The female of Tarsonemus indoapis n. sp. is described, illustrated, and its unusual morphological features are discussed. This mite is apparently restricted to the head region, where its microhabitat is possibly the posterior tentorial pits, of the adult host, Apis indica Fabricius. It is compared briefly with other tarsonemid symbionts of bees, that is, species of Acarapis and Tarsonemus apis Rennie.

White fir cones were sampled for insect damage from wild stands in California and Nevada during 1984–1986. Insects were recovered from cones and seed damage was partitioned by insect species. The important phytophagous insects were separated into guilds: the cone- and seed-mining guild, Dioryctria abietivorella Groté, Eucosma prob. siskiyouana (Kearfoot), Cydia prob. bracteatana (Fernald), Barbara sp.; the seed-feeding guild, Megastigmus pinus Parfitt, M. rafni Hoffmeyer, Earomyia abietum McAlpine; and the scale- and bract-feeding guild, Asynapta hopkinsi Felt, Dasineura prob. abiesemia Foote, Resseliella conicola (Foote), Strobilomyia abietis (Huckett). Total damage by insects varied by year and site, reaching a maximum of 47% in 1986 on one site and a minimum of 12.5% in 1984 on another. Abortion and incomplete development also were major factors in the production of sound seed. Populations of white fir cone and seed insects varied with cone crop but also were affected by the occurrence of cone crops on alternate hosts. During most years, the seed-mining guild insects were the major cause of seed damage.

Adult emergence of the spotted tentiform leafminer, Phyllonorycter blancardella (F.), and its primary endoparasite, Apanteles ornigis Weed, from overwintering pupae was studied at five constant temperatures. Days to 50% emergence for P. blancardella were 55.4, 24.4, 14.4, 10.8, and 8.3 and for A. ornigis were ∞, 47.8, 25.6, 17.6, and 15.1 at 8°, 12°, 16°, 20°, and 24 °C, respectively. The rate of pupal development was approximately a linear function of temperature for P. blancardella but was nonlinear for A. ornigis. The threshold of development, estimated from the 50% emergence data, was 4.4 ±.33 °C for the host and 9.6 ±.50 °C for the parasite. The development time for the host was approximately one half that for the parasite at temperatures 12°–24 °C. The difference in emergence dates between host and parasite under normal Nova Scotia conditions was predicted to be 35 days. The timing of chemical controls in an integrated pest management program could be predicted from the accumulation of daily development units based on the power function for both species, provided a field study is undertaken to confirm the extrapolation to diurnal temperature regimes.

A blacklight trap was established at 3790 m in 1978 and at 3505 m, 3657 m, 3790 m, and 3810 m, in 1979, on the alpine tundra in Colorado. Weekly catches from 6 July to 4 August 1978, and 26 June to 14 September 1979, resulted in ca. 3500 individuals of over 48 species of moths. These results establish that a greater diversity of moths exists and greater nocturnal flight activity occurs than was previously supposed for alpine tundra communities. The implications for pollination and insect foraging are discussed.

Micro-organisms that seem to be symbiotic are known to occur in many insects (Steinhaus, 1949). Often these micro-organisms are retained for at least a part of their iife in special organs in the insect's body called ‘mycetomes’. Mansour (1935) following a study of a number of beetles cnntaining micro-organisms concluded, in the two closely related species Sitophilus granarius (L) and Sitophilus oryza (L) that while both species have mycetonies only S. oryza had micro-organisms; a conclusion that his received some general acceptance (Steinhaus, 1946; Wigglesworth, 1947). Thus it could be questioned if the micro-organisms in S. oryza were of benefit to it since S. granarius survived apparently without any (Mansour). However, it has been shown that in some beetles (Blewett & Fraenkel, 1944), in the body louse (Aschner, 1935), and in the hug, Rhodnius, (Brecher & Wigglesworth, 1944) the associated micro-organisms are of considerable importance to the insect. It therefore seemed worth while to study further the condition existing in S. oryza and S. granarius; and in the early stages of this work some interesting phenomena have been observed.

Utilizing the knowledge of their direct effects, the materials ryania, carbaryl, and Animert V-101 applied to a uniformly distributed population of the European red mite, Panonychus ulmi (Koch), altered the populations in plots in an apple orchard. Trends after treatment in both host mite and predator populations were assessed. Supplementary applications of the acaricides Animert V-101 or dicofol directed against certain generations of P. ulmi controlled outbreaks and altered the faunal levels during the following season. Ryania was largely innocuous to most species of predators with the exception of Atractotomus mali (Meyer) and Diaphnocoris spp., carbaryl was detrimental to most predacious species, and Animert V-101, while selectively toxic to phytophagous mites, was innocuous to all predacious insects and Typhlodromus pyri Scheuten.Phytophagous mite populations may be altered to almost prescribed levels with pesticides when the predator populations are known. This allows selective chemicals to be used to complement the predator effect and maintain red mites below the threshold of damage.

