The North American species of Acrolepiopsis are reviewed and include six described species: A. assectella (Zeller), A. californica Gaedike, A. heppneri Gaedike, A. incertella (Chambers), A. leucoscia (Meyrick), and A. reticulosa (Braun). Acrolepiopsis liliivora Gaedike is considered a junior synonym of A. californica (new synonymy). Acrolepiopsis assectella, commonly known as the leek moth, is a recently invasive alien species in North America and a pest of the plant genus Allium, including leek, onion, garlic, and related cultivated plants. A key to species based on adults is provided, diagnostic characters including male and female genitalia are illustrated, and geographical distribution, host plants, and larval feeding pattern and damage (where known) are given. Diagnostics and illustrations are presented also for A. sapporensis (Matsumura); known as the Asiatic onion leafminer, it is very similar to A. assectella and is an invasive alien species present in Hawaii, though not in North America. Adult diagnostic characters of the genus Acrolepiopsis, the family Acrolepiidae, and the superfamily Yponomeutoidea are also provided and illustrated. DNA barcoding data (short sequences of the mitochondrial cytochrome c oxidase I gene) obtained for five of the six species revealed interspecific differences averaging 8.1%, whereas intraspecific variation was ≤ 0.16%, and provided unequivocal species separation matching morphology-based identifications.

Our objective was to assess the potential of carabid beetles (Coleoptera: Carabidae) as effective bioindicators of the effects of forest management at a Canadian national scale. We present a comparison of carabid beetle assemblages reported from large-scale studies across Canada. Based on the initial response following disturbance treatment, we found that carabid assemblages consistently responded to disturbance, but responses of individual species and changes in species composition were nested within the context of regional geography and finer scale differences among forest ecosystems. We also explored the relationship between rare and dominant taxa and species characteristics as they relate to dispersal capacity and use of within-stand habitat features such as coarse woody debris. We found no relationship between life-history characteristics (such as body size, wing morphology, or reported associations with downed wood) and the relative abundance or frequency of occurrence of species. Our results suggest that carabids are better suited to finer scale evaluations of the effects of forest management than to regional or national monitoring programs. We also discuss several knowledge gaps that currently limit the full potential of using carabids as bioindicators.

The stabilimentum of orb web spiders is a structure for which several functions, both mechanical and defensive, have been suggested. Argiope argentata (Fabricius) builds a stabilimentum in the form of a white diagonal cross. Analysis of over 2500 webs of this species shows that the perfect cross is seldom built and nearly two thirds of the webs contain no stabilimentum at all. Experiments with wild birds as predators show that they can use stabilimentum-like models in prey location. From these data, and a review of the defensive adaptations of orb web spiders, it is argued that the A. argentata stabilimentum is not an anti-predator device. The evidence for a mechanical function is reviewed and discussed. It is suggested that the stabilimentum provides the spider with a means of making a final adjustment to the mechanical state of the web when this is necessary.

Queenless, caged, newly emerged worker bees (Apis mellifera L.) were fed honey, 22 and 40% pollen in honey, and 22 and 40% royal jelly in honey for 14 days. Workers fed royal jelly, pollen, and honey had large, medium, and small ovaries, respectively. Royal jelly had higher nutritive value for workers’ ovarian development than did pollen, possibly because royal jelly is predigested by nurse bees and easily used by adult and larval bees. These results suggest that nurse bees could mediate workers’ ovarian development in colonies via trophallactic exchange of royal jelly. Six levels of royal jelly in honey, 0, 20, 40, 60, 80, and 100% (royal jelly without honey), were tested for their effects on workers’ ovarian development and mortality for 10 days. High levels of royal jelly increased ovarian development, but also increased worker mortality. All caged bees treated with 100% royal jelly died within 3 days. When workers were incubated at 20, 27, and 34 °C for 10 days, only bees at 34 °C developed ovaries. These findings suggest that nurse bees functioning as units which digest pollen and produce royal jelly may feed some potentially egg-laying workers in a brood chamber with royal jelly when a queen is lost in a colony. Feeding workers a diet of 50% royal jelly in honey and incubating at 34 °C for 10 days is recommended for tests of ovarian development.

