In a survey in 1976–79 in Botswana, more than 14000 adult ticks were collected from cattle and other domestic and wild animals and identified. Larvae and nymphs were also collected but not counted. Comparison with previous records indicates that some species, particularly Amblyomma hebraeum Koch and Boophilus decoloratus (Koch), are becoming more numerous and widespread, probably due to cattle movements and favourable climatic conditions. Haemaphysalis aciculifer Warb. was found for the first time in Botswana. The counts from complete collections of ticks from groups of three cattle are analysed, host-parasite lists are given and the results of a few acaricide resistance tests are recorded.

The collective orientation of Chortoicetes terminifera (Wlk.) migrating at night in New South Wales was studied with a radar. Measurements of the distribution of insect echoes on the radar's plan-position-indicator display provide information about the variation of both the direction and the degree of orientation with both height and time. A quantitative analysis procedure used in a detailed study of one particularly interesting series of observations is described. It was found that collective orientation occurred frequently, and that it sometimes became very well-developed. The direction of orientation remained approximately constant for long periods, but did not appear to be consistently related to any obvious directional cue; changes in direction were observed on occasions, however, and one such change was clearly associated with a change in the direction of the wind. The degree of collective orientation was a rather more variable quantity than the direction, and increases in degree were sometimes associated with increases in the number of locusts arriving at the observation site.

A single strain of Wolbachia (α-proteobacteria, Rickettsiales) was found in widespread geographical populations of each of two Phlebotomus species, within which there was no indication of ‘infectious speciation’. The two strains were identified by sequencing a fragment of wsp (a major surface protein gene), amplified by polymerase chain reaction from DNA extracted from the body parts of individual sandflies. Infection rates were high in the males and females of both sandflies, but they were lower for the B-group wPrn strain of Wolbachia in Phlebotomus perniciosus Newstead (60.3% overall) than for the A-group wPap strain in P. papatasi (Scopoli) (81.7%). Infections were frequent in the thorax, where Leishmania develops infective forms, as well as in the abdomen, where Wolbachia must infect the reproductive tissues to ensure its vertical transmission. These findings were related to knowledge of the population biology of Wolbachia in other insects, leading to the conclusion that this endosymbiont could be useful for driving transgenes through wild populations of both sandflies. This will require characterizing the cytoplasmic incompatibility phenotypes of Wolbachia–sandfly combinations, as well as estimating for them the incidence of paternal transmission and the fidelity of maternal transmission. Paternal transmission is one explanation for finding a single Wolbachia strain associated with all mitochondrial haplotypes and lineages of each sandfly species. However, this distribution pattern could also result from multiple horizontal transmissions or the failure of wsp to provide strain markers.

After the recent introduction of the pest whitefly Bemisia tabaci (Gennadius) biotype B into Australia, research was undertaken to study the parasitoids of the long established native B. tabaci and Trialeurodes vaporariorum (Westwood). The genus Encarsia species which are important biological control agents of whiteflies and hard scales. The taxonomy of the Encarsia species attacking B. tabaci and T. vaporariorum in Australia and the Pacific Islands is revised. DNA sequencing of the 28S D2 ribosomal DNA was used characterize species. Sixteen species are recognized, with 12 occurring in Australia, eight in the Pacific region, and four in both regions. All except one species (E. formosa Gahan) are new records for Australia. Four species are described as new from Australia: E. accenta & Naumann sp. n., E. adusta Schmidt & Naumann sp. n., E. oakeyensis Schmidt & Naumann sp. n., and E. ustulata Schmidt & Naumann sp. n. Diagnostic descriptions are given for all species and each species is illustrated. pictorial key is provided to allow the identification of species by non-specialists.

In studies in the Zambezi Valley of Zimbabwe, Glossina morsitans morsitans Westw. and G. pallidipes Aust. were captured on electric nets at various points around stationary targets. The distribution of flies was affected by wind direction, wind speed and the presence or absence of an attractant odour consisting of carbon dioxide and acetone. The distributions suggested that tsetse attracted to baits by visual stimuli alone fly first to a point just downwind of the baits, where the perception of odour is important in host recognition. Changes in the distribution of catches when odour was used suggested that the distributions could form useful indices of assaying attractant odours in the field. Data for Muscidae, Tabanidae, Asilidae and Hymenoptera are also presented.

