Catches of yellowjackets (Hymenoptera: Vespidae) in traps baited with proteinaceous baits or a heptyl butyrate–based synthetic chemical lure in British Columbia, Canada, and Rio Negro, Argentina, differed among species. In British Columbia, western yellowjackets, Vespula pensylvanica (Saussure), responded preferentially to traps baited with rotisserie chicken (Galliformes: Phasianidae) over canned chicken or canned sardines (Clupeiformes, Clupeoidei), but the synthetic chemical lure was more attractive than rotisserie chicken. Counterintuitively, when rotisserie chicken and the synthetic chemical lure were combined, catches were reduced. In British Columbia, more German yellowjackets, V. germanica Fabricius, were caught in traps baited with rotisserie chicken than with canned chicken, and in Argentina, both German and common, V. vulgaris Linnaeus, yellowjackets preferred sardine-flavoured cat (Carnivora: Felidae) food over the synthetic chemical lure. In British Columbia, northern yellowjackets, V. alascensis (Packard), showed no preference among three types of chicken or between rotisserie chicken and canned sardines. When rotisserie chicken and the synthetic chemical lure were combined, catches of both northern and German yellowjackets were no higher than when traps were baited with rotisserie chicken alone. Resolution of the differential roles of red meat-, poultry-, and fish-based baits, as well as improvement of synthetic chemical lures, would be facilitated by identification of bioactive semiochemicals.

Two new species of giant lacewings (Neuroptera: Polystoechotidae) are described from Ypresian Okanagan Highlands localities in western North America: Palaeopsychops goodwini sp. nov. and Palaeopsychops barthae sp. nov., both from Republic, Washington, United States of America, and a less well-preserved specimen is treated as Palaeopsychops sp. indet., the first occurrence of the family at McAbee, British Columbia, Canada. These share distinctive wing colouration – dark with a single pale, broad fascia mid-wing.

Females may adjust how many eggs they lay over the course of their lifetime (i.e., their egg-laying pattern) to bias their investment into either current or future reproduction. Using mate availability cues to bias reproductive investment could ensure that females obtain the benefits of multiple mating when future mate availability is high or low. We studied whether perceived mate availability influenced egg-laying patterns in Teleogryllus oceanicus Le Guillou (Orthoptera: Gryllidae), the Pacific field cricket, and whether variation in those patterns affected females’ future egg-laying or total reproductive output. On hearing the male calling song to simulate high mate availability, females did not alter their egg-laying patterns relative to females that did not hear the song. The lack of influence of perceived mate availability on egg-laying patterns is noteworthy because this treatment affects many other aspects of this species’ reproductive investment. Neither investing highly in current versus future egg-laying nor having a highly variable egg-laying pattern appeared to be costly in this species. Despite consistent conditions and sufficient resources for females during the experiment, our fine-scale study of egg-laying patterns highlights the variability that exists in these patterns, and we speculate on some factors that may drive this variation.

Bacteria play a fundamental but often overlooked role in shaping insect communities in cattle (Bovidae) dung. To direct attention to this role, three experiments were performed with cattle dung autoclaved to reduce bacterial activity and the associated release of volatile organic compounds (VOCs) that attract coprophilous insects to deposits. In the first experiment, and consistent with expectations, fewer insects were recovered in pitfall traps baited with autoclaved versus control dung. In the second experiment, there was generally lower recovery of insects developing in autoclaved versus control pats colonised in the field. This result was attributed to reduced oviposition and lower survival of immature insects in the autoclaved pats. In the third experiment, no effect of autoclaved versus control dung was detected on the reproductive success of the dung beetle Onthophagus taurus (Linnaeus) (Coleoptera: Scarabaeidae), possibly because adults carry with them the requisite bacteria for larval development. In summary, faecal bacteria produce VOCs to directly affect the composition of the insect species that colonise and oviposit in cattle dung. The survival of their progeny is affected by faecal bacteria that provide a source of nutrients or may be pathogenic.

