhopalomyia stypheliae Adair & Kolesik, sp. nov. on Syphelia triflora (Ericaceae). The scope of Rhopalomyia is broadened to contain species with a partially setulose gonostyle and a four-segmented palp, a decision supported by a phylogenetic analysis based on the barcoding section of the mitochondrial COI gene. Apocynaceae, Ericaceae, Fabaceae and Myrtaceae are recorded as hosts of Rhopalomyia for the first time.

A new genus, Prytanoides gen. nov., is described to accommodate the new species Prytanoides prorrectus gen. et sp. nov. from Argentina. Its relationship with the presumably closely related Prytanes Distant,1893 is discussed. The distributional range of four Prytanes species is also extended: Prytanes formosus (Distant, 1882) and Prytanes foedus (Stål, 1860) are recorded for many provinces in Argentina; Prytanes oblongus (Stål, 1862) is recorded from Ecuador for the first time; and Prytanes tumens (Stål, 1874) from Mexico. For each species, we provide a colour habitus of the adult, together with photographs of the male genitalia of the new genus and species.

A new genus and species of Strepsiptera, Chrysostylops australiensis Benda & Straka, gen. et sp. nov., is described. It represents the first record of the family Stylopidae from Australia. It was parasitising the bee species Chrysocolletes aureus Leijs & Hogendoorn, 2021 (Neopasiphaeinae). The diagnosis and description of the genus and species are provided based on the characters of the female cephalothorax. Diagnostic characters are discussed. The male and first instar larvae of C. australiensis are unknown. We removed Hylecthrini Ulrich, 1930 reinst. stat. from synonymy based on the specific sculpture on the female cephalothorax. The tribe is specialised for bees of the family Colletidae.

Cryptotermes brevis (Walker) (Blattodea: Kalotermitidae) is one of the most destructive drywood termites that attack moisture-protected timber in service. Heat treatment has been studied to control these termites, but the low thermal conductivity of wood can result in prolonged treatment times and the need for high temperatures to eliminate termite colonies. The current study investigated heat transfer through a heat transfer model and experiments within solid timber boards and a representative wall section. The aim was to optimise targeted spot heat treatment as a cost-effective method for eradicating this pest within structural elements. Through experimental work and the development of a deterministic heat transfer model, valuable insights were gained into temperature distribution within wooden structural elements. The findings revealed that proximity to the heated surface played a crucial role, with closer distances reaching equilibrium temperatures faster. The heat transfer model, validated against experimental data, accurately predicted temperature distributions within the timber. Termite survival was significantly influenced by heating time and distance from the heated surface when a wall section was heated at 60°C. The mean survival of C. brevis pseudergates kept inside wall studs varied from 30% to 96.7% depending on the distance from the heated surface after 1.5 h of heating, where the temperature ranged from 43°C to 45°C. However, after extending the heating duration to 3 h, the temperature in wall studs was elevated to 51°C, 49°C and 47°C at 22, 40 and 60 mm from the heated stud face, respectively. All C. brevis pseudergates across all distances were killed at a 3-h duration. This research underscores the importance of understanding temperature distribution in structural wood elements and exposure times when employing heat as a spot treatment for drywood termite control.

Understanding the spatiotemporal distribution of diversity has been a significant challenge in the field of conservation biology. Presently, there exists a limited understanding of the spatial distribution of passalid beetles within decomposing logs, as well as their distribution in microhabitats such as the cortex, heartwood and trunk–soil interface. Moreover, there is a scarcity of studies that delve into the temporal distribution patterns of passalid beetles. We evaluate the effect of seasons of the year and microhabitats on the distribution of passalid in an Altitudinal Atlantic Forest. More specifically, the effects of the period of the year and microhabitats were analysed on an assemblage scale and population structure scale. Collections were actively conducted monthly, during dry and rainy seasons, and distinct microhabitats of logs (tree cortex, heartwood and trunk–soil interface) were sampled. We discovered passalid galleries within 235 logs, housing a total of 785 individuals representing nine species across six genera and two tribes. Within the three examined microhabitats, the heartwood and cortex harboured the majority of individuals. In contrast, the trunk–soil interface microhabitat displayed reduced diversity and abundance and the absence of indicator species, exhibiting a distinct community structure compared with the others. The dry season stood out with a greater number of individuals, underscoring the influence of precipitation on passalid activity in this study. Our study contributes to understanding the ecological dynamics of these insects and evaluating their resilience to current landscape transformations on the planet.

The Bag-shelter moth, Ochrogaster lunifer (Lepidoptera: Notodontidae), is an Australian endemic species of Thaumetopoeinae with a univoltine life cycle and gregarious, herbivorous larvae. It is variable throughout its range across the continent, most noticeably by the species of host tree used and nest-building behaviour. It has long been considered a species complex by some taxonomists, and the lack of gene flow between populations of ground-nesters and above-ground nesters at the same sites provides strong evidence for at least two species. We tested the specificity of host use and nesting behaviour of ground-nesting and trunk-nesting forms of O. lunifer by transplanting field-collected egg masses to the other form's host, either in their natural position or in the position used by the other form. At the study site, ground-nesting and trunk-nesting (tree-hugger) O. lunifer coexist. Ground-nesting larvae are found on Acacia spp., and egg masses are laid at the base of host tree trunks where nests develop whereas tree-hugger larvae are found on Blakella tessellaris, egg masses are laid in the outer canopy, and nests develop on the trunk or large branches. Of the 47 egg masses of O. lunifer transplanted to the unnatural host, only one cohort of tree-hugger larvae developed through to adult moths. Placing an egg mass in its unnatural position on its natural host did not prevent the larvae from developing and successfully establishing nests for either nesting-form, although all the ground-nesters moved position (from the canopy to the ground) and the tree-huggers mostly did not (from the ground to the canopy). Only the tree-hugger form of O. lunifer developed a viable nest on the unnatural host species, established a nest at the unnatural oviposition site, and shared that nest with larvae of the other nesting-form, suggesting tree-hugger larvae are somewhat plastic in their behaviour and ecology. Our findings add to previous studies indicating that Acacia is likely the ancestral host of O. lunifer though large areas of its range remain unstudied.

Glowworms are the bioluminescent larvae of a group of dipteran insects related to fungus gnats. They require sheltered, consistently moist conditions and are found in aggregations on the walls and ceilings of caves and near streams in wet forests where they attract flying insects as prey. The Waitomo Glowworm Cave in New Zealand receives many thousands of visitors each year to see the colony of the glowworm, Arachnocampa luminosa. The cave climate is managed to ensure the glowworms are not harmed by influxes of dry air, as happened in the 1970s. To monitor the population and warn of catastrophic population declines, time-lapse photographic monitoring of the glowworm population began in 2011 using a permanent, fixed camera. Photographs are taken 30 min apart. The population exhibits synchronised diurnal cycles of bioluminescence intensity. The time of the acrophase (the peak) of the diurnal cycle varied seasonally between 5 pm in early southern spring and 8 pm in summer. Cross-correlation analyses with cave and water temperatures incorporating time lags suggest that this annual cycle could be related to changes in the composition or density of prey insects. Annual cycles also occur in the number of glowing larvae and their overall intensity. In most years, the numbers are lowest in winter and increase in spring to produce the brightest display through summer. The summer peak is not seen every year and autocorrelation of the 13-year time series of count shows signs of a 3- to 4-year cycle beyond the annual periodicity. The availability of prey in the cave chamber could influence the annual cycles in glowworm density, underscoring the need for a deeper knowledge of the bionomics of prey species, mainly Chironomidae (non-biting midges). The photographic monitoring has proven to be a useful component of the management of the glowworm population.