Multivariate morphometric analysis (method of canonical variates) was used to compare 38 parthenogenetic lineages and three field collections of aphids of the Myzus persicae (Sulzer) group sampled on peach and tobacco in the Caserta region of southern Italy. Comparisons were also made with the morphology of lineages collected on peach in Lehonia, in central eastern Greece away from tobacco-growing regions, and on tobacco in Naphplion, in southern Greece. The lineages were measured after parthenogenetic rearing for one to three generations on the same host (potato) under constant conditions. As in previous work, the multivariate morphometric approach separated the aphids from peach from those feeding on tobacco. The life cycle category of the lineages was also examined. Almost all the lineages from peach in Caserta were holocyclic, yet the lineages from tobacco in the same region were unable to produce sexual morphs. The results suggest that tobacco-adapted and non-tobacco-adapted forms co-exist in the same region in southern Italy, not only because they colonize different host plants, but also because they have different life cycles. This is in complete contrast to the situation in peach-growing areas of northern Greece, and shows that the ecology and population structure of M. persicae is different in neighbouring counties of the Mediterranean area, even where climatic conditions and cultivated crops are similar.

Effects of the antiparasitic drug, ivermectin, on the dung beetles, Caccobius jessoensis Harold, 1867 and the rare species, Copris ochus Motschulsky, 1860 and Copris acutidens Motschulsky, 1860 were studied in laboratory and field experiments in Hokkaido, Japan. Ivermectin was detected in dung from 1 to 21 or 28 days following treatment, with a peak on the first day after treatment in two pour-on administrations (500 μg kg−1), although there were considerable differences between the two peaks. In C. jessoensis, brood balls constructed by the female were not reduced in the dung of treated cattle except for seven days after treatment in experiment 2. Also, there was no significant difference in the mean weight of brood balls between dung from treated and control cattle. However, the emergence rates were significantly reduced in dung 1–3 days after treatment. In the field study, brood balls constructed by C. jessoensis were more abundant in dung from treated cattle in experiment 1, but adult emergence was significantly reduced at one and seven days after treatments. Adult mortality of C. ochus Motschulsky at 90 days after the beginning of rearing was 11.1% in dung from control cattle with 22 brood balls constructed, whereas it was 84% in dung from treated cattle with no brood balls and/or ovipositioning. Also, in C. acutidens Motschulsky, adult mortality at 90 days after the beginning of rearing was 3.6% in dung from control cattle with 13 brood balls constructed, whereas it was 94.1% in dung from treated cattle with no brood balls or ovipositioning. The environmental risk in the use of ivermectin during breeding period of dung beetles in pasture is discussed.

Methods of breeding and manipulating Aëdes aegypti are described. Experiments on length of life were carried out with 534 mosquitos under eleven sets of conditions of atmospheric temperature and humidity. Also, 379 females were given an opportunity to suck blood under 11 sets of conditions. The following conclusions were reached :—

1. The length of life of starved mosquitos at 23°C. is very much dependent on humidity, but it cannot be directly related to saturation deficiency.

2. In these experiments there is no significant difference between the mean survivals of males and females, the former being generally longer.

3. The survival periods of fed and unfed females have a similar relation to humidity, the fed ones surviving the conditions for a longer period, irrespective of the date of feeding.

4. The effect of a change of temperature of 7°C. on the survival at 23°C. and 30°C. is much less than would be expected when the long survival period at 10°C. is considered.

5. In the absence of any efficient physiological adaptation for retarding loss of water, the females, possibly for this reason, seek a blood meal mainly in saturated air at the temperature of maximum activity.

Pineus pini has been introduced by accident into Australia and has become a pest of some importance on Pinus radiata and P. pinaster and also attacks a few other species.

The biting-habits of mosquitos in the genus Eretmapodites Theobald, as shown by 24-hour catches, display a certain uniformity in that all the species studied are essentially diurnal and bite very close to the ground, in shade. They do not enter dwellings.

When, however, two localities are compared (the Entebbe area and Bwamba County) it is found that there is a fundamental difference in behaviour. At Entebbe there is an exceedingly well-marked wave of activity before sunset. This does not occur in Bwamba, where the cycle shows no pronounced characteristics apart from its generally diurnal nature. It is shown that this difference arises from the fact that in Bwamba the first hour of biting-activity tends to be the most intense (no matter when it occurs) whereas in Entebbe the hour before sunset is almost always preferred.

