Immature stages of the uniquely phytophagous staphylinid, Himalusa thailandensis Pace, Klimaszewski, and Center, 2010 (Coleoptera: Staphylinidae: Aleocharinae) are described. Adults chew or scrape leaf surfaces while larvae bore into leaf petioles where they mature, and then drop to the ground to pupate in silken cocoons. Compared to other aleocharines, the larval body form is unusually compact and rotund, and may be an adaptation to living within the confines of plant tissue. Mandible and maxilla morphology is unique among known larval aleocharines in being robust and dentate, and we suggest this is adaptive for scraping and squeezing plant tissue. The larval defensive gland is ribbed and gland sac ducts are kinked and apically bifid. We suggest that H. thailandensis may share this derived gland morphology with Autaliini, Bolitocharina, Gyrophaenina, Homalotina, Leptusina, and Silusina of Homalotini, and possibly Liparocephalini. The morphology and ecology detailed here for H. thailandensis is the first comprehensive description of immature stages among aleocharines where adults feed externally on plants.

Forest tent caterpillar (Malacosoma disstria Hübner; Lepidoptera: Lasiocampidae) is a widely distributed defoliator that undergoes intermittent outbreaks. It overwinters as pharate larvae within egg bands, is univoltine, and experiences low winter temperatures in its northern range. Little is known about how low temperatures affect winter survival and cold tolerances, their cold tolerance strategy, or how cold tolerances may vary over time and among populations. We evaluated supercooling points (SCPs) from four populations of M. disstria eggs collected along a 552 km latitudinal gradient from southern Wisconsin to northern Minnesota, United States of America. To test for potential effects of winter environment, we also administered three overwintering regimes (Madison, Wisconsin; Cloquet, Minnesota; Ely, Minnesota). Supercooling points were recorded in November, February, and March of 2011–2012. Supercooling points varied with maternal source (egg band), time of winter season, population source, and overwintering treatment. Means ranged from −26.8 °C (±0.5 °C) to −40.3 °C (±0.3 °C), accordingly. In a separate laboratory experiment, 89% of pharate larvae held at −20 °C (18.3 °C above coolest mean SCP) survived, but none held at −45 °C (6.7 °C below lowest mean SCP) survived. This relatively high degree of cold tolerance in its overwintering stage, due to freeze avoidance, may partially explain survival patterns and limits of overwintering M. disstria in northern populations.

Five species of woodpeckers (Piciformes: Picidae) in Manitoba, Canada were examined for chewing lice (Phthiraptera: Amblycera and Ischnocera): downy woodpecker (DOWO) (Picoides pubescens (Linnaeus), n=56), hairy woodpecker (HAWO) (Picoides villosus (Linnaeus), n=32), pileated woodpecker (PIWO) (Dryocopus pileatus (Linnaeus), n=12), northern flicker (NOFL) (Colaptes auratus (Linnaeus), n=223), and yellow-bellied sapsucker (YBSA) (Sphyrapicus varius (Linnaeus), n=192). Seven species of lice were collected (total number=40 613): Menacanthus pici (Denny) from all species of woodpeckers, Brueelia straminea (Denny) from both species of Picoides Lacépède, Penenirmus jungens (Kellogg) from northern flicker, Penenirmus auritus (Scopoli) from all species of woodpeckers examined except northern flickers, Picicola porisma Dalgleish from northern flickers, Picicola snodgrassi (Kellogg) from both species of Picoides, and Picicola marginatulus (Harrison) from pileated woodpeckers. Prevalence for total louse infestation ranged from 32.3% to 85.7% (NOFL>YBSA>PIWO>DOWO>HAWO). Mean intensity for total lice ranged from 29.2 to 232.4 (PIWO>NOFL>HAWO>YBSA>DOWO). Infestation parameters for each louse/host combination are provided. Distribution of louse infestations was highly aggregated. In all louse/host combinations, either females were more prevalent than males or there was no significant deviation from 50:50. There was a tendency for louse species to co-occur on the same host specimen.