Females of the polyphagous ichneumonid parasitoid, Exeristes roborator (F.), that were conditioned for 10 days to hosts in a specific habitat demonstrated associative learning by responding with ovipositor probes into the habitat alone. Females conditioned immediately after eclosion showed a higher participation rate, intensity, and duration (approximately 7 days) of learned behavior than those conditioned 5 or 10 days after eclosion, despite the fact that newly eclosed females did not probe for hosts with their ovipositors until 4 or 5 days after eclosion. The reduction in the learning ability of females within a short time after eclosion may impart a selective advantage to E. roborator by reducing the costs of learning. It could also reflect developmental constraints on the process of learning. The results suggest that carefully controlled associative learning could be exploited to improve the efficiency of host location by parasitoids released in biological-control programs.

Window flight traps baited with ethanol attracted 15 genera representing 25 species of scolytids. Monarthrum fasciatum and Xyleborus saxeseni were the most frequently trapped scolytids. Evidence for seasonal flight periods and vertical flight distribution are presented for Hypothenemus dissimilis, X. ferrugineus, X. saxeseni, X. sayi, X. xylographus, M. fasciatum, M. mali, and Corthylus columbianus. Live Q. velutina injected with ethanol attracted five species of scolytids: X. saxeseni, X. xylographus, M. fasciatum, M. mali, and C. columbianus.

Data on the parasitic associations of larval water mites with imaginal aquatic insects are reviewed. Documented associations now are known for larvae of 47 genera of water mites in 23 families representing all seven superfamilies. The particular importance of the nematocerous Diptera, and especially the Chironomidae, as hosts of larval water mites is demonstrated, primarily on the basis of new data. New insights into the evolution of parasitic behaviour patterns in larval water mites are discussed.

Supercooling point, biochemical metabolites, and water content of the larvae of Choristoneura fumiferana (Clem.) were measured during pre-diapause and diapause development under laboratory conditions. Supercooling point dropped significantly, from a mean value of −22.9 °C to −31.7 °C during the 3-week pre-diapause development. Supercooling point continued to decline down to −34.5 °C after the beginning of diapause. Water content also dropped significantly during pre-diapause development and was maintained at a low level during diapause. Significant amounts of glycerol were detected only when the larvae were 5 weeks into diapause and the glycerol level continued to increase until week 20 when it was almost 10 times its original level. Glycogen was nearly depleted after diapause, but lipid remained at a relatively high level. Little change in glucose and trehalose content was found during diapause in spite of their initial rise before diapause. Larvae could survive low temperatures close to their supercooling point without freezing but none survived freezing, suggesting that this species is freeze-intolerant. First-instar larvae were found to excrete green material out of their body within 5 days after emergence. Removal of this material from the insect body coincided with a significant drop in supercooling point, indicating that a potential nucleating factor might be involved in the green material. The implications of these results for the overwintering strategy of C. fumiferana are discussed.

Honeydew utilization by the ant Lasius niger L. (Hymenoptera: Formicidae), honeydew excretion cost for the aphid Aphis craccivora Koch, and ant protection service for aphids against the lady beetle Coccinella septempunctata L. (Coleoptera: Coccinellidae) were examined in a laboratory. The duration of honeydew utilization by ants increased with increase in aphid density. The presence of ants shortened the residence time of the lady beetle larva on a plant and reduced the proportion of aphids eaten. At a density of 5 aphids per plant, one aphid with ants excreted honeydew at a frequency two times higher than that of an aphid without ants, but not at a density of 100 aphids per plant. Therefore, a larger aphid colony may increase the benefit and decrease the cost of ant attendance.

Generally throughout eastern Canada, wood borers of the genus Monochamus present the greatest single theat to softwood logs that must remain in the woods thrnughoat the summer and to standing trees killed as a result of fire or other disturbance. Althoush a considerable body of literature has been accumulated on the general biology and taxonomy of rlie econonucally important species (4, 5, 11, 15), on the ainount of damage caused by them under particular circumstances (2, 12), and on the protection of logs from damage (1, 3, 10, 13, 14), comparatively little detail is available on their seasonal development.