One group (the E. chrysogaster group) is present in both localities. In Entebbe it shows an activity curve of the one type, and in Bwamba a curve of the other type.

It is concluded that some environmental influence must be involved. At the moment, however, no suggestion can be made concerning the nature of this influence, beyond the fact that the activity-patterns concerned are not easily explained in terms of microclimate.

The development and reproduction of 60 clones of Sitobion avenae (Fabricius), collected in the Rennes Basin, were compared on a resistant Triticum monococcum (Linnaeus) line (Tm44) and a susceptible Triticum aestivum (Linnaeus) cultivar (Arminda). All clones had lower larval survival and mean fecundity when reared on Tm44 in comparison with Arminda. They all performed equally well on Arminda whereas there was a marked and continuously distributed variation in performance parameters among clones maintained on Tm44. The plant species, from which clones originated, significantly affected aphid performances on resistant Tm44. A more detailed experiment was carried out with four clones, shown to differ in their level of fitness on Tm44. Their performances were compared on resistant (Tm44 and Tm46) and susceptible (Tm47 and Arminda) wheat genotypes. On the basis of larval development time and intrinsic rate of natural increase (rm), two types of response were distinguished among the four clones: clones Sa1 and Sa39 appeared to be less affected by Tm44 and Tm46 resistance than Sar2 and Sa48. Moreover, Tm46 was much less resistant to clone Sal than was Tm44. These results are discussed in relation to the origins of the variation in performance of S. avenae on resistant wheat, and their implications in plant breeding for resistance to S. avenae.

Brief notes are given on the distribution and habits of 42 species of Scolytidae and 34 of Platypodidae that occur as common forest insects in Ghana. A considerable number of these can be considered as beneficial insects because they do little damage but assist in the rapid break-down of dead trees and felling slash. Others are injurious mainly as timber borers, shoot borers or, generally to a lesser extent, as bark beetles and seed insects. Trachyostus ghanaensis Schedl and Doliopygus dubius (Samps.) are of outstanding importance in their constant or frequent habit of attacking the wood of living trees of commercial value; Platypus hintzi Schanf., Doliopygus conradti (Strohm.) and D. brevis (Strohm.) are probably the most important ambrosia beetle borers of newly felled timber; and Xyleborus semiopacus Eichh. has been known to destroy whole plantations of young forest trees.

Stink bugs (Heteroptera: Pentatomidae), including Nezara viridula (L.), Euschistus servus (Say), and Chinavia hilaris (Say), are economic pests in farmscapes where they move within and between closely associated crop and non-crop habitats. Thus, field edges in these farmscapes include not only crop-to-crop interfaces but also those edges adjoining non-crop habitats. We examined the influence of field edges on colonization of stink bugs in southeastern USA farmscapes composed of typical combinations of corn, peanut, and cotton. For E. servus and N. viridula, egg-to-adult development and presence of both sexes on all crops indicated that the crops served as reproductive plants. Adult C. hilaris were rarely found on corn and on crops associated with it, and they were present mainly in cotton in peanut–cotton farmscapes. Mature crop height was significantly higher for corn than for cotton and significantly higher for cotton over peanut, and an edge effect in dispersal of stink bugs into a crop was detected up to 4.6, 8.2, and 14.6 m from the crop-to-crop interface in corn, cotton, and peanut, respectively. These results suggest that stink bug dispersal into a crop decreases as crop height increases. The first stink bug-infested crop at the crop-to-crop interface was the most significant contributor of colonizing stink bugs to an adjacent crop. An edge effect in dispersal of stink bug adults was detected in corn next to non-woodlands and woodlands and in cotton adjacent to woodlands. Edge effects were never detected in side edges of peanut. Overall, our results indicate that both plant height and host plant suitability can influence edge-mediated dispersal of stink bugs at field edges.

