Two additional specimens of Canadaphis carpenteri Essig are described from amber in a primary site in Alberta, about 78 million years old. The rostrum is longer than previously supposed, and as siphuncular pores apparently are present, the family Canadaphididae is placed tentatively in the super-family Aphidoidea.

Photoperiodic response was studied in a pentatomid bug, Graphosoma lineatum (L.). When insects were reared from eggs under constant temperature of 26°C and long-day (18L : 6D) conditions, they developed into reproductive adults and started oviposition about 30 days after ecdysis. Short-day (12L : 12D) conditions and 26°C induced adult diapause. Both diapausing and reproductive adults displayed the photoperiodic response. Reproductive adults stopped oviposition about 10 days after the transfer to short-day conditions, and diapause adults started oviposition about 40 days after the transfer to long-day conditions.

Adults from the field were exposed either to short-day or long-day conditions. In late summer, adults that had already entered diapause responded to long-day photoperiod and started oviposition about 65 days after transfer. Thus, diapause induced under natural conditions appeared more intensive than the short-day ''laboratory'' diapause. Overwintered adults collected in spring started oviposition in both regimens about 7 days after the transfer. The absence of photoperiodic response indicated that diapause was over. However, under short-day photoperiod, females ceased oviposition about 11 days after its onset and re-entered diapause.
Czech population of G. lineatum has a facultative adult diapause induced by short-day photoperiod. The adults are sensitive to photoperiod before and in early hibernation and the completion of diapause is accompanied by a reversible loss of photoperiodic response. After a short period of oviposition the photoperiodic response is resumed. Thus, G. lineatum shows the recurrent photoperiodic response.

An ecdysteroid receptor protein has been identified and characterized from whole body extracts of Chironomus thummi larvae. The kinetic and physical characteristics of this binding are consistent with the criteria established for steroid hormone receptors and are similar to those exhibited by the Drosophila ecdysteroid receptor. The binding data of cytosols obtained from different developmental stages (third and fourth stage larvae, pupae and adults) indicate only a single type of binding site which exists throughout the life cycle of the insect with an average K_d value of 5 × 10^-9 mol/g of protein. Furthermore, single point determinations of the receptor concentration at these stages revealed that the receptor level fluctuates. This fluctuation in the receptor level corresponds well to the fluctuation in the ecdysteroid titer indicating that the number of receptors at any particular stage of development may be regulated by the presence of the moulting hormone.

Aerial netting at a height of 150 m over West Bengal during November produced evidence for extensive nocturnal migrations of a number of insect taxa, including aphids, leafhoppers, Nilaparvata lugens (the brown planthopper) and Cyrtorhinus lividipennis (a mirid predator of plant- and leafhoppers). Preliminary trajectory analysis was undertaken for aphids (particularly Lipaphis erysimi) overflying the experimental site, and it was estimated from the timing and altitude of flight, and from the winds prevailing at the time, that the long-flying individuals may have originated from sources between 100 and 300 km away to the northeast.

Service M.W.: Mosquito Ecology. Field Sampling Methods. Elsevier Science Publishers Ltd., London & New York, 1993, 988 pp.

The head is traditionally considered to be the site of production and release of the egg development neurosecretory hormone (EDNH), involved in ovarian maturation in dipterans. We find, however, that the thorax and abdomen of the mosquito Aedes aegypti each possess factors which resemble EDNH in both physiological and biochemical properties. Extracts of thoraces or abdomens each stimulated the dose-dependent appearance of ecdysteroid in incubations of A. aegypti ovaries in vitro. In addition, each extract is capable of stimulating ovarian maturation in vivo in decapitated Aedes atropalpus. The head contains higher levels of activity, absolute and specific, than either the thorax or abdomen, but extracts of all three body portions yield similar chromatographic patterns of activity. Gonadotropic activity in all three extracts elutes in two molecular weight ranges, large (approx. 6,600-7,700 MW) and small (approx. 4,150-4,250 MW). In each tissue, the small molecular weight component is more active than the large component. The roles of these non-cerebral ecdysiotropins and gonadotropins are not clear, but their similarities to cerebral EDNH suggest a function in ovarian maturation.

The intention of this study was to falsify a hypothesis of interspecific avoidance of semiochemicals from egges by ovipositing tortricid females. The oviposition responses of Cydia pomonella (L.) females to apples baited with blends of semiochemicals identified in another tortricid species, Lobesia botrana (Den. et Schiff.) were investigated. Experiments were conducted in binary choice tests using natural oviposition substrates (apples). In each experimental arena, 4 mated females were offered 16 apples (8 treated and 8 untreated) and the number of egges was compared. Females avoid ovipositing on apples treated with a blend of nine components characteristic of methanolic extracts of L. botrana eggs (fatty acids and esters) (complete blend), as well as a binary blend of palmitic acid and methyl palmitate (binary blend). Oviposition avoidance was already observed with these two blends at a dose of 72 eggs equivalent of L. botrana per apple and this effect increased with the dose. The blend of three major esters from complete blend (ternary blend) did not provoke significant avoidance. In the control, only 8.3% of apples bore no egges, this percentage was increased with complete blend and binary blend (720 Lobesia eggs) respectively up to 37.5% and 26.4%, but only to 18.1% of apples with ternary blend. Complete blend and binary blend used at high dose strongly reduced the mean number of eggs/apple on treated fruits (1.6 ± 1.8; 9 compounds) (1.8 ± 2.2; 2 compounds) against 4.6 ± 4.0 in the control. This reduction was not observed with the blend of 3 esters. It is concluded that, from the present results, apples treated with compounds associated with L. botrana eggs are avoided by C. pomonella ovipositing females. Esters alone cannot explain such an avoidance, and palmitic acid may partly cause the avoidance response.