Studies on the ecology of the fauna of apple orchards in Nova Scotia were initiated in 1943, to determine the long-term influence of spray chemicals on the populations of apple-infesting insects. At that time it was felt that the indiscriminate use of spray chemicals in the control of orchard pests was sometimes creating worse problems than those corrected–and was threatening the economy of apple production; and that there was an urgent need to determine, if possible, how to harmonize biological and chemical control. A more comprehensive discussion on the biological and philosophical concepts on which the studies were based may be found elsewhere (Pickett et al., 1946; Pickett, 1949a; 1949b).

The European earwig is an excellent experimental animal for many laboratory and field studies of insect ecology and behavior, but special rearing, marking, and trapping techniques are required to exploit the insects’ potential fully. This paper describes an artificial nest and associated techniques which reduce rearing mortality below 10%. Methods of studying events in natural nests, and of capturing and marking individuals for population studies, also are described.

This study assesses the effects of the veterinary medical product ivermectin (IVM) in a range of concentrations on adult reproductive physiology and larval mortality of the dung beetle Euoniticellus intermedius (Reiche) (Coleoptera: Scarabaeidae). The ecotoxicological tests comprised eight treatments, including two controls and six increasing ivermectina concentrations (3.16, 10.0, 31.6, 63.2, 100, and 316 µg IVM/kg fresh dung). After 10 days of exposure, the females were dissected and the brood balls counted (fecundity). The brood balls were opened 15 days later and live larvae were counted to estimate larval mortality. Ivermectin altered the morphology of the ovary and stopped vitellogenesis, causing oocyte resorption and thus decreasing fecundity. The 30% threshold of decline in fecundity was reached at 115.9 µg IVM/kg dung, with no observed effect concentration (NOEC) and lowest observed effect concentration (LOEC) values of 10.0 and 31.6 µg IVM/kg dung, respectively. Larval sensitivity to ivermectin was higher, with a lethal concentration required to kill 50% of the population of 85.9 μg IVM/kg dung, and NOEC and LOEC of 3.16 and 10.0 µg IVM/kg dung, respectively. After cattle were treated with ivermectin at the recommended dose, the ivermectin concentration in their dung during the two first weeks after administration far exceeded the thresholds determined for E. intermedius.

Unmated female A. kühniella (Zell.) emitted a sex pheromone at the beginning of the light period of a 24 hour cycle of light and dark periods. There were no differences apparent in the duration of the calling posture by females in light of 1, 40, or 200 lux. A sex pheromone was extracted from the abdominal tips of unmated females of various ages with organic solvents, 3-day-old females gave the most potent extracts. Extracts of equal potence were obtained from females at different times during the diel cycles of photoperiod. The response of males to the extract was maximal at dawn, increased with age for 5 days, and was greater in light of 1 lux intensity than of 200 lux. Both sexes showed an anticipation of the beginning of the light period in their sexual behaviour, but if the timing of the cycle of photoperiod was changed the behaviour of both sexes became synchronised to the new cycle on its second or third occurrence.

To determine the dispersal of coccinellids in corn fields, two methods were used: sticky traps were placed at different elevations to catch the beetles in flight, and a sucrose solution was sprayed on the upper or lower portions of plants to concentrate beetles.

The results show that the distribution on the plants is closely related to the manner of dispersal of the species, the Hippodamia species fly at a greater height than C. maculata, and H. convergens and H. 13-punctata are, respectively, about 15 and 9 times as mobile as C. maculata. The results generally support the idea that entomophagous coccinellids are more nomadic than their phytophagous relatives.

The nine species; of Timema Scudder known previously from California, Arizona, and Nevada are redescribed and three new species are added: Timema nakipa from Baja California, Mexico: T. tahoe from Nevada; and T. cristinae from Santa Barbara County, California. Timema nakipa and T. podura Strohecker are the only representatives of Timema known from Mexico. Keys and identification tables are presented for identification of species.

