The immature stages of Neotephritis finalis (Loew.) are described and figured. Notes on the biology and the larval feeding damage to cultivated sunflowers also are given.

Male mullein bugs, Campylomma verbasci (Meyer), were attracted in field experiments in the Okanagan Valley of British Columbia to traps baited with females, extracts of crushed females, or Porapak Q-captured volatiles from females on common mullein, Verbascum thapsus L. Extracts from the female head and thorax attracted more males than did abdominal extracts. Traps baited with C. verbasci of both sexes caged together were not attractive. Analysis by coupled gas chromatography – mass spectrometry revealed n-butyl butyrate and n-hexyl butyrate in female extracts and captured volatiles, but only the latter compound in male extracts. However, these esters were unattractive, either alone or combined. We suggest that Porapak Q-captured volatiles could be used in pheromone isolation, and that pheromone-baited traps have promise in monitoring populations of C. verbasci.

The braconid parasitoid Meteorus trachynotus Vier. was found in overwintered larvae of the obliquebanded leafroller, Choristoneura rosaceana (Harr.), on foliage of a variety of deciduous species, well before the parasitoid’s attack on the spruce budworm, Choristoneura fumiferana (Clem.). In the spring, percentage parasitism of C. rosaceana by M. trachynotus was 8.0 and 18.8% in 1986 and 1987, respectively. Maximum parasitism on C. fumiferana (35 and 4% in 1986 and 1987, respectively) was reached in late June, at a time when over 50% of M. trachynotus cocoons found on deciduous vegetation had emerged. Twenty days later, parasitoids produced on C. fumiferana reached 50% adult emergence. The catches of adult parasitoids on sticky traps placed on deciduous trees and on conifers showed two periods of adult activity. Based on the sex ratio of captured parasitoids, male M. trachynotus were active at emergence sites, whereas females were found mostly in the habitats of available hosts. The phenology of C. rosaceana was observed in 1987. As indicated by light-trap captures, males fly sooner than females. Eggs were laid in July, and so the early larval stages were available to female M. trachynotus as overwintering hosts. Several parasitoids common to C. rosaceana and C. fumiferana were identified.

A gallery system and the mature larva of Dendroctonus punctatus LeConte are described from white spruce in Montana. The gallery is allied to that of the Eurasian D. micans (Kugelann) but the larva differs particularly in having a sclerotized area on the eighth abdominal tergum that is lacking in D. micans. Similar native species are D. murrayanae Hopkins, which infests pines, and D. rufipennis (Kirby), which infests spruces. A key and diagnostic characters are presented for identifying D. punctatus larvae.

Geina sheppardi sp.nov., a grape-feeding platyptiliine (Pterophoridae), is described. Its distribution, biology, and diagnostic features are discussed and related to those of two other partly sympatric and morphologically similar species of grape-feeding Platyptiliinae, Sphenarches Ontario (McDunnough) and Geina periscelidactyla (Fitch). A lectotype is designated for the latter.

Two bioassay methods using leaf discs and Petri dishes as the treated medium were compared. Resistance levels were approximately 11-fold with the leaf disc method and 7-fold using the Petri dish assay. Comparisons of the two methods on six wild populations indicated that the Petri dish assay was more sensitive in identifying low frequencies of resistance. Advantages of the Petri dish assay over the previously used leaf disc method for rapid, field-type surveys are discussed.

Surveys of populations from the Simcoe and Niagara areas, using the Petri dish assay, indicated resistance to dicofol in 11 of 22 samples. Resistance was generally correlated with sites where dicofol had been used at least once a year for 2–3 consecutive years. The data indicate a resurgence of dicofol resistance since 1984 when resistance was detected at 4% of the surveyed sites.

Larval performance and adult size of Chrysomela knabi Brown varied with host quality and species. Beetles reared on a low moisture diet of Salix humilis Marsh. or a novel host, S. nigra Marsh., showed reduced growth rates, survival, and adult size compared with performance on the local host, S. humilis, at high moisture. For all performance variables, beetles were least successful on the novel host. Development (hatch to pupation) was 1.2 and 3.9 days faster on the high moisture diet than on the low moisture diet or novel host, respectively. Survival (hatch to pupation) was 8 and 20% higher on the local host (high moisture) than on the low moisture diet and novel host, respectively. Weight and elytral length of newly eclosed adults showed these same trends.

Aspects of the biology of Cystiphora sonchi (Bremi) (Diptera: Cecidomyiidae) were investigated and releases were made on perennial sow-thistle (Sonchus arvensis L.) (Compositae) in six provinces of Canada. Fecundity, determined by dissection of newly emerged females, averaged 86.2 eggs. Cystiphora sonchi became established in Alberta, Saskatchewan, Manitoba, and Nova Scotia, and produced three generations at Vegreville, Alberta. In fall, mature larvae enter the soil, and most can pupate in temperatures of 4 °C. The gall fly thrives in shady and sunny locations. Cattle caused considerable fly mortality by feeding on galled leaves of perennial sow-thistle. Extremely dry or moist soils reduced the number of adults that emerged from pupation and extremely moist soils increased the lengths of the pupation periods. Flooding caused greater mortality of pupae than of larvae but 2% of the larvae survived flooding up to 8 weeks.

