The synonymy, distribution, host range, and life history of the gregarious larval–pupal parasitoid Tachinaephagus zealandicus Ashmead, is discussed. Laboratory studies of its biology were conducted at 25° ± 2 °C using Musca domestica L. as host. Its developmental stages are described. Under laboratory conditions its life cycle lasted 23–27 days. Parasitoid development accelerated with higher average densities per host. Single standardized hosts produced 3–18 adult parasitoids. Mated females provided with hosts lived 50.4–67.2 h. The average length of the reproductive period and number of hosts parasitized were independent of host density; however, the average number of eggs deposited per host increased at lower host densities. Adult emergence displayed circadian rhythmicity independent of photoperiod over 3+ days.

The earliness or lateness of the hatching period in Melanoplus sanguinipes (Fabr.) affects the type and amount of damage to the crop and the timing of control measures. An empirical model for prediction of hatching at each decile of egg populations was developed by multiple regression using daily maximum air temperatures for a unit interval of 5 days from 2 March to 29 June and embryonic development in the preceding fall. The model accounted for a maximum of 96% of the variance in hatching date. It showed the average effect of a unit change of 1° of daily maximum temperature for each of the 24 5-day intervals on the number of days to hatch. The time and pattern of hatching of the major bulk of egg population was dependent mainly on spring temperature; however, fall embryonic development accounted for considerable variation in hatching time especially of the less developed eggs. The implications for population growth and certain assumptions made during the analyses in this study are discussed.

During 1972, spruce budworm infested white spruce and balsam fir trees were sprayed aerially with a low dose of fenitrothion (0.25 oz AI/ac), entomopox virus (EPV) at 7.6 × 1010 polyhedra/ac, nuclear polyhedrosis virus (NPV) at 2.7 × 1011 polyhedra/ac, or each virus–fenitrothion combination. Fenitrothion (active ingredient), NPV, and EPV deposited at ground level at 5%, 31%, and 42%, respectively, of the amounts emitted.

In the year of application, NPV + fenitrothion was highly effective in population reduction and foliage protection especially on; balsam fir although a higher virus infection rate was found on white spruce than on balsam fir. EPV + fenitrothion also provided a high level of foliage protection and apparently reduced surviving female:male sex ratio to 1:2 compared with the normal 1:1 ratio. NPV + insecticide caused highest larval mortality, highest incidence of virus, lowest rate of moth emergence, fewest progeny, and lowest rate of progeny survival. The natural incidence of microsporidia was low in all plots.

In the year following application, the NPV + insecticide treated plot again showed lowest population density, highest larval mortality and incidence of virus, and low defoliation and egg mass density. However, there was a higher proportion of viable eggs deposited than in the previous year. Egg parasitism by Trichogramma minutum increased by 1.5 to 4.2% in plots treated with virus only and declined by 1.6 to 10.5% in insecticide treated plots and by 1.2% in untreated check plot. The transmission of the virus from one year to the next is considered to be of paramount importance in the future use of this pathogen in spruce budworm control.

The functional response of Spalangia endius Walker was described by a linear relationship between attack rate and density of house fly pupae. S. endius searched well at higher host densities and in 72 h, appeared capable of attacking more than 80 pupae per female under laboratory conditions. The response of Muscidifurax raptor G. & S. was quadratic as poor searching ability limited this parasitoid’s attack rate at high host densities. Individual parasitoid efficiency of both species was reduced by intraspecific competition when parasitoid density was increased.

Topical application of three analogues of juvenile hormone, ZR-515 (isopropyl 11-methoxy-3,7,11-trimethyldodeca-2,4-dienoate), ZR-777 (prop-2-ynyl 3,7,11-trimethyldodeca-2,4-dienoate), and JH-25 (7-ethoxy-1 (p-ethylphenoxy)-3,7-dimethyl-2-octene) to pre-diapause adults of the white pine weevil, Pissodes strobi (Peck), induced ovarian development and resorption of fat bodies. Control of this species by hormonal induction of reproductive maturity and related metabolic alterations at the onset of winter is suggested.

Females of Anthrenus flavipes LeConte emit a sex pheromone and exhibit a calling behavior that is related to the release of the pheromone. Calling began after the onset of light, was most intense 1 to 2 h later, and ceased after 4 h of light when the insects were held in a 16:8 LD photoperiod. Chemical studies showed the presence of a major sex pheromone that is an unsaturated carboxylic acid.

Eight new species of Amblysellus are described and illustrated: A. cereus n. sp. from Guatemala, A. torqus n. sp. and A. excavus n. sp. from Ecuador, A. dedecus n. sp., A. necopinus n. sp., A. copulus n. sp., and A. macularis n. sp. from Mexico, and A. acuerus n. sp. from North America north of Mexico. A key to the known species of the genus is presented.

The Holarctic genus Symphoromyia, the biting snipe flies, is discussed and a taxonomic history of the group is reviewed. Five subgenera including Symphoromyia s. str., Paraphoromyia Becker, and three new subgenera, Axinicera, Pogonaria and Ochleromyia, are established and a key for their separation and recognition of included species-groups is presented. Each subgenus and its associated species-groups are discussed and compared with respect to distribution, morphology, and evolutionary trends. Known aspects of biology for the genus are presented to include: (1) a generalized life cycle; (2) immatures; (3) natural enemies; (4) female biting activity; (5) male swarm behavior.

Nine species of hymenopterous parasitoids were trapped on sticky traps as they were attracted to red cedar logs infested with the eastern jumper bark beetle, Phloeosinus dentatus (Say). All were successfully reared from infested logs. The parasitoids Cheiropachus arizoninsis (Ashmead), Eurytoma aequabilis Bugbee, Heydenia unica Cook & Davis, and Spathius impus Matthews were reared directly from P. dentatus larvae.

Five species of parasitoids reared from P. dentatus larvae or from infested logs commonly attack the southern pine beetle and Ips spp. beetles, indicating that P. dentatus may be an important alternate host when the other host populations are low.

Thermoregulation in nests of two colonies of Vespula arenaria and two colonies of V. maculata was studied in relationship to seasonal changes in colony biomass. The colonies achieved maximum ability to resist ambient temperatures of 5 °C and maintained high nest temperatures on or within a week of achieving maximum biomass. During this period the colonies were capable of producing about.20 to.35 cal per gram of biomass per minute. The caloric production per gram required to maintain the normal nest temperatures of 30 °C and 32 °C in an ambient temperature of 25 °C was much less, but was greater for the V. maculata colonies than for the V. arenaria colonies. The greater efficiency in thermoregulation by V. arenaria is largely due to the fact that nests of this species have a greater biomass of wasps than approximately equal sized nests of V. maculata.

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.

The Holarctic species of the genus Pygocryptus Roman (Hymenoptera: Ichneumonidae) are revised. Two previously recognized species, P. grandis from Europe and P. echthroides from North America, are retained; four new species and three subspecies for P. echthroides are proposed. A diagnostic key and descriptions of the new species and subspecies are presented.