Development and survival of the predatory pentatomids Podisus maculiventris (Say) and Podisus sagitta (Fab.) were studied at six constant temperatures ranging from 19 to 35 °C. Time required for development from egg to adult ranged from 48.9 days (19 °C) to 18.9 days (30 °C) for P. maculiventris and from 51.9 days (19 °C) to 16.9 days (33 °C) for P. sagitta. At 33 °C, eggs of P. maculiventris did not hatch and development of nymphs that had emerged at 23 °C was retarded; none of the first-instar nymphs incubated at 35 °C survived the next moult. A constant temperature of 35 °C was fatal to P. sagitta eggs and extended the developmental period of nymphs from 23 °C. Egg hatch ranged from 47% (19 °C) to 57% (27 °C) for P. maculiventris and from 54% (33 °C) to 71% (27 °C) for P. sagitta. Nymphal survival was high at moderate temperatures, with 63–78% and 65–82% of the first-instar nymphs of the respective species reaching adulthood. Mortality during the nymphal stage was significantly increased at high temperatures, but was considerably lower for P. sagitta than for P. maculiventris. Lower threshold temperatures for egg and nymphal development were estimated to be 10.7 and 11.7 °C for P. maculiventris, and 13.3 and 12.2 °C for P. sagitta. Thermal requirements for these stages were 78.2 and 275.5 degree-days, and 60.9 and 265.5 degree-days, respectively. These observations suggest that P. sagitta is somewhat better adapted to high temperatures than is P. maculiventris.

The alarm pheromone of the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is present in the droplet of anal fluid produced by second-instar nymphs when attacked by predators. Because the anal droplet is used in defense against arthropod predators, it was hypothesized that the alarm pheromone (decyl acetate plus dodecyl acetate) acts as a defensive allomone. This hypothesis was refuted by the demonstration that two predators use the pheromone as a prey-finding kairomone. On a leaf arena, Orius tristicolor White (Hemiptera: Anthocoridae) increased its rate of turning in response to the pheromone, and spent 25% of its time within 5 mm of a pheromone source. When given a choice between connected leaf discs containing a pheromone- or solvent-treated wick, Amblyseius cucumeris (Oudemans) (Acarina: Phytoseiidae) spent a greater proportion of time on the pheromone-containing disc, suggesting an arrestment effect.

The flight habits of any scolytid beetle are an important aspect of its biology, and times of flight should be known for effective chemical protection of logs against its attacks. Consequently, during the course of biological and chemical control investigations of the ambrosia beetle, Trypodendron lineatum (Oliv.), from 1954 through 1956, much attention was directed to a study of its flight activity. This species is well known to attack early in the spring. There are other attack flights later in the season but far fewer beetles are involved then. The beetles also fly at the time they leave the brood logs to enter forest litter, where they overwinter. Several methods were used to study the influence of weather, season, and other factors on flights of Trypodendron and, to a lesser extent, of other scolytids. These methods and some of the data secured are described and discussed in this paper.

Carabid taxa inhabiting the montane forests of México and Central America are analyzed using cladistic biogeographic methods. Taxa exhibiting the Nearctic, Meso-American Montane, and Paleo-American distributional patterns are included in the analysis. Widespread taxa are assumed to indicate that the areas of endemism they inhabit are closely related, and the general pattern of area relationships is determined using parsimony analysis. Of the nine areas of endemism recognized in the analysis, the Sierra Madre Oriental is considered the most distinct. The northern Sierra Madre Occidental, Arizona Mountains, and Sonoran Desert comprise one monophyletic set of areas, as do the more southerly areas of the Sierra Transvolcanica, Sierra Madre del Sur, Chiapan–Guatemalan highlands, and Talamancan Cordillera. The southern Sierra Madre Occidental area of endemism is equivocally related to both areas to the north and areas to the south. Biogeographic information derived from widespread species is as congruent with the general area cladogram as information derived from groups with precinctive species, indicating that the same biogeographic barriers often limit distributions of both widespread species and more inclusive clades comprising precinctive species. Taxa exhibiting the Meso-American Montane Pattern are more congruent with the general area cladogram than those representing the Nearctic Pattern, even though they exhibit less fidelity to highland habitats.