Laboratory experiments and field observations from August 2019 to April 2020 demonstrated that skipper flies (Diptera: Piophilidae) overwinter as larvae and likely present an obligatory winter diapause in Québec, Canada. Diapause was confirmed by the very few emergences of adults in the laboratory following collection from carrion at the end of summer and in fall, the migration of larvae deep in the soil, and the persistence of larvae inside carrion during the winter until the following spring when they became active again and initiated pupation (i.e., intra-puparial period). To our knowledge, our observations represent the first report of the overwintering of skipper fly larvae inside an animal carcass in North America. In addition, this winter diapause should be considered in forensic entomology when using the presence of skipper fly larvae on a body to estimate the time elapsed since death.

The crucifer flea beetle, Phyllotreta cruciferae (Goeze) (Coleoptera: Chrysomelidae), is the most important pest of seedling canola, Brassica napus Linnaeus (Brassicaceae), in North America, yet effects of weather on its dispersal and flight activity are not completely understood. We investigated effects of ambient temperature, relative humidity, wind speed, atmospheric pressure, barometric flux, and precipitation on capture heights of P. cruciferae over four site-years in Alberta and Saskatchewan, Canada. Capture heights increased with mean ambient temperatures for both generations of beetles, with 15°C determined as an estimated minimum temperature for flight. Although capture heights decreased with greater minimum relative humidity, and atmospheric pressure, and increased with greater mean wind speed, the contributions of these factors were determined to be minor relative to that of mean temperature. Results of the current study will contribute to more accurate predictions of the invasion of canola crops by P. cruciferae and contribute to improved integrated management of this important pest species.

It was found that five different starches incorporated into artificial diet in place of sucrose made the diets significantly less nutritious for spruce budworm larvae (Choristoneura fumiferana (Clem.)).

The applicability of this to the natural situation — budworm larvae feeding on growing foliage — is unknown.

This paper records the Hemiptera of the superfamily Scutelleroidea (Burmeister) now in the collection of the Utah Agricultural Experiment Station. The writers wish to thank Dr. E. P. Van Duzee for his kindness in determining a series of specimens, by comparison with which the remainder of the collection was named. The purpose of this list is to give additional information as to the occurrence, distribution, abundance, and note damage by the forms of economic importance.

Predation on spruce-budworm, Choristoneura fumiferana (Clem.), pupae on the forest floor was estimated at 72.5% per day. It is unlikely that many adults of the spruce budworm emerge from the forest floor and there would be little bias introduced in the estimation of apparent fecundity by disregarding pupae on the ground. There were large seasonal fluctuations in the rate of predation attributable to various predator groups; the overall rate ranged from 66 to 91% per day. Low temperatures had no detectable effect on vertebrate predation, but reduced invertebrate predation; however, this effect is unlikely to result in much variation in survival of pupae on the forest floor.

Because bark and ambrosia beetles fly during their dispersal and host location processes, their flight height is important for assessing their host selection strategy. There is no consensus regarding the height of their dispersal flight in forests, and their method of approaching trees is unclear. This is also the case for Platypus quercivorus (Murayama) (Coleoptera: Platypodinae), which causes Japanese oak wilt by transporting a pathogenic fungus. To clarify the vertical distribution of the flying population of P. quercivorus inside the host tree canopy, interception traps were set up at heights of 1–9 m from the ground near the main trunk of eight host trees, Quercus serrata Thunberg (Fagaceae). Captured beetles were collected between July and October 2022. Hole-boring activities were observed on all trees during the season, and beetles were captured at all heights from 1 to 9 m. Beetle capture probability increased with a decrease in height, and the number of captured beetles increased with a decrease in distance from the main trunk. However, the trap design in this study could not capture individuals coming directly above and must be addressed to elucidate their method of approaching their host plant.

I review the history of forest tent caterpillar, Malacosoma disstria (Hübner) (Lepidoptera: Lasiocampidae), occurrence from 1938 to 2001 throughout Canada, with emphasis on the insect’s impact on tree mortality. I show that forest tent caterpillar routinely kills a portion of its host tree population during outbreaks. Although the proportion killed is typically small, there are some unusual conditions during which the foliage grazer can precipitate large-scale host forest declines. These decline episodes are the result of a spatially complex pattern of outbreak spread whereby successive cycles occur asynchronously enough that there is a zone of overlap where the two cycles occur in rapid succession, leading to three to six years of defoliation, triggering a nonlinear mortality response that endures through time. One of these “cycles” is typically amplified locally to an intensity that is anomalously high and nonrecurring. Defoliation events that are periodic in aggregate may thus give rise to patterns of insect-caused forest decline that are episodic. These decline events have been shifting northwards over time and have been growing in extent. The dynamics of outbreak occurrence appears to be a complex result of interacting top–down and bottom–up forces, making it challenging to predict in advance whether or not any given outbreak will exceed the threshold required to precipitate large-scale mortality.