Catches of moths in tower-mounted light traps in northern New South Wales were analysed in relation to local and synoptic weather. Catches were correlated with windspeed, relative humidity and possibly rainfall. No correlations were obtained with temperature or moon phase. Catches were more likely to occur when winds were from the east, and were associated with wind shifts. There was a significant association with the passage of depressions or troughs, but not cold fronts. The traps were considered to be poor indicators of migration associated with fronts, because these were accompanied by high winds in which trap efficiency was reduced. Stepwise multiple regressions using temperature, relative humidity, rainfall and windspeed accounted for only about 25% of the variance, much lower than in comparable studies with ground level light traps. These results are thought to indicate that the trap catches were reflecting long-distance migration, which was usually associated with disturbed weather. Back tracking with upper wind data was used to define probable sources of moths. In the spring and early summer, these sources were predominantly to the north and west of the traps, in semi-arid pastoral and subhumid cropping zones. In the late summer and autumn they were predominantly to the south and east, in the humid pastoral and forest zone. These results are discussed in relation to the migratory strategies of several important agricultural pest species.

The Artocarpus fruit fly, Bactrocera umbrosa (Fabricius) (Diptera: Tephritidae), is an oligophagous fruit pest infesting Moraceae fruits, including jackfruit (Artocarpus heterophyllus Lamarck), a fruit commodity of high value in Malaysia. The scarcity of fundamental biological, physiological and ecological information on this pest, particularly in relation to behavioural response to phytochemical lures, which are instrumental to the success of many area-wide fruit fly control and management programmes, underpins the need for studies on this much-underrated pest. The positive response of B. umbrosa males to methyl eugenol (ME), a highly potent phytochemical lure, which attracts mainly males of many Bactrocera species, was shown to increase with increasing age. As early as 7 days after emergence (DAE), ca. 22% of males had responded to ME and over 50% by 10 DAE, despite no occurrence of matings (i.e. the males were still sexually immature). Male attraction to ME peaked from 10 to 27 DAE, which corresponded with the flies’ attainment of sexual maturity. In wind-tunnel assays during the dusk courtship period, ME-fed males exhibited earlier calling activity and attracted a significantly higher percentage of virgin females compared with ME-deprived males. ME-fed males enjoyed a higher mating success than ME-deprived males at 1-day post ME feeding in semi-field assays. ME consumption also promotes aggregation behaviour in B. umbrosa males, as demonstrated in wind-tunnel and semi-field assays. We suggest that ME plays a prominent role in promoting sexual communication and enhancing mating performance of the Artocarpus fruit fly, a finding that is congruent with previous reports on the consequences of ME acquisition by other economically important Bactrocera species.

Spodoptera exempta (Wlk.) was reared for one year at three locations in Kenya: Msabaha on the coast, Nairobi, and Mbita Point on Lake Victoria. The potential yearly number of generations was 15·8 at Msabaha, 6·6 at Nairobi and 13·1 at Mbita Point. Average developmental time from egg deposition to adult emergence was 23·1, 54·9 and 27·8 days, respectively. The longest, 77·3 days, was recorded in Nairobi and the shortest, 19·4 days, at Msabaha. The survival rate varied little seasonally at the coast but was erratic inland, with some generations failing and others very successful. Larvae offered a choice of maize and stargrass (Cynodon dactylon) showed a preference for stargrass. Survival was higher on stargrass than on maize but the developmental time was longer. Mortality was highest in the larval stage. In all generations and at all locations, death was usually caused by a nuclear polyhedrosis virus. There was a positive relationship between larval mortality and rainfall, and a negative one between larval mortality and sunshine. Mating was restricted to after midnight. Females oviposited and then mated during the same night. Peak egg-laying took place before midnight, with a smaller peak at about 02·00–04·00 h.

Reference is made to the several species of scale insects which were pests on coconuts and to the Coccinellids which were introduced to combat them.

The introduction and life-history of Chilocorus nigritus is described.

The survival of the introduced Coccinellids and the part each has played in controlling the several species of scale is noted.

The habits of some indigenous Coccinellids are recorded.

The coconut-feeding Coccids of the Seychelles are listed and their economic role mentioned.

The incidence of “sooty-mould” and the species of Coccids responsible for its growth are discussed.

An estimate is made of the value of the control effected by the Coccinellids in terms of increased copra production.

The north-western European species of the vitripennis, pallipes, octonarius, triangulator, fraternus, formosus, parasitellae, metacarpalis and circumscriptus-groups of Apanteles are revised. Sixty-five species are dealt with, of which twenty-four are described as new. One species, A. exiguus (Haliday), is lifted from synonymy. Brief notes are added on North American species of the circumscriptus-group in the British Museum (Nat. Hist.) to assist their eventual correlation with the European species. Reference is also made to two species of Hypomicrogaster.