Spiders (Araneae) are an abundant and diverse arthropod group that serve important ecosystem functions in boreal forests. Several hundred species across boreal Canada are prey for vertebrates and invertebrates. Spiders are also generalist predators that likely contribute to pest control. Our understanding of spider assemblages, particularly of the arboreal community, is minimal at the stand level in many habitats across Canada. Habitat-specific factors like connectivity, microclimate, and neighbour effects can substantially influence the structure of ecological communities. Well-replicated landscape-scale experimental designs enable us to better understand the structure of arboreal spider communities. Here, we employed beat-sheeting to characterise spider assemblages on balsam fir trees (Pinaceae) from the three most common stand types found in the boreal: coniferous, deciduous, and mixedwood. Fir trees in deciduous stands had greater spider abundance than did the trees in coniferous or mixedwood stands. Neither species diversity nor composition differed significantly among the three stand types. Our results suggest that spiders likely do not recognise “the forest for the trees.”

The fly Heleomyza serrata (Linnaeus) (Diptera: Heleomyzidae) is reported to range widely throughout the United States of America and Canada. However, in Eurasia, this species is restricted to northern regions; in central and southern Europe, H. serrata is replaced by the similar species H. captiosa (Gorodkov), which can be distinguished from H. serrata by the male genitalia. We report H. captiosa from Kentucky, United States of America, the first Nearctic record of this species. The taxonomy of Nearctic Heleomyza Fallén is discussed, and we propose to transfer three species to the genus Scoliocentra Loew: Scoliocentra (Scoliocentra) bisetata (Garrett) comb. nov., S. (Leriola Gorodkov) latens (Aldrich) comb. nov., and S. (L.) nebulosa (Coquillett) comb. nov. We recognise Anypotacta Czerny as a subgenus of Heleomyza and transfer the two Nearctic species to that genus: H. (A.) aldrichi Garrett comb. nov. and H. (A.) gilli nom. nov. (new replacement name for Anypotacta czernyi Gill, 1962). Finally, we provide an updated key to Nearctic Heleomyza and morphologically similar species of Scoliocentra. Further study will be required to ascertain the range and abundance of H. captiosa in North America.

Climate change and other anthropogenic stressors are reshaping Earth’s biodiversity, motivating efforts to monitor changing faunal diversity. Canada is home to 80 documented species of mosquitoes, 38 of which are reported in New Brunswick. Using Centers for Disease Control and Prevention miniature CO2 light traps, three adult mosquito collection surveys were performed to encompass 43 trapping sites across New Brunswick, Canada. Study one took place from 21 July 2022 to 9 September 2022, study two took place from 29 May 2023 to 24 October 2023, and study three took place from 15 May 2024 to 19 September 2024. Among the specimens collected, a total of 18 Uranotaenia sapphirina (Osten Sacken) (Diptera: Culicidae) were identified from five separate trapping sites. This species, previously documented only in Ontario, Quebec, and Manitoba, is considered rare in Canada and is known for its specialisation in feeding on annelids rather than vertebrates. Our detection of Ur. sapphirina in New Brunswick, where it has been absent in earlier surveys, suggests a recent range expansion, possibly driven by climate change. This observation highlights the need for ongoing surveillance to monitor the impacts of environmental changes on mosquito distribution.

Four Palaearctic species of Staphylininae (Coleoptera: Staphylinidae) are reported from North America for the first time: Heterothops cognatus Sharp, H. praevius (Erichson), Philonthus chujoi Dvořák, and Quedius (Raphirus) maurorufus (Gravenhorst). We suspect that these species are part of a more recent cohort of accidental introductions to North America. Notably, two of them are native to the East Palaearctic, an unusual source of adventive staphylinids in North America because nearly all others are native to Central Europe. We suggest that the East Palaearctic is an underrecognised and increasingly important source for recently adventive soil invertebrates and that increased taxonomic focus on this fauna is important to North American biosecurity. The detection of trans-Palaearctic H. praevius resulted in the recognition of H. praevius Erichson (= H. marmotae Smetana syn. nov.). We also newly report the Nearctic species Heterothops conformis Smetana and H. sordidus Smetana from eastern North America. Philonthus debilis, a close relative of P. chujoi, is reported from the Yukon Territory, representing the northernmost locality known for this long-established adventive species. Illustrations of diagnostic features, barcode data, and distribution maps are provided for all four species. Updated or new identification keys are provided to aid in the recognition of these species in eastern North America.