Streams draining the Cypress Hills support unique and understudied macroinvertebrate communities in Saskatchewan, Canada. Here, we report the discovery of a species of caddisfly new to the Cypress Hills and Saskatchewan, Neophylax splendens Denning (Trichoptera: Thremmatidae). Larvae were collected early in May 2012, and are found to enter pre-pupal diapause in mid-June until mid-September. Larvae were identified as N. splendens by morphological characters and verified with genetic analysis. Its occurrence strengthens the biogeographical link between the montane regions in British Columbia, Canada and Utah, United States of America with the southwest corner of Saskatchewan. This study highlights the importance of seasonal sampling, resolute species level identifications in biological surveys and the use of genetic analyses to obtain this level of identification.

Identifying pests associated with novel crops is important for forecasting impacts on their production and determining if they could be reservoirs of pests moving over onto cash crops. We carried out preliminary pest surveys in two bioenergy crops, carinata (Brassica carinata Alexander Braun (Brassicaceae)) and camelina (Camelina sativa (Linnaeus) Crantz (Brassicaceae)), and a cover crop mix under evaluation to replace fallow in rotations with wheat. Insect pests were sampled in each of the three crops over two years. Crucifer flea beetles, Phyllotreta cruciferae Goeze (Coleoptera: Chrysomelidae), dominated the pest complex associated with carinata and the cover crop mix, comprising more than 70% of the insects sampled. In contrast, the pest complex associated with camelina was dominated (40–91%) by generalist Lygus spp. (Heteroptera: Miridae). Crucifer flea beetles were 200–1000 times more abundant in carinata than in camelina, suggesting that they could be a serious pest of carinata. Camelina, in contrast, appears less likely to be attacked by, or serve as a reservoir for, crucifer flea beetles. Future work to assess feeding damage and population buildup of pests in these crops is needed to determine impacts on their production and the extent to which they may be reservoirs of canola pests over broader spatial scales.

In June, 1938, I was able to spend eight days at the Public Museum of Quebec studying the Provancher collection of Ichneumonidae. Mr. Pierre-Georges Roy (Director of the Museum), Mr. Paul Rainville (Assistant Director), and Mr. Noel-M. Comeau (Curator of Insects), were very cordial and gave me facilities and help that made it possible to accomplish much more than could otherwise have been done.

Alternative chambers are used in laboratory studies of insect behaviour to determine responses to divergent pairs of temperatures, humidities, or light intensities. Theoretically, they provide an efficient means of presenting two different uniform intensities of a physical factor in equal areas that are separated only by a narrow, central boundary zone. In practice. however, only dark-light chambers approach this theoretical ideal. Jn temperature or humidity chambers, the boundary gradient often varies in width and steepness at different points, and the two halves may acquire unpredictably vagrant gradients which change in slope and extent with passing time.

The genus Frontiniella Townsend is transferred from the Eryciini to the Goniini, based on the production of microtype eggs in adult females. Frontiniella is known only from the Nearctic Region and the northern extreme of the Neotropical Region. Eufrontina Brooks is newly synonymized with Frontiniella and all species formerly placed in that genus are transferred to Frontiniella. Frontiniella is hypothesized to be monophyletic based on two derived character states: long hairs on the male surstylus, and elongate posterior spiracles on the puparium. Two species groups are recognized, one with six species and the other with four: the parancilla-group with F. parancilla Townsend, F. incarcerata sp.nov. (type-locality Hwy. 366, Graham Co., Arizona, USA), F. spectabilis (Aldrich) (new combination), F. surstylata sp.nov. (type-locality near Olustee, Florida, USA), F. jorgenseni sp.nov. (type-locality 20 miles northwest of Kenna, New Mexico, USA), and F. ethniae (Brooks) (new combination); and the festinans-group with F. festinans (Aldrich and Webber), F. apache sp.nov. (type-locality Sulphur Draw, Chiricahua Mts., Arizona, USA), F. mitis (Curran), and F. regilla (Reinhard). This revision includes a key to the 10 known species of Frontiniella, a description of each species (including puparium where known), maps of species distributions, an annotated list of hosts (including corrections to previously published records and additions from material examined), and illustrations of taxonomically useful features.

Spruce budworm, Choristoneurafumiferana (Clemens) (Lepidoptera: Tortricidae), larvae can cause extensive defoliation in balsam fir (Abies balsamea [Linnaeus] Miller) and exhibit high temporal and spatial variability in individual behaviour. We gathered field data to determine the influence of daily and hourly variation in abiotic conditions on daytime activity patterns of late-instar budworm larvae on balsam fir. In both years of our study, less than 10% of larvae were observed feeding during the daytime. Most larvae observed were either resting, spinning silk, or roaming, although the proportion of individuals engaged in each activity varied between years, with more larvae in the first year roaming (48%) and in the second year either resting (38%) or spinning silk (42%). Daily and hourly variation in abiotic conditions had a limited influence on activity patterns. Our results indicate that in nature, mid- to late-instar budworm larvae maintain fairly consistent activity patterns across a wide range of abiotic conditions. We suggest that site-specific conditions such as variation in host-plant quality and/or budworm population density may be more important than weather in determining the relative frequencies of different larval activities in space and time.