Adults of Dendroctonus ponderosae Hopkins were stored at 1 °C in 2-mil polyethylene bags containing moistened excelsior. Under these conditions, 85% of the beetles survived after 30 days. Stored adults showed no decrease in fecundity but the percentage of females in their broods increased with storage duration. Handling prior to storage and interruptions in the storage period resulted in a decrease in survival. Female adults survived storage better than males.

Many factors have been examined that affect simuliid larval distribution in a stream but little has been published on interspecific competition influencing their distribution. Certain black fly species distribute themselves over a suitable substrate in a regular manner with an open space around each larva. The individuals of these species will strike at others entering within this space resulting in the departure of one or other of the combatants. This establishes a regular pattern of spaced larvae of a certain density, which may be influenced by current velocity, over areas of suitable substrate (Colbo 1979). However, larvae of other species clump without apparent spacing and less readily move when contacted.

Morphological, life history, and distributional data are presented for North American species of the subgenus Allomomonia Cook, 1968. Adults of Stygomomonia (Allomomonia) moodyi Mitchell are redescribed, and deutonymphs and adults of four new species, S. (A.) pacifica, S. (A.) mendocinoensis, S. (A.) mitchelli, and S. (A.) atnarkicola, are described for the first time. Larvae tentatively identified as S. (A.) mitchelli are also described, and host associations of these, and larvae that appear to belong to other species of Stygomomonia, are presented and discussed. New distributional data are presented for all species. A new diagnosis of Allomomonia is proposed, two new species groups, the moodyi and mitchelli groups, are proposed and diagnosed, and a key to adults of North American species of the subgenus is included.

Megachile rotundata (F.) is a domesticated bee used to pollinate alfalfa in southern Alberta. There it may have four species of parasites, all chalcidoids. These parasites are removable by water traps before the hives are set in the field. Three of these parasites, Monodontomerus obscurus Westw., Dibrachys maculipennis Sz., and Pteromalus venustus Wlkr,, are European in origin. The first seems not to be established in Canada; the latter two have been reared from Canadian species of Megachile and thereby may prove a source of parasitism. The fourth species, Melittobia chalybii Ashm., is a widespread, nearctic, multivoltine species and is known as a laboratory pest of hymenopterous nests; it is likely to be the major parasite in rotundata nests. A key is given for the parasitic species.

The leaf galler Diplolepis polita (Ashmead), known only from Rosa acicularis Lindl. west of the Rocky Mountains, is recorded for the first time on the introduced, urban shrub rose Rosa rugosa Thunb. Inquilines and parasitoids commonly kill over 90% of the inducers in populations of galls found in natural habitats, whereas 55% of the galls from the urban roses contained an inducer. Differences in component communities associated with galls on domestic and wild roses are likely indicative of a recently established population in an atypical habitat. Occurrence of D. polita on this new host also provides insight into the host specificity and vagility of cynipid wasps.

The blueberry maggot, Rhagoletis mendax Curran, is the most important insect pest of lowbush blueberries. Concern for maggot does not generally result from direct crop losses, but from its presence in harvested fruit which can affect marketability.

Fortunately, the blueberry maggot is not a problem in all lowbush blueberry areas (Wood 1979), but where it does occur, producers are advised to apply one or two sprays annually. General recommendations often result in the unnecessary use of insecticides, especially in years when populations are at low levels because of natural control and management practices. Such misuse could be prevented if monitoring techniques were developed that provide information on seasonal adult prevalence.

Adult parasitoid females can obtain proteins and lipid by consuming the haemolymph of their host. In Trichogramma Westwood (Hymenoptera: Trichogrammatidae) species, host feeding on the host egg occurs after oviposition and leads to smaller offspring. We tested the effect of age and hunger on host-feeding behaviour of female Trichogramma euproctidis Girault. Young and old females, either starved, water fed, or honey fed, were observed and the host-feeding frequency, duration, distribution, and number of hosts used for nutrition were measured. The sex ratio (proportion of males) allocated to parasitised hosts where host feeding occurred and time taken to parasitise 10 hosts (indicator of female mobility) were also noted. The majority of females host fed on the first host encountered. Age had no impact on frequency, duration, number of hosts used, and mobility of T. euproctidis. Starved females host fed longer and were less mobile. The sex ratio of the progeny emerging from the first host parasitised was more male biased when host feeding occurred. Host feeding had no effect on the sex ratio deposited elsewhere in the sequence of hosts encountered. Age of female had no effect on host feeding, possibly because host feeding incurs little cost for this species. To host feed on the first host parasitised, in which a male is allocated, is less costly in terms of fitness and represents a strategic choice for the female.