Lepidoptera populations were monitored during 29 years by a light-trap in urban Brno. Compared with other sites in the Czech Republic (Prague-Ruzynì, Èeské Budĕjovice, Černiš) urban Brno was extraordinarily rich in species, richer than the other Czech sites studied and richer than many British sites in an urban to natural gradient. Variability of the more common species at Brno was as high as that at the ruderal/deteriorated agricultural setting at Ceske Budejovice, and generally higher than that in the wet forest environment at Cernis and much higher than in the park-like/suburban/agricultural setting of Prague. Voltinism had no effect on variability from year to year. Most of the more common species in Brno clearly increased in abundance over the years, unlike those at the other sites. Much of the large diversity at Brno, however, was because of a large number of accidental species, vagrants from elsewhere. When considering only the more common species (>= 5 individuals per year), however, Brno is among the most species-poor sites. The common species at Brno were mostly tramp species that could take advantage of whatever food and habitat the city had to offer.

Because of strong correlations in abundance between species at one site with conspecifics at other sites over distances of 150-200 km, the abundances in these populations are apparently strongly affected by large-scale processes such as weather, overriding in part large differences between the habitats or by large-scale dispersal of individuals between sites. Significant correlations also existed between conspecifics in these sites in variability as well as in trends in time, with the curious exception of Cernis, the only reasonably natural habitat, suggesting that these parameters are strongly affected by local habitat characteristics.

Clonal samples of aphids were used as the groups in canonical variate (CV) analysis, in order to compare the temperature responses of single genotypes, and thus to distinguish genotypic and environmental contributions to the phenotypic response pattern. The analysis was based on a large data set obtained by measuring 19 linear variables on adult apterae reared at four temperatures (10, 15, 20 and 26.5°C). The species used were Myzus persicae (Sulzer) and its close relative, M. antirrhinii (Macchiati). Two vectors - the scores on the first two CV's - were invariably needed to describe the temperature response. In each of three M. persicae clones, the first CV had a close linear correlation with temperature, partly corresponding to the decrease in body size at higher temperature, whereas the temperature relationship of the second CV fitted a quadratic function, being less at both high and low temperatures, and reflecting a change of ''shape'', partly comprising a relative decrease in lengths of appendages at low temperature. In M. antirrhinii the temperature relations of these two CV's was reversed, that of CV1 being quadratic and that of CV2 linear. When different genotypes of a species were combined in the same analysis, the first and second CV's still described the ''two-way'' response to temperature as for clones analysed separately, but the third and fourth CV's were totally independent of rearing temperature and separated samples according to their genotype. The consistency with which temperature effects are allocated to the first two variates seems to indicate the presence of two different aspects of the phenotypic response to temperature, perhaps reflecting different metabolic pathways by which temperature affects the pattern of growth.

Ten dominant heavy metals were analyzed in adults of the winter moth, Operophtera brumata (L.), from six sites in four isolated localities in South Bohemia. At all of the sites, metal concentrations conformed to the order Zn> Fe> Cu> Mn> Ni> Pb> Co> Cd> Cr> Hg. The highest concentration of toxic metals (lead and cadmium) was found in moths associated with trees along the main road in Plástovice (3.1 and 1.1 ppm, respectively), while it was lowest in the Èervené Blato peat bog (1.1 and 0.1 ppm, respectively). The main parasitoids were two tachinid flies, Cyzenis albicans Fall. and Phorocera obscura Fall., and one ichneumonid wasp, Agrypon flaveolatum Grav. Overall parasitism was low (2.8 and 5.9% in 1991 and 1992, respectively). The highest percentage of parasitism was on larvae in the unpolluted Èervené Blato bog (4.8 and 28.3% in 1991 and in 1992, respectively), and the lowest on apple trees along the main road in Plastovice, which was the most polluted site of the four localities.

Females of the aphid parasitoid Praon volucre were attracted to lures containing synthetic aphid sex pheromone components, particularly (+)-(4aS,7S,7aR)-nepetalactone, when these were placed on water traps in cereal fields in autumn. Trap catches were greatest at a site in S.W.England and fewest at sites in northern England 'and northern Germany, presumably due to climatic differences. Responses to the pheromones were not detected for any other cereal aphid parasitoids in the field trials, although Aphidius rhopalosiphi appears to possess olfactory receptors for (+)-(4aS,7S,7aR)-nepetalactone. A potential strategy for the use of aphid sex pheromone lures to manipulate aphid parasitoids in the field, in order to enhance their impact on aphid populations, is outlined.