The bee species described and identified by Léon Provancher are reviewed. From 1882–1896, Provancher published accounts of 179 bee species from North America, which represent 145 currently recognised species. He proposed 67 new names, 21 of which are here considered valid; five species epithets proposed by Provancher were junior homonyms.

The following are considered new junior synonyms of Provancher species: Andrena macrocephala Cockerell under Andrena nigripes Provancher; Pseudopanurgus nebrascensis (Crawford) under Pseudopanurgus aestivalis (Provancher); Lasioglossum timberlakei McGinley under Lasioglossum californicum (Provancher); Osmia kenoyeri Cockerell under Osmia tarsata Provancher. Additional new synonymies made here include: Halictus distinguendus Dalla Torre under Lasioglossum coriaceum (Smith); Osmia parva Provancher under Osmia atriventris Cresson; Stelis plena (Provancher) under Stelis lateralis Cresson; Coelioxys tristis Provancher under Coelioxys sodalis Cresson; Diadasia tricincta Provancher under Eucera actuosa (Cresson).

Lectotypes for 60 of Provancher's bee species are here designated, but type material for eight other species were not found. The taxonomic placement of Calliopsis quadrilineata Provancher, Calliopsis interrupta Provancher, Hoplitis alboscopata (Provancher), Hoplitis imperfecta (Provancher), and Diadasia albovestita Provancher within the bee fauna of North America remain unclear, and are here declared nomina oblita.

The Hesperempis genus group is revised. The group includes Dryodromia Rondani and Hesperempis Melander, with Melanderalus Özdikem and Başar and Toreus Melander newly synonymised with Hesperempis, newsynonymy. Dryodromia includes D. testacea Rondani from the western Palaearctic and D. yunnanica Cumming and Saigusa new species from southwestern China. Hesperempis includes H. anatolica Cumming and Brooks new species, H. mabelae (Melander), H. neomexicana (Melander) newcombination, H. sanduca Melander, and H. vespera Cumming and Brooks new species from the Nearctic Region, as well as H. melina Cumming and Saigusa new species, H. nipponica Cumming and Saigusa new species, and H. sibirica Shamshev from the Palaearctic Region. A key to the two genera and 10 species is provided, and a cladistic analysis is presented. A new interpretation of the homologies of the male terminalia is proposed for this lineage, and the phylogenetic relationships and zoogeographic history of the group are discussed.

Complex subsociality involving guarding, progressive provisioning, and trophic egg production behaviours in herbivorous Hemiptera is known in only a few genera in the Cydnidae subfamily Sehirinae and in Parastrachiidae. Because progressive provisioning and trophic egg production are apparently specific to these closely related species, phylogenetically it seems likely that the behaviours emerged once in the common ancestor of this clade. However, the scarcity of information on species in the clade precludes any reliable exploration of this hypothesis. To ameliorate this situation, it is necessary to accumulate additional information for as many related species as possible. To this end, we first targeted Japanese representatives of the genus Adomerus Mulsant and Rey (Hemiptera: Cydnidae), three species of which are distributed in Japan. Complex subsocial behaviours in two of these species, Adomerus triguttulus (Motschulsky) and Adomerus variegatus (Signoret), have been well characterised and analysed. The third Japanese species, Adomerus rotundus (Hsiao), was identified to display complex maternal care, but, with the exception of egg hatch synchronisation, parental behaviours have not been characterised. In this study, we examined the parental behaviours of A. rotundus. Additional investigations on subsocial behaviours, in addition to morphological and molecular analyses, should gradually clarify whether the complex subsociality represents a homologous or convergent adaptation.

Nutritional variability in resources may cause differential mortality between sexes resulting in biased sex ratios. If males and females differ in fitness, then mortality of the more sensitive sex can cause a bias in sex ratios, and can stimulate dispersion of males. We reared three generations of spruce budworm (Choristoneura fumiferana (Clemens); Lepidoptera: Tortricidae) on two artificial diets: a “normal” diet that provided all nutritional requirements for development and a “stress” diet (deficient in sugars and slightly higher in nitrogen), that simulated deterioration of food quality during outbreak conditions and had a detrimental impact on larval survival, development and growth. We tested the effects of continued nutritional stress on the sex ratio of pupae and adults. We found biased sex ratios in favour of males related to diet. Low quality food resulted in fewer females. This distortion was observed from the second generation onward, with a lower percentage of females reaching the pupal and adult stage. These results provide evidence that nutritional variation causes differential mortality between sexes, suggesting that females are more sensitive to nutritional stress. This is the first study that demonstrates sex ratio distortion due to nutritional selection pressure in spruce budworm. Our results indicate the importance of studying sex ratio distortion of spruce budworm in outbreak conditions.

Surveys were conducted in Ontario and Québec, Canada to determine the parasitoid communities associated with Ceutorhynchus Germar (Coleoptera: Curculionidae) weevil species that are potential nontarget hosts of candidate biological control agents of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham). New host plant associations are documented for Ceutorhynchus americanus Buchanan, Ceutorhynchus neglectus Blatchley, and Ceutorhynchus omissus Fall. More than 18 species of Chalcidoidea (Hymenoptera) were associated with six Ceutorhynchus species reared from siliques and stems of Brassicaceae plants. Silique-feeding Ceutorhynchus species supported a more diverse parasitoid community than stem-feeding or root crown-feeding species. The major components of the parasitoid assemblage of the native C. neglectus included Mesopolobus gemellus Baur and Muller, Mesopolobus moryoides Gibson, Trichomalus lucidus (Walker) (Hymenoptera: Pteromalidae) and a cryptic species complex previously reported as Necremnus tidius (Walker) (Hymenoptera: Eulophidae). These species, plus Trimeromicrus maculatus Gahan (Hymenoptera: Pteromalidae) were the main parasitoids attacking the native C. omissus. The major parasitoids associated with the accidently introduced Ceutorhynchus erysimi (Fabricius) and Ceutorhynchus typhae (Herbst) included T. maculatus, the N. tidius species complex, M. gemellus, and M. moryoides. Trichomalus perfectus (Walker) (Hymenoptera: Pteromalidae), a major parasitoid of C. obstrictus in Europe, is an accidental introduction first reared in Canada from that host in 2009 and first collected from C. omissus in 2011. Mesopolobus gemellus is shown to have a broad host range. These findings highlight the need for a cautious approach before introducing new biological control agents.

The objective of this study was to compare the honey yields of groups of honey bee (Hymenoptera: Apidae) colonies with high and low infestation rates of the mite Varroa destructor Anderson and Trueman (Acari: Varroidae). More than 150 colonies were screened for mite fall in early spring and again 16 weeks later. The 10 colonies with the lowest rates (L) and the 10 colonies with the highest rates (H) of mite population growth were selected. These 20 colonies were evaluated for mite infestation in adult bees and honey production. Adult bee infestation in the colonies of the H group was significantly higher than in the colonies of the L group. Additionally, H and L colonies differed significantly for honey production. L colonies produced 28.91 ± 2.34 kg of honey per hive versus 18.49 ± 0.77 kg for the group of H colonies. Furthermore, the mite infestation level of colonies measured as mite fall or as number of mites per 100 bees, was significantly correlated with honey production (r = −0.62, P < 0.05 and r = −0.76, P < 0.01, respectively). These results indicate that varroa mite populations significantly reduce honey yields in honey bee colonies in eastern Canada.