The Nearctic species of the genus Homaspis Foerster, parasites of various species of sawflies on coniferous and deciduous trees and shrubs, were revised. There are 10 species of which seven were described as new. These were placed in three species groups as follows: the areolatus group including H. areolatus and H. petiolatus spp.nov.; the cristatus group including H. cristatus and H. pectinatus spp.nov.; and the interruptus group, including H. interruptus (Provancher), H. slossonae Cushman, H. brevis sp.nov., H. cephalciae sp.nov., H. albipes Davis, and H. cavatus sp.nov. Relationships of the species groups were discussed.

Pseudoscorpions are microarthropods that are distributed from the equator to beyond the Arctic circle. Wyochernes asiaticus (Arachnida: Pseudoscorpiones: Chernetidae) is the northernmost species of pseudoscorpion and is broadly distributed in Beringia, an Arctic and sub-Arctic region that remained unglaciated during the last glacial maximum. Wyochernes asiaticus is anoxia tolerant and has moderate cold tolerance, but nothing is known about the molecular basis of their survival in Canadian polar environments. We de novo assembled and characterised the transcriptome of W. asiaticus collected from the Yukon Territory in northwestern Canada. We assembled an approximately 62.6-million base-pair transcriptome with a mean contig length of 1277, which was 76% complete, according to a benchmark universal single copy orthologue (BUSCO) analysis. We identified 1100 transcripts encoding proteins associated with stress tolerance in these pseudoscorpions, including heat shock proteins, antioxidants, ubiquitination and proteosomal proteins, and sirtuins. We also identified transcripts encoding putative venom proteins. We highlight eight transcripts with high sequence similarity to sequences of venom proteins (ctenitoxins and agatoxins) described from other pseudoscorpions. Our study yields the first transcriptome of a Beringian arthropod, providing important sequence information that will allow future investigation of how W. asiaticus survives in Canadian polar environments.

The following contribution to our knowledge of the Ichneumoninae of the boreal parts of Canada and of Alaska is based mainly on material obtained by the Northern Insect Survey, which is a co-operative project of the Canada Department of Agriculture and the Defence Research Board, Canada Department of National Defence.

The contribution brings forward 12 new species and subspecies 3 of them being represented by both sexes, 9 by the female sex only. Some arctic species already named before or regarded as holarctic elements will be treated in a separate publication.

Enaphalodes rufulus (Haldeman) (red oak borer; Coleoptera: Cerambycidae) is a native wood borer that colonises and develops in oaks (Quercus Linnaeus; Fagaceae) across southeastern Canada and the eastern United States of America. It is rarely considered a pest because it normally occurs at low population density levels in stressed or dying oak trees. In the late 1990s and early 2000s there was a large, historically unique outbreak of E. rufulus in the Ozark mountains of Arkansas and Missouri, United States of America. This outbreak provided an opportunity to investigate within-tree spatial distribution of attacks during unusually high insect population levels. Fifty trees from northern Arkansas were felled and destructively sampled. The locations of attack sites by female E. rufulus were standardised across varying heights and diameters for comparison across trees. Attack sites showed a significant clustered pattern within trees. Attack sites were aggregated towards the lower and middle bole, and on the south-facing side of trees. This pattern has been seen in other insects, including wood borers, and is potentially related to differences in temperature. These patterns of ovipositional behaviour in outbreak situations have implications for E. rufulus resource partitioning and facultative intraguild predation among larvae.

The necrocolous Coleoptera (attracted to carrion) are important to maintain balance in insect communities and in the recycling of soil nutrients; however, there is scarce data on the species that occur in Agave tequilana Weber (Asparagaceae) fields. The diversity patterns of beetles (Coleoptera: Scarabaeidae, Silphidae, and Trogidae) dwelling in 2–4-year-old A. tequilana plots were established by sampling specimens from May to November 2016. In total, 5509 individuals of 23 species were collected. The highest species diversity was found in Magdalena Municipality, followed by the Arandas and Tequila municipalities (Jalisco, Mexico), with significant differences in abundance among municipalities and crop age. The variability in Magdalena and Tequila assemblages was associated with the temperature, while in Arandas it was attributed to the precipitation. The beetle species diversity, species replacement, and dominance in different municipalities are the result of changes in habitat, the interaction of environmental variables, distribution affinities of species, and agronomic practices in A. tequilana fields.