The Noctuidae (Lepidoptera) comprise the most diverse and abundant lepidopteran families in the Canadian Prairie Ecozone. Within this group, some species are agricultural pests that require monitoring. Pheromone lures target specific species, whereas food-bait lures attract a broader range. This study reports the diversity and abundance of noctuid moths captured in traps baited with female sex pheromones of pest species and with food-bait lures consisting of acetic acid and 3-methyl-1-butanol (AAMB) with fermented byproduct or floral volatile compounds. Food-bait lures that attract pests and nonpest species can provide insight into moth populations and species richness in human-managed ecosystems. We trapped moths in wheat (Poaceae) and canola (Brassicaceae) fields in central Alberta, Canada. We captured and identified to species approximately 7900 noctuid moths. Community composition was similar in both crops. Sex pheromone–baited traps had variable specificity and low nontarget diversity. Traps baited with AAMB captured greater moth diversity than unbaited traps did. Noctuinae were the most diverse and abundant in AAMB-baited traps (62 species across 8 tribes). The AAMB lures captured more cutworm and armyworm pests than unbaited traps did. Fermented byproduct food–bait lures captured more noctuid pests than floral volatiles did. The AAMB lures can be implemented to monitor Noctuinae diversity and potentially assess local noctuid pest density in agroecosystems on the Canadian prairies.

Metarhizium guizhouense (Clavicipitaceae) is an insect pathogen employed as a mycoinsecticide against many insect pests worldwide. In this study, for the first time in a laboratory setting, the pathogenicity of the M. guizhouense isolate PSUM04 was evaluated against the coffee berry borer, Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae). Following the exposure (1 × 109 spores/mL) of H. hampei to M. guizhouense PSUM04, morpho-histopathological changes and numbers of apoptotic cells via the TUNEL (terminal deoxynucleotidyl transferase (TdT), dUTP (deoxyuridine triphosphate) nick-end labelling) assay in H. hampei were evaluated at 12-hour intervals until 144 hours after exposure. The external morphology of H. hampei underwent drastic changes from 24 to 144 hours post-exposure accompanied by the degeneration of integument and adipose tissues. The semi-quantitative analytical score of TUNEL-positive cells showed a slight increase at 12 hours after exposure and a significant increase in TUNEL-positive apoptotic cells at 48 hours after exposure. These results suggest a series of tissue alterations of H. hampei during its process of infection with a strain of M. guizhouense, highlighting the pathogen’s potential as a biological control agent in natural settings.

Nonnative earthworm species are invading the boreal forest in North America. Oribatid mites are key detritivores in boreal forest soils, initiating litter decomposition and maintaining forest floor structure. Earthworms are also detritivores and are considered ecosystem engineers. When introduced into nonendemic environments, earthworms may alter soil biogeochemical cycling and adversely affect oribatid mite communities. However, to our knowledge, no field studies in boreal forests have investigated invasive earthworms and their impacts on oribatid mites. The present study was conducted in a boreal trembling aspen, Populus tremuloides Michaux (Salicaceae), stand near Wolf Lake, Alberta, Canada. After assessing the current state of earthworm invasion, we identified an area with a lower density of earthworms that was invaded by one species, Dendrobaena octaedra Savigny (Crassiclitellata: Lumbricidae), and an area with a higher density of earthworms that was invaded by multiple species, D. octaedra (Crassiclitellata: Lumbricidae) and Aporrectodea spp. (Crassiclitellata: Lumbricidae). The higher-density area was associated with lower understorey vegetation species richness and with thinner forest floors characterised by higher bulk density but lower total organic carbon and nitrogen stocks. Oribatid mite community composition differed between the two areas, and their richness significantly decreased with higher earthworm density. Our findings suggest that earthworm invasion is substantially disrupting habitat for oribatid mites and might affect the overall boreal ecosystem equilibrium in the long term.