We collected naturally infested Pinus resinosa Aiton (Pinaceae) and P. sylvestris Linnaeus to investigate phenological patterns and quantify parasitism by a suite of native hymenopteran parasitoids on two woodwasps (Hymenoptera: Siricidae): the invading non-native European woodwasp, Sirex noctilio Fabricius, and a co-colonising native, S. nigricornis Fabricius. We sampled a total of 76 trees from two field sites in 2010 and seven sites in 2011. In raw abundance, S. noctilio outnumbered S. nigricornis by 2:1 in 2010 and by 7.5:1 in 2011. We collected the egg/early instar parasitoid, Ibalia leucospoides ensiger Norton (Hymenoptera: Ibaliidae); four species of Rhyssinae (Hymenoptera: Ichneumonidae) late larval parasitoids; and Pseudorhyssa nigricornis (Ratzeburg) (Hymenoptera: Ichneumonidae), a cleptoparasitoid of rhyssines. Variation in siricid and parasitoid species assemblage and abundance was explained primarily by site, with tree-level factors playing a secondary role. Parasitism was significantly lower in P. sylvestris (13.6%±4.1 SE), a naturalised pine from Europe, than in the native P. resinosa (28.5%±5.0). Total parasitism was 27.6%±5.0 in 2010 and 20.9%±4.7 in 2011. This study represents the most robust analysis of the diverse woodwasp and parasitoid assemblage infesting pines in North America.

The invasive woodwasp Sirex noctilio Fabricius (Hymenoptera: Siricidae) is obligately associated with the symbiotic white rot fungus Amylostereum areolatum (Chaillet ex Fries) Boidin (Basidiomycota: Amylosteraceae), and shows positive chemotaxis to volatiles emitted by this symbiont. After introduction to North America, S. noctilio was collected carrying another fungus species Amylostereum chailletii (Persoon) Boidin, used symbiotically by native North American Sirex Linnaeus. We conducted flight behaviour studies in a walk-in flight tunnel to evaluate specificity of the attraction of mated and unmated S. noctilio to its primary symbiont, A. areolatum, versus the alternative symbiont, A. chailletii. Fewer unmated than mated S. noctilio females responded to either of the fungi. Unmated females showed no landing preference but mated S. noctilio females were attracted to A. areolatum although avoidance of A. chailletii was not complete. Chemical analysis demonstrated major differences in the volatile profiles of the two fungal species. Sesquiterpenes dominated the A. areolatum samples, whereas only two aromatic volatiles were consistently present in the native A. chailletii.

Blueberry fruit fly, Rhagoletis mendax Curran (Diptera: Tephritidae), females deposit a host-marking pheromone (HMP) on the surface of fruit immediately after oviposition that deters oviposition by female conspecifics. We collected this HMP from artificial oviposition devices and faeces. In subsequent two-choice bioassays, gravid females showed a strong preference for untreated oviposition devices as compared to those treated with extracts from either of these two sources. The methods described for collecting HMP of R. mendax will be useful for its eventual identification and synthesis, with potential applications in R. mendax management.

Whitebark pine, Pinus albicaulis Engelmann (Pinaceae), a foundational species of North American subalpine ecosystems, is endangered across its range and continued decline is inevitable. Little is known about the invertebrate fauna associated with this species which, if specific to whitebark pine, may also be threatened or endangered. We compared the composition of saproxylic beetle assemblages associated with whitebark pine and co-occurring lodgepole pine, Pinus contorta latifolia (Engelmann) Critchfield (Pinaceae), recently killed by mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), in subalpine forests in Alberta, Canada. Redundancy and rarefaction analyses revealed that beetle assemblage composition was influenced by snag class (i.e., time since death) but differed little among the two pine species within snag classes. However, a subset of the assemblage known to be associated with the MPB differed significantly in composition between the two pines. No common species were exclusively associated with whitebark pines; however, seven species were rarely collected only on whitebark pine. With the possible exception of these rare species, felling and burning infested whitebark pines to control the MPB will not likely endanger saproxylic beetles associated with this tree.

Discovery of the non-native Anoplophora glabripennis Motschulsky (Coleoptera: Cerambycidae) in Ontario, Canada, in 2003 led to the implementation of an eradication programme. The plan consisted of removing all infested trees and all trees belonging to a genus considered suitable for complete development of this wood-borer that were found within 400 m of an infested tree; however, many of the trees within that 400 m belonged to genera for which suitability for development of A. glabripennis was questionable or unknown. We visually inspected over 3000 such trees annually for the three years following removal of infested trees. All but one tree were unattacked: an ash (Fraxinus excelsior Linnaeus (Oleaceae)) tree had signs of oviposition and early-instar development, but not of adult emergence. Before that survey, we had found only one other species with questionable suitability, a little leaf linden (Tilia cordata Miller (Malvaceae)) that had many signs of oviposition, but no evidence of full development, suggesting resistance to A. glabripennis. Both of these trees were within 200 m of the most heavily infested maple (Acer platanoides Linnaeus (Sapindaceae)) tree found in that infestation, suggesting that colonisation of trees with questionable or unknown suitability might occur mostly where population pressure is high.