The lodgepole terminal weevil, Pissodes terminalis Hopping (Coleoptera: Curculionidae), is widely distributed in western North America on three races of lodgepole pine (Pinus contorta Dougl.), as well as jack pine (P. banksiana Lamb.), Bishop pine (P. muricata D. Don.), and Monterey pine (P. radiata D. Don.).

Three types of life cycle, one with three subtypes, are identified. In the univoltine type 1 cycle, adults emerge from attacked leaders in the fall, overwinter probably in the ground, and re-emerge in the spring to lay eggs in elongating leaders. Larval and pupal development is completed by early fall. The univoltine type 2 life cycle is similar, except that overwintering takes place in leaders; fourth-instar larvae overwinter in type 2A, pupae in type 2B, and adults in type 2C. The type 3 life cycle takes 2 years to complete, with the first winter being passed as a third-instar larva in the leader and the second as an adult, probably in the ground. The type 1 life cycle is most common at altitudes < 2000 m and the type 3 life cycle at altitudes over ca. 2500 m; all types may be found at altitudes of 2000–2500 m.

Economic injury levels and economic thresholds for nymphs of Lygocoris communis (Knight) were defined in apple orchards, using the beating technique. These were determined with 1987 apple market value and chemical control costs. Economic thresholds were established, assuming a 24-h period required for control implementation. Highly significant relationships were found between the damage at harvest and the captures of young nymphs of L. communis. The economic injury levels ranged from 0.4 to 5.8 young nymphs per sample unit depending on the sample unit and insecticide used.

The joint action of permethrin and Bacillus thuringiensis var. kurstaki Berliner (B.t.), Autographa californica (Speyer) nuclear polyhedrosis virus (ACNPV), or Artogeia (= Pieris) rapae (L.) granulosis virus (ARGV) fed as mixtures to larvae of Trichoplusia ni (Hübner) or A. rapae in laboratory bioassys differed with the host insect, the components, and the concentrations of the components. Permethrin interfered with the activity of ACNPV and ARGV in most of the mixtures, particularly at low concentrations of the latter virus but mortality by mixtures of mid-range (approximately LC50 if fed alone) concentrations of permethrin and of ACNPV exceeded the mortality expected by the components acting independently. Concentrations of permethrin in the middle of the dosage range enhanced the effect of B.t. against T. ni resulting in mortality that exceeded the expected mortality but mortality of A. rapae larvae fed most permethrin–B.t. mixtures was less than expected.

Nematode parasites of bark beetles are taxonomically diverse, and may, in some cases, cause serious pathological and behavioural changes in their hosts (Kaya 1984). Their potential as biological control agents has long been recognized, but to date there is a shortage of elementary information on host-parasite interactions. Though the effects of superparasitism and subsequent crowding on the parasite have been studied for some mermithids (Petersen 1972) and steinernematids (Sandner and Stanuszek 1971), no such observations have been reported for bark beetle parasites. During a survey of nematode parasites of bark beetles in Manitoba, we encountered two examples where nematodes were detrimentally affected at the higher infection rates observed. It was our objective, therefore, to examine the relationship between intensity of infection, and impact on growth and reproduction of the parasites.

Glossina morsitans submorsitans Newstead has two pairs of autosomes, a pair of sex chromosomes (males are heterogametic), and from two to seven supernumerary (=B) chromosomes (Southern and Pel1 1973). The only information allowing assignment of loci to linkage groups in this subspecies is that electrophoretic evidence suggests that five polymorphic loci, including Est-2 and Mdh, are autosomal (Gooding 1984a), and breeding experiments indicate that sex ratio distortion, favoring production of females, is due to an X chromosome-linked factor (Gooding 1986).

During a study on the litter arthropods of the natural forests of southern Quebec, Mymarommatidae specimens were found near Lachute, northwest of Montreal. Fewer than 200 specimens of Mymarommatidae have been collected throughout the world (Huber 1987); there are only nine species, all in the genus Palaeomymar Meunier (Yoshimoto 1984). Morphologically, the insects are characterized by a two-segmented abdominal petiole and atrophied posterior wings attached to the anal margin of entirely reticulated anterior wings (Huber 1987). Their biology is still unknown (J.T. Huber, pers. comm.), although it is thought that they may be insect egg parasites (Yoshimoto 1984). Yoshimoto (1984) included the Mymarommatidae in the Chalcidoidea. However, Gibson (1986) proposed not to include them in a superfamily until the phyletic relationships of the Terebrantes are better defined.

Predators of the spruce budworm, Choristoneura fumijerana (Clem.), include both invertebrates and vertebrates (Jennings and Crawford 1985). Birds are the best known and most extensively studied vertebrate predators, but because of their arboreal and omnivorous feeding habits, the deer mouse, Peromyscus maniculatus (Bangs), and the red squirrel, Tamiasciurus hudsonicus (Bangs), often are implicated as potential predators of budworm larvae and pupae (Morris et al. 1958; Morris 1963; Otvos 1981; Welsh 1983). In laboratory feeding trials, W.F. Chesire estimated that red squirrels had a mean food capacity of 600–700 mature larvae or pupae of the spruce budworm per day (Morris 1963). R.T. Mitchell examined the stomach contents of 25 red squirrels collected during a major spruce budworm outbreak in northern Maine (Dowden et al. 1953); he found that spruce budworms made up 51% of their total food. On the basis of these results, Dowden et al. (1953) estimated that a red squirrel could eat 400–500 larvae per day.