The field of Quaternary entomology has focused primarily on the study of beetles (Coleoptera) and, to a lesser degree, nonbiting midges (Diptera: Chironomidae). Beetles typically predominate because they have heavily sclerotised exoskeletons, and they are abundant in a great variety of habitats. Because of taphonomy and scarcity, other Quaternary invertebrates have been less studied. Only a few records of fleas (Siphonaptera) and mites (Acari) are reported from Pleistocene deposits that span the Seward Peninsula in Alaska, United States of America, to the Klondike goldfields in central Yukon Territory, Canada. Grasshoppers (Orthoptera) and thrips (Thysanoptera) have not been reported previously from Quaternary deposits across the Arctic’s Beringia region. However, recent extensive sampling of Arctic ground squirrel, Urocitellus parryii Richardson (Rodentia: Sciuridae), middens from permafrost deposits of the Klondike goldfields has yielded specimens from each of these underrepresented invertebrate groups. Here, we present records of fleas (Oropsylla alaskensis Baker (Ceratophyllidae)), mites (including Fusacarus Michael (Astigmata: Glycyphagidae) and cf. Haemogamasus Berlese (Mesostigmata: Laelapidae)), and the first records of grasshoppers (Acrididae: Gomphocerinae) and thrips (Thysanoptera: Thripidae) from Beringia from six middens spanning approximately 80 000–13 500 years BP. We also provide brief reviews of the fossil history of each major taxon.

An important component of post-release monitoring of biological control of invasive plants is the tracking of species interactions. During post-release monitoring following the initial releases of the weevil Ceutorhynchus scrobicollis Nerenscheimer and Wagner (Coleoptera: Curculionidae) on garlic mustard, Alliaria petiolata (Marschall von Bieberstein) Cavara and Grande (Brassicaceae), in Ontario, Canada, we identified the presence of larvae of the tumbling flower beetle, Mordellina ancilla Leconte (Coleoptera: Mordellidae), in garlic mustard stems. This study documents the life history of M. ancilla on garlic mustard to assess for potential interactions between M. ancilla and C. scrobicollis as a biological control agent. Garlic mustard stems were sampled at eight sites across southern Ontario and throughout the course of one year to record the prevalence of this association and to observe its life cycle on the plant. We found M. ancilla to be a widespread stem-borer of late second–year and dead garlic mustard plants across sampling locations. This is the first host record for M. ancilla on garlic mustard. The observed life cycle of M. ancilla indicates that it is unlikely to negatively impact the growth and reproduction of garlic mustard and that it is unlikely to affect the use of C. scrobicollis as a biological control agent.

Variation in wild bee assemblages along climatic gradients is still poorly known, particularly in eastern Canada. In this study, we assessed wild bee communities in forest stands that were recently clearcut along a latitudinal bioclimatic gradient. The analyses were conducted at two taxonomic levels: first at the genus level for bees as a whole (Anthophila) and then at the species level for bumble bees (Bombus spp. Latreille) (Hymenoptera: Apidae). Coloured pan traps were used to catch bees and a point-intercept method was used to survey floristic composition at each site. Abundance and richness of Anthophila genera and abundance of bumble bee species were inversely related to latitude, but richness of bumble bee species was not, being instead associated with sections of the gradient. These results indicate that the relationship between wild bee diversity and latitude varies among taxa and that climate and floristic resources probably each play a role. Bombus terricola, a species of concern in eastern Canada, was found in relatively high numbers throughout the study area. To our knowledge, this study provides the first assessment of wild bees in clearcuts in the province of Quebec, showing a clear differentiation of the communities along a spatial bioclimatic gradient.

Gardens have emerged as a key habitat resource for pollinators in cities, but more research is needed to determine the optimal garden characteristics for maximising native pollinator diversity. Syrphid flies (Diptera: Syrphidae) are abundant generalist fly pollinators that have received less study than other pollinators in urban gardens. In this study, we investigated whether flowering plant diversity and the presence of native plants were related to syrphid abundance and diversity in urban street gardens. Over a two-month period, we sampled 12 small public gardens in a residential urban area (Vancouver, British Columbia, Canada) to explore correlations between plant and syrphid assemblages. Gardens reflected the relative scarcity of native plants in our study system, such that gardens with native flowers present ranged from 10 to 60% cover. Although syrphid abundance and richness varied among gardens, neither floral richness nor the presence of native flowers was correlated with syrphid abundance or diversity. Beyond plant diversity and origin, other characteristics may be more important to syrphid visitation at the garden scale. A better understanding of the role of garden characteristics among the complex factors shaping urban syrphid assemblages will offer valuable insights for the improvement of pollinator conservation strategies.

