The nesting behaviour of the euglossine bee Euplusia surinamensis was observed on the Osa Peninsula of Costa Rica. We found that female bees nest in aggregations, re-use old nests, will take over abandoned nests shortly after the original owner is removed, and will fight off invading bees which attempt to take over their nests. We suggest that the nesting aggregations give bees the opportunity to use old nests and take over partially provisioned nests if the original owner disappears. In this way bees are able to increase their rate of egg laying above that which would be possible with solitary nesting and de novo nest construction.

Euxoa ustulata n. sp., allied to Euxoa perexcellens (Grote), is described from northern California. Adults and genitalia of both species are illustrated.

In 1972, limb jarring, tanglefoot trunk barrier, emergence trap, and insecticide spray knockdown methods of sampling for adult pecan weevil, Curculio caryae (Horn), were compared. The latter two methods were most efficient in detecting onset of adult emergence, seasonal fluctuations in emergence, and population differences among sample dates and among trees. In 1973, further comparisons of the latter two methods gave results similar to 1972 results. The required sample size was influenced by population density. The number of pecan trees to be sampled for a 20% standard deviation of the mean was small enough to be practical for grower use for most sample dates in 1973 and at dates near peak emergence in 1972.

Data obtained by sampling studies during 1972 and 1973 were used to develop equations for predicting the number of adult pecan weevils, Curculio caryae (Horn), in a tree from the number of pecan weevils trapped beneath that tree on a given date. Two of the models then were tested to determine their effectiveness in estimating weevil populations.

When the population estimates obtained from the model built from the early season data in 1972 (model A) were compared with the actual populations found in the trees in 1973, it was found that 71.7% of the observed values in 1973 fell within the 95% confidence intervals for the predicted values. When similar comparisons were made utilizing the model built from early season data in 1973 (model C), 95% of the observed population values in 1972 fell within the confidence intervals for the predicted values. Three-dimensional response surfaces generated from the models were similar and revealed that as the season progressed, the number of pecan weevils predicted from any trap value increased at an increasing rate.

The systematic status of the genus Tarsocheylus Berlese, 1904 and the position of the family Tarsocheylidae Atyeo and Baker, 1964 in the Prostigmata is reviewed. The family does not belong in either the Raphignathoidea or the Anystoidea but in its own superfamily, the Tarsocheyloidea, which is described for this purpose. In turn, this superfamily is placed alongside the Heterocheyloidea in the Heterostigmata.

Because the type-species of Tarsocheylus, T. paradoxus Berlese, 1904, is conspecific with Hoplocheylus discalis Atyeo and Baker, 1964 (new synonymy), the concept of Hoplocheylus Atyeo and Baker, 1964, which has remained until now as originally proposed, is the same as that of Tarsocheylus. However, a new case is made for recognizing these genera as mutually distinct, based on other morphological criteria. Tarsocheylus atomarius Berlese, 1913, the type-species of Hoplocheylus, is apparently conspecific with Hoplocheylus canadensis Marshall, 1966 (new synonymy) and perhaps with one or two other described species from North America. A third generic entity, represented by Hoplocheylus johnstoni Atyeo and Baker, 1964, is noted but not named or formally described. Hoplocheylus pickardi Smiley and Moser, 1968 is conspecific with H. similis Delfinado and Baker, 1974 (new synonymy).

Hemitarsocheylus Soliman and Zaher, 1975, which was described as a new genus in the Tarsocheylidae, is congeneric with Stigmocheylus Berlese, 1910 (new synonymy). This genus does not belong in the Tarsocheyloidea, but rather in the Anystoidea.

A list of character states found useful in recognizing groupings of species of Tarsocheylidae is presented. Based on the collection data with specimens representing described and undescribed species at hand, the known distribution of the Tarsocheylidae is extended to include Australia and western North America, and the second known instance of an association with passalid beetles is recorded.

From a phylogenetic standpoint, the Tarsocheyloidea and Heterocheyloidea are proposed as sister groups that together constitute a new suprafamilial taxon, the Tarsocheylina. In turn, the Tarsocheylina and Tarsonemina are proposed as sister groups, and both are described; together, they form the Heterostigmata.

The systematic and phylogenetic relationships of the Heterostigmata (including the Tarsonemina) to the Prostigmata and the Astigmata are reviewed. Not only should the Heterostigmata be retained in the Prostigmata but it should be lowered in hierarchic rank, such that it is a part of the Eleutherengona. The stock that gave rise to the Anystoidea and related superfamilies is shown to be ancestral to the Heterostigmata as well.