Dry-weight changes in the midgut, abdominal fat body, flight muscles, pterothoracic cuticle, and reproductive tract were measured in unfed male Rhodnius prolixus Stål following eclosion and in males fed a single blood meal on day 5 post-ecdysis. Males, which had fed to repletion as fifth instar nymphs, emerged from the nymphal–adult moult with approximately the same quantity of blood solids in the midgut as observed in fully engorged males. Carry-over of the blood-meal from the fifth instar was sufficient to allow the fat body, flight muscles, and pterothoracic cuticle in unfed males to attain over 85% of the weight accretion observed in fed males. The reproductive tract dry weight in unfed adults increased only 60–65% of that in fed adults. Flight-muscle and reproductive-tract development in fed insects reached growth plateaux in 2 and 3 weeks after the final nymphal moult, while cuticle development continued for up to 10 days. It is concluded that R. prolixus males which emerge from fully engorged fifth instars do not require a blood meal in the adult stage to trigger growth processes and tissue development, but if the adult takes at least one blood meal, significant increases in the reproductive-tract dry weight and slight increases in the dry weights of other tissues will occur.

The world genera (15 in all) of Drosophilidae with bare (i.e., non-plumose) aristae are brought together, and a key is provided for identifying them. Notes are provided in the key on type species, synonymy, numbers and distributions of included species, and pertinent literature. The genus Paracacoxenus Hardy is revised to include not only its one Nearctic species, guttatus Hardy and Wheeler, but also three European species that were originally assigned to Cacoxenus Loew, i.e., argyreator (Frey), exiguus (Duda), and inquilinus (Hendel). Lectotypes are designated for Cacoxenus punctatus Duda (a junior synonym of Gitonides perspicax Knab), for Gitona vlasovi Duda, for Paracacoxenus argyreator (Frey), and for P. exiguus (Duda). The paper includes 30 figures.

Some time ago in examining our species of ant lions I noticed that our two large genera, Myrmeleon and Brachynemurus, could readily be separated by the position of the origin of the radial sector; in one much nearer to the base of the wing than in the other. The characters previously used for Brachynemurns, as the forked costal veinlets, the length of the tibial spurs, etc., had not been satisfactory; and the discovery of this distinction led me to examine the other forms of the family with a view to their better classification.

Storage of diapausing larvae of Choristoneura viridis and C. occidentalis at low temperature (2°C) appeared to be sufficient stimulus to terminate diapause. Reactivation at 25°C occurred sooner and was more synchronous with longer storage at 2°C. Highest survival was obtained after storage of 20 to 22 weeks for both C. viridis and C. occidentalis. Intraspecific and interspecific reactivation rates were compared by analysis of covariance, using the model ln Y = a + B ln X , where Y = larval emergence in days at 25°C and X = storage in weeks at 2°C. Intraspecific sex differences were not significant, indicating that protandry observed in this laboratory in both species must be due to some other factor. C. viridis had substantially less stringent thermal requirements for diapause termination than C. occidentalis. Diapause in the two species is discussed.

The six-spotted leafhopper, Macrosteles fascifrons (Stål), is the only known host of Pachygonatopus minimus Fenton; parasitism has reached 37%. The female adult is also a predator of the leafhopper. In the adult stage of the parasite the sexes differ in form, color and habits; the male is winged and the female wingless. The egg is laid in the abdomen of the host. As the larva develops it protrudes through an intersegmental membrane. There are five larval instars. The first four are sedentary and attached to the host; the fifth is an active feeding stage. The larva spins a cocoon within which it pupates. The period from egg to adult is about 28 days. P. minimus does not provide effective control of the leafhopper.

Prosimulium fuscum and P. mixtum larvae and adults may be readily separated on the basis of unique complements of electromorphs at the 6-phosphogluconate dehydrogenase locus. The species are closely related and share common electromorphs at 10 other polymorphic and monomorphic loci. Numerical analysis of 24 morphological characters from larvae shows cephalic fan ray number and the length of the postgenal bridge plus hypostomium can be used to identify most individuals to species. A possible environmental component in determination of morphotype may prevent correct identification of all larvae. Lack of utility of other characters currently used in keys to separate the species is discussed.