Adult males were reared from larvae of the type previously associated with Anepeorus. These adult males key to and fit the description of Heptagenia cruentata Walsh. Because the larvae are very different from those of other Heptagenia species, a new genus, Raptoheptagenia, is proposed for cruentata. Adult males of Raptoheptagenia differ from those of Heptagenia in the anastomosis of two or more crossveins in the stigmatic area of the forewing, and in the subequal lengths of the foretarsus and tibia.

Acanthomola pubescens, a new genus and species of Heptageniidae (Ephemeroptera), is described from larvae collected in Saskatchewan and Alberta. Acanthomola superficially resembles Bleptus, Epeorus, and Raptoheptagenia, but differs from these genera, and all other heptageniids, in the structure of the mandibles and maxillae. The molar area of the mandible is greatly reduced and bears only a few stout spines. The crown of the maxillary galea-lacinia is rounded and lacks setae near the apex. The apical segment of the maxillary palpus is long, slender, and bare. Generic and specific descriptions of the larva of A. pubescens, gen. nov., sp. no v., are given, along with biological notes. Acanthomola appears to be a very primitive heptageniid, related to Bleptus, Epeorus, and Ironodes. It is probably most closely related to Spinadis.

Adult flea beetles, Phyllotreta cruciferae (Goeze), P. striolata (F.), and Psylliodes punctulata Melsh., overwintering in the litter of a riverbank forest at Winnipeg, Manitoba, varied in density from about 1.4 million to 2.5 million beetles per hectare from 1979 to 1983. Phyllotreta cruciferae was the most abundant species (78–92%) and P. striolata next (6–22%) in litter samples collected in the late autumn, just before the ground froze. The distribution of beetles was highly aggregated (variance/mean ratio > 1.0) for P. cruciferae and P. striolata in years of high density but this ratio was 1.0 (random distribution) when densities were below 1.0 per square metre. Density was positively related to the amount of litter and increased from the edge to the center on the south side of the grove. On the north side, densities were highest at the edge of the grove. Survival in the litter during the autumn was generally lower and more variable than during the winter or spring periods. Survival in the litter during the 4 years ranged from 0.22 to 0.46 for P. cruciferae and from 0.31 to 0.83 for P. striolata. Temperature, through its effect on the time of emergence of adults in late summer and autumn, may affect their ability to survive the onset of cold weather.

Developmental times were determined at constant temperatures for egg–larval (prepupal) and egg–larval–adult (preadult) house flies in poultry manure. Developmental time decreased as temperature increased but declined at temperatures above 35°C. The average time from oviposition to pupation ranged from 26.8 days at 16°C to 5.2 days at 35°C, and the average time to adult emergence ranged from 43.1 to 8.8 days. Pupae were formed at 41°C, but no adults emerged above 38°C. The relationship between developmental rate and temperature was determined and used in a rate summation model to simulate prepupal and preadult developmental times in poultry manure, with manure bed temperature as input. The model was tested on the basis of developmental times determined in a poultry house during the fly-breeding season. The observed mean time to pupation under field temperatures ranged from 6.7 to 15.6 days, and adult emergence required from 12.5 to 27.1 days. Simulations were closest to the observed times when actual manure bed temperatures were used as input; however, soil temperatures obtained from a nearby weather station also provided satisfactory simulation results after an empirical correction was used.

An extensive collection of adult Capnia licina Jewett was made in the Mount Baker area, Washington, USA, and from this the previously unknown female is described and illustrated, and the male redescribed and reillustrated.

Circulifer tenellus (Baker) has a mean preoviposition period of 13.1, 8.2, 6.4, and 5.0 days when held at 20, 25, 28, and 32°C, respectively. The fecundity of C. tenellus averaged 105.0, 98.9, 115.7, and 196.9 eggs per female when held under the same temperatures, respectively. The longevity of the adult C. tenellus females when held under constant conditions of 20, 25, 28, and 32°C averaged 58.1, 52.7, 41.9, and 44.8 days, respectively. Fluctuating temperatures of 19–36°C under greenhouse conditions resulted in a mean preoviposition of 10.7 days and a fecundity rate of 163.4 eggs per female with females living an average of 96.3 days with a longevity range of 142 days.

Aerially applied Thuricide 48LV, Thuricide 64B, Futura XLV, and water-based formulations of Bacillus thuringiensis Berliner var. kurstaki (B.t.), were tested for effectiveness to control the hemlock looper, Lambdina fiscellaria fiscellaria (Guen.), in balsam fir, Abies balsamea (L.) Mill., stands. Thuricide 64B, applied twice at a dosage of 30 Billion International Units (BIU) per hectare in 1.78 L/ha, was the most effective, reducing the larval population by 100%.

A study conducted between 1982 and 1985 established the presence of a limited number of populations of Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), resistant to carbofuran in New Brunswick. Additional laboratory tests with two field-collected strains indicated that both were resistant to endosulfan; one strain also showed 43- and 37-fold levels of resistance to carbofuran and phosmet, respectively, and low-level (< 10-fold) resistance to permethrin, fenvalerate, disulfoton, and aldicarb. There has been no measurable spread of resistance.