Mechanistic species niche models were used to map the seasonal spatio-temporal dynamics of biological control pressure. Future climate scenarios were applied to these models to identify potential future trends in the patterns of biological control pressure through space and time during an annual seasonal cycle. Peristenus digoneutis Loan (Hymenoptera: Braconidae) is a parasitoid of Lygus Hahn (Hemiptera: Miridae) species, important pests of glasshouse and field crops throughout Europe and North America. Consistent with theoretical expectations, the modelled potential range of P. digoneutis expanded polewards and contracted from its southern temperature range limits. However, its distribution did not change consistently across continents or countries. Locations near the outer limits of the current modelled distribution were more sensitive to changes in future climates than locations near the central core. Weekly climate suitability and stress maps were developed to provide insight into seasonal adjustments that accompany changes in the potential range of pest species and their natural enemies. Climate change may increase the number of Lygus generations in western Canada allowing P. digoneutis to establish in areas, where biological control attempts had failed in the past.

The pea leaf weevil, Sitona lineatus (Linnaeus) (Coleoptera: Curculionidae), is an important pest of field peas, Pisum sativum Linnaeus (Fabaceae), and faba beans, Vicia faba Linnaeus (Fabaceae), that has recently become established in the Prairie Provinces of Canada. Male pea leaf weevils produce an aggregation pheromone, 4-methyl-3,5-heptanedione, in the spring when overwintered weevils migrate to fields to feed and mate. The current study tests the attractiveness of the aggregation pheromone with and without synthetic bean volatiles to pea leaf weevils in the spring and in the fall when weevils seek perennial legumes to feed and overwinter. Modified Leggett traps similar to those used in Europe did not retain weevils in this study. Aggregation pheromone-baited pitfall traps caught male and female weevils in the spring and fall. Weevils were not attracted to traps baited with three bean volatiles, (Z)-3-hexen-1-yl acetate, (Z)-3-hexen-1-ol, and linalool. Bean volatiles did enhance response to pheromone, but only in the fall. Weevils were captured in most semiochemical-baited traps in a 1:1 sex ratio, but female-biased catch in control traps might indicate greater activity of females in the trap vicinity. This study lays the groundwork for semiochemical-based monitoring to detect pea leaf weevil spread in the Prairie Provinces.

Plant growth and insect resistance characteristics were determined for two Brassica napus Linnaeus (Brassicaceae) lines, AtGL3+ and K-5-8, developed for enhanced trichome densities relative to their parental cultivar Westar. In the field, both transgenic lines had glabrous cotyledons that curled upwards at emergence but flattened with time, and young leaves with elevated trichome density. Flea beetle (Phyllotreta cruciferae (Goeze) and Phyllotreta striolata (Fabricius); Coleoptera: Chrysomelidae) feeding was reduced on true leaves of both lines by 30–50% compared with insecticide-free Westar. Flea beetle feeding levels on cotyledons of the two hairy-leaved lines were lower than on unprotected Westar and similar to those seen on insecticide-treated Westar. Antixenosis and antibiosis resistance was observed when diamondback moths (Plutella xylostella (Linnaeus); Lepidoptera: Plutellidae) interacted with the hairy AtGL3+ and K-5-8 lines in the laboratory. Although the numbers of eggs laid by female diamondback moths on the transformed lines were similar to or higher than on Westar, in feeding bioassays larvae moved off AtGL3+ plants and larval feeding injury decreased on the transformed lines compared with Westar leaves. No agronomic or seed yield penalties were found for plants of K-5-8. These data highlight the utility of manipulating trichome regulatory genes to increase plant resistance against brassicaceous insect pests.

Euxestonotus error (Fitch) (Hymenoptera: Platygastridae) is considered part of the natural enemy complex of the wheat midge Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae). Although previously reported in the United States of America, there is no record for this species outside the state of New York since 1865. A survey conducted in the summer of 2015 revealed that E. error is present in northwestern Montana and is likely playing a role in the suppression of wheat midge populations.