The paper describes field and laboratory investigations on the bionomics of Cephalonomia waterstoni, a Bethylid parasite of Laemophloeus spp. A table is given in which are listed all the Bethylids attacking insect pests of stored products to which reference could be found in the literature.

An infestation of Laemophloeus, associated with two “hot spots” in Manitoba wheat, which supported a large population of Cephalonomia is described.

A simple technique for the laboratory culture of Cephalonomia is described.

The life-cycle of C. waterstoni with Laemophloeus ferrugineus as host has been worked out.

The lengths of egg, larval and cocoon (prepupal and pupal) stages at combinations of 25°C, 30°C. and 60 per cent., 80 per cent. R.H. are given. The egg and larval stages are short, lasting for about six days at 25°C. and four days at 30°C.

Within the limits used, the relative humidity appears to have no effect on the duration of development at any stage. On the other hand, temperature exerts a considerable influence; the life-cycle at 30°C. is completed in two weeks but at 25°C. it takes three weeks.

Again within the limits used, the mortality appears to increase with decrease in saturation deficit. Mortality ranged from 9 per cent, at S.D. 12·7 mm. to 36·5 per cent, at S.D. 5·0 mm.

Without food or water at all combinations of 25–30°C. and 60–80 per cent. R.H. adults live for about four days, with a range of 0·5–9·5 days. There is no difference between the sexes. Unexplained contradictory results were obtained in two experiments.

With normal or paralysed host larvae available at 30°C. and 80 per cent. R.H., males live no longer than when no food or water is available but females live for about five weeks at 25°C. and 80 per cent. R.H. and for about four weeks at 30°C. and 80 per cent. R.H.

Males fed with sucrose solution at 30°C. and 80 per cent. R.H. live for several days longer than when starved : females live for the same length of time as when fed with host larvae.

The pre-oviposition period at 25°C. and 80 per cent. R.H. is about five days; at 30°C. and 80 per cent. R.H. about one and a half days.

Fecundity. At 25°C. and 80 per cent. R.H., Cephalonomia lays about 40 eggs on 30 host larvae : at 30°C. and 80 per cent. R.H., about 65 eggs on 40 larvae.

Cephalonomia females readily oviposit on larvae that have been paralysed some time previously, and can be induced to oviposit on larvae already bearing eggs.

Virgin females produce only male offspring (arrhenotoky).

Eggs are laid in groups of one, two or three (rarely four) per larva. Single eggs produce mainly females ; pairs produce mainly one male and one female ; trios produce mainly one male and two females. At 25°C. and 80 per cent. R.H. more single eggs are laid than pairs ; at 30°C. and 80 per cent. R.H. more pairs are laid than singles. This results in the production of a higher proportion of females at 25°C. than at 30°C. The incidence of trios at both temperatures is low.

C. waterstoni is equally viable on L. minutus, L. ferrugineus and L. turcicus but shows a marked preference for L. ferrugineus.

In high-altitude summer pastures, horseflies (Diptera: Tabanidae) can be a serious nuisance to livestock, as well as mechanical vectors of animal diseases such as besnoitiosis, an enzootic disease in the Pyrenees. However, the activity of horseflies in mountainous environments is poorly documented. To study the seasonality and distribution of tabanids in the Pyrenees Mountains, a sampling design was set up in two valleys on opposite sides of the mountain, one north-facing and one south-facing, along high-elevation gradients and at different distances from a water body between May and October 2011. The influence of the landscape on species richness and abundance was assessed by taking into account forested and unforested areas in 200 m radii around the trapping sites. Our findings indicated that: (1) The slope, the altitude and the size of unforested patches significantly influenced community composition of tabanids. (2) Altitude had a positive or a negative effect, depending on the species. (3) Species richness and abundance were negatively correlated with large open habitats and positively correlated with patch-shape complexity. (4) Seasonal succession of the most abundant species was observed in both valleys, with a maximum of catches at the beginning of August; however, tabanid activity ended earlier in the southern valley, which was more exposed to sunlight. (5) Philipomyia aprica, Tabanus bromius, Tabanus glaucopis and Hybomitra auripila were active from 9:00 to 19:00 h (GMT+1), with a peak of activity at midday. This paper also discusses the implications of these findings in relation to changes in horsefly distribution and their control in mountainous environments.