Pissodes approximatus Hopkins (1911) is a junior subjective synonym of P. nemorensis Germar (1824). The conspecificity of these entities, traditionally considered distinct based only on distribution and slight morphological differences, is corroborated here with comparative studies of ecology, behavior, and morphology. When pheromone-baited traps were deployed during the spring (May–June) and fall (November–December) in several localities to examine seasonal activity, southern populations (P. nemorensis sensu Hopkins) responded only in the fall and northern populations only in the spring, but a population in Virginia responded during both seasons. Laboratory studies found that individuals from five southern populations became reproductively mature under 16:8, 12:12, and 8:16 (L:D) photoperiods but weevils in a New York population did not mature under the 8:16 photoperiod. A two-species model based on strict seasonal isolation between northern and southern populations is rejected. Morphometrics revealed significant differences in six body dimensions and three morphometric ratios among 13 populations, but there was no geographic pattern of differences to suggest the existence of two species. Sexual dimorphism in rostrum length was most pronounced in southern populations but occurred in all five populations in which it was investigated. Examination of male and female genitalia revealed similar variation in northern and southern populations and conflicted with previously reported diagnostic differences. Our study and the results of earlier work lead us to conclude that the populations previously represented by the names P. nemorensis and P. approximatus comprise one widely distributed species and display intraspecific variation in life history and morphological characters.

Eggs (24–28 h old) of Delia radicum (L.) were treated with the same doses of diflubenzuron, methoprene, juvenile hormone I, or precocene II. Diflubenzuron significantly reduced egg hatching compared with untreated and solvent-treated controls. Methoprene had a delayed effect, preventing eclosion of adults from pupae that subsequently developed from treated eggs. A commercial formulation of diflubenzuron, Dimilin®, significantly suppressed and delayed hatching of eggs treated when 3–7 h old but not of eggs treated when 24–48 h old. Diflubenzuron may be as effective as the commercial insecticide carbofuran in protecting rutabaga slices from damage, as all larvae that did hatch died shortly afterwards.

Graham (1968) demonstrated that logs became attractive to ambrosia beetles after the sapwood was subjected to anaerobic conditions. Pursuing this lead, Cade et al. (1970) and Moeck (1970a, 1970b, 1971) extracted, analyzed, and bioassayed anaerobic products from western hemlock and Douglas-fir trees and ascertained that ethanol was the principal “primary attractant” to the ambrosia beetles, Gnathotrichus sulcatus (LeConte) and Trypodendron lineatum (Olivier), respectively. The demonstration that ethanol enhanced the response of the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, to its aggregation pheromones frontalin and seudenol (Pitrnan et al. 1975) suggested that ethanol could also be involved in the primary attraction of or host recognition by bark beetles. We report that the mountain pine beetle, Dendroctonus ponderosae Hopkins, is arrested to ethanol in a laboratorv olfactometer.

Pteromalus venustus Walker is the most common parasitoid associated with the alfalfa leafcutter bee, Megachile rotundata (F.), in western Canada (Richards 1984). Leafcutter beekeepers in Canada and the United States use several methods to control P. venustus during incubation of leafcutter bee larvae, including light traps (Hobbs 1973; Richards 1984), dipping the cells in an insecticide (Brindley 1976; Parker 1979), and placing dichlorvos resin strips in the incubator (Hill et al. 1984). Previously we described the influence of temperature on survival and rate of development of the egg, larval, and pupal stages of non-diapausing P. venustus (Whitfield and Richards 1985). Here we report on the influence of temperature on rate of postdiapause development in P. venustus during leafcutter bee incubation and consider the value of this information for timing control measures for this parasitoid.

Predation on adults of the crucifer flea beetle, Phyllotreta cruciferae (Goeze), by the northern fall field cricket, Gryllus pennsylvanicus Burmeister, was recorded in laboratory tests to identify predators of flea beetles that attack canola and mustard crops. In these tests, four field-collected adult crickets all ate live adult P. icruciferae, as did 15 of 16 lateinstar cricket nymphs. The tests were carried out in 60 by 20 mm disposable plastic Petri dishes, with a stoppered hole to facilitate introduction of flea beetles. A filter paper liner in the bottom of the dish gave the insects a firm footing.

The Simulium arcticum Malloch sibling (IIS-10.11), which breeds in the Athabasca River (Procunier et al. 1984), is a major pest of cattle in central Alberta (Haufe and Croome 1980). Insecticide treatment of the river is the primary control method with the number of applications per season having increased from one to two treatments since 1978. The timing and number of applications per season are determined from information on larval instar and abundance, which is obtained from an extensive larval monitoring program that is conducted annually from late April to mid-September. Prediction of embryonic development and hatching rates of S. arcticum (IIS-10.11) eggs and when eggs enter diapause would provide for more accurate determination of the timing and number of treatments required each season.

The western flower thrips, Frankliniella occidentalis (Pergande), occurs from sea level to subalpine altitudes in western North America (Bryan and Smith 1956). Until recently, it was assumed that this species was found primarily west of the Rocky Mountains and that Frankliniella tritici (Fitch), the eastern flower thrips, was the dominant flower thrips in both eastern Canada and United States. Beshear (1983) reported F. occidentalis on cotton, peas, beans, and peanuts in Georgia. The following year, in the Niagara Peninsula of Ontario, the tomato spotted wilt virus caused extensive crop losses to greenhousegrown tomatoes and ornamentals. The virus-vector was identified as F. occidentalis (Allen and Broadbent 1986). Previously, F. fusca was the only known vector of tomato spotted wilt virus in Ontario and the eastern provinces (Paliwal 1974, 1976).