Ball sampling is an active technique of sampling the upper canopy of hemlock, Tsuga sp. (Pinaceae), to detect the nonnative hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae). We tested a 7.5-cm-diameter wooden ball fitted with Velcro® with a BigShot® slingshot that sends the ball into the upper hemlock canopy. The 7.5-cm ball detected wool with fewer sampling attempts per tree and had a higher detection rate after 10 sampling attempts than a 5-cm wooden ball using a much smaller HyperDog® slingshot did. However, sampling with the 7.5-cm ball took 20% longer per tree and fatigued shooters after only 30–40 shots due to the size and effort required to use the larger slingshot. A larger sampling device (= greater Velcro® surface area) significantly improved detection of adelgid wool and is recommended, provided a more efficient launching system is developed.

Outbreaks caused by migrant pests such as the armyworm, Mythimna unipuncta (Haworth, 1809) (Lepidoptera: Noctuidae), are generally unpredictable. In the province of Quebec, Canada, the arrival and dispersal of armyworms is monitored by capturing males using pheromone traps. Because only males are captured in pheromone-baited traps, trap catch is not predictive of subsequent larval occurrence and damage. We used traps baited with a feeding attractant to capture both male and female armyworm moths and evaluate their flight period at 11 sites across the province in 2018 and 2019. The reproductive status of females was also investigated by dissecting their reproductive apparatus to determine if they were sexually active when captured. The results showed two peak flight periods between May and August but high variation at the different sites and between years. Both sexes migrate in Quebec at the same time but in variable and unpredictable proportions. All spring migrant females had mated before capture, whereas some unmated females were captured later in the season. These results provide useful information to better monitor the armyworm in Quebec and to develop more appropriate integrated pest management strategies.

A subfossil robber fly (Diptera: Asilidae) from the genus Lasiopogon Loew is reported from a Beringian rodent, Arctic ground squirrel, Urocitellus parryii Richardson (Rodentia: Sciuridae), midden in the Yukon Territory, Canada, dated to about 16 500 years old. This is the first asilid reported from Quaternary-aged material and represents the first (sub)fossil for this genus and for the subfamily Stichopogoninae.

The dung-burying activities of paracoprid dung beetles such as Onthophagus nuchicornis Linnaeus (Coleoptera: Scarabaeidae) are known to improve nutrient cycling, decrease greenhouse gas emissions, and reduce parasite transmission. These benefits are closely associated with the quantity of dung buried and the depth at which the nest is built; however, comparatively little research has focused on the role of underground nest architecture in underpinning ecosystem function. The use of three-dimensional (3D) printing has facilitated the use of innovative models, tools, and methods in recent ecological studies. Although past attempts have been made to construct paracoprid beetle observation chambers from wood, to our knowledge, 3D printing has not yet been used for this purpose. We designed a 3D-printed observation chamber that allowed us to view the placement and rate of brood-ball production. Initial trials of our design indicate that, with adjustment of the chamber interpane width, tunnelling and brood-ball activity can be monitored without limiting the activity of the captive beetles. Noninvasive observation of underground activity using 3D-printed observation chambers is cost and time effective, and it offers a number of practical advantages over traditional wooden designs. These improvements may facilitate observations and contribute to our understanding of ecosystem functions provided by paracoprid dung beetles.

The developmental environment can have an especially large impact on life history plasticity in animals, influencing body size, reproductive success, and longevity. This is because developmental processes interact with environmental factors to determine phenotypes such as body size, sexual investment, and metabolic rate, which in turn can influence longevity and senescence. We investigated how natural differences in the larval environment (discarded moose antlers) influenced development time, survival, and mating success of wild male antler flies, Protopiophila litigata Bonduriansky (Diptera: Piophilidae). Antlers become depleted of resources from year to year, as multiple generations of larvae feed within them. We collected larvae that grew inside nine different shed moose antlers, and we individually tracked them in the field as adults. Moose antlers that were more attractive to adult P. litigata also supported a greater number of larvae, suggesting they are of higher quality. Flies that developed in more attractive antlers completed metamorphosis more quickly but did not differ in body size, longevity, or lifetime mating success. This suggests that the observed differences in larval density may, in part, balance the variation in resource availability among antlers. Regardless of natal antler, large male P. litigata tended to live longer and have higher mating success, as found in previous studies of this species.