Shin Etsu twist-tie ropes containing the spiny bollworm (Earias insulana(Boisduval)) pheromone were tested for mating disruption in a cotton field in Israel during 1991. Two applications of the Shin Etsu rope formulation (1000 ropes/ha), containing 50 mg pheromone per rope, effectively disrupted mating of E. insulana, reduced damage to cotton bolls, and minimized the number of chemical treatments needed. The success of the mating disruption, which lasted for more than 3.5 months, was indicated by the following: 1. Reduction of trap catches in the pheromone-treated plot as compared with the control plot (commercially treated with insecticides). 2. Lower infestation of cotton bolls in the pheromone-treated as compared with the control plot. 3. Over 90% reduction in mating success in the pheromone-treated plot, as indicated by the number of mating pairs collected at night in the two plots. 4. Reduced number of insecticidal treatments applied in the pheromone-treated plot. The release rate of the pheromones was monitored by periodical gas chromatography analyses of the remaining pheromone in ropes. The half lives of the E. insulana and Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) formulations were similar, with t1/2=45-60 days. In Israel, E. insulana and P