The activity of two insect growth disruptors PH 6038 and PH 6040 was assessed against larvae of the winter moth, Operophtera brumata (L.) in the laboratory and field. Larvae fed on foliage treated with PH 6038 and PH 6040 until death occurred at ecdysis owing to disruption in cuticle formation. Field tests with PH 6040 indicated that concentrations of 165 ppm were effective for control. As measured by bioassay, using winter moth larvae, PH 6040 was persistent for at least 28 days in the field.

A small colony of the striped flea beetle, Phyllotreta striolala (F.), has been maintained in a cage in the greenhouse for more than 21/2 years. Horseradish [Armoracia rusticana (Lam) Gaertn., Mey. & Scherb.] was found to be a suitable host plant, and the caged beetle colony has followed a similar life cycle to natural populations in the field.

A key is given to species of Aphis L. on Umbelliferae in Manitoba: A. spiraecola Patch, A. heraclella Davis, A. decepta Hottes and Frison, A. thaspii Oestlund, and A. saniculae Williams. A. signatis Hottes and Frison is considered to be a synonym of A. thaspii, and A. luridis Hottes and Frison a synonym of A. saniculae.

A new species of sarcophagid, Colcondamyia auditrix, is described, which locates its cicada host by sound. The fly was shown to respond to the mating song of the male cicada, and the majority of parasitized cicadas were male. Parasitism of females occasionally occurs when they are attracted to males simultaneously with the parasite. Levels of parasitism varied from 18.6% in 1962 to 0.2% in 1967 to 14.1% in 1973. Male cicadas lost their sound producing capability following parasitization, rendering them inaccessible to further female flies and thus apparently preventing multiple parasitism.

Body weight, head width, and cercus length and width of adult male earwigs were found to be polymorphic in both field-collected and laboratory-reared samples. The view that the polymorphisms are the result of environmentally induced ’heterogonic growth’ is discounted. Seasonal, annual, and geographic variation in morph frequencies are demonstrated and discussed.

In 1965, strains of the predaceous phytoseiid mite, Typhlodromus occidentalis Nesbitt, had developed resistance to azinphosmethyl, one of the organophosphate insecticides used to control the codling moth, Laspeyresia pomonella (L.). From 1966 to 1968, trials with integrated mite control in growers’ orchards were carried out successfully preserving the predator T. occidentalis. In most cases, an application of oil at the half-inch green bud stage was applied. The integrated concept of orchard mite control was recommended to the British Columbia fruit industry in 1969 and gained wide acceptance. In 1974, a survey of eight of the original integrated control orchards revealed that none of them had been treated with a summer acaricide since 1968. In six orchards, application of oil at the half-inch green bud stage had been used annually but two had not even received the oil spray. In all the orchards there was a good biological balance of a few predators and a few prey.

A pour-on formulation of ronnel and 1% coumaphos dust were tested for control of cattle lice under southern Ontario feedlot conditions. Moderate to heavy populations of the cattle biting louse Bovicola bovis and light populations of the sucking lice Linognathus vituli and Haematopinus eurysternus were present on the treated cattle. The ronnel and coumaphos dust gave excellent reduction of lice populations for 43 and 35 days, respectively.

The last-instar larvae of 13 species of Loxostege Hbn. are described and a key included to separate them to species. Notes on the life histories and habits have been added where these are available. One, L. sticticalis (L.), the beet webworm, often causes damage in commercial beet fields. The other species involved in this present work are: L. coloradensis (G. & R.), L. chortalis (Grt.), L. pseudobliteralis Capps, L. marculenta (G. &. R.), L. mancalis (Led.), L. helvialis (Wlk.), L. bifidalis (Fabr.), L. rantalis (Gn.), L. allectalis (Grt.), L. cereralis Zell., L. albiceralis (Grt.), and L. floridalis B. & McD.

In laboratory studies, an aqueous suspension of a commercial wettable powder formulation of Bacillus thuringiensis var. kurstaki (strain HD-1) containing at least 25 billion viable spores/g and 16000 International Units of Potency (Trichoplusia ni (Hübner))/mg prevented infestations of Indian meal moths, Plodia interpunctella (Hübner), and almond moths, Cadra cautella (Walker), in corn and wheat at a dose of ca. 120 mg of formulation/kg of grain. Treatment of a 100-mm-deep surface layer was more effective than treatments 33 or 67 mm deep and as effective as treatment of the entire grain mass Lack of uniformity in applying B. thuringiensis to the grain kernels caused a small decrease in effectiveness. Dust and bait formulations at about the same doses were as effective as the suspension, but the bait was undesirable because it supported the development of beetle larvae. The formulation was less effective in controlling the Angoumois grain moth, Sitotroga cerealella (Olivier): doses that gave complete control of the Indian meal moth and the almond moth reduced emergence of adult Angoumois grain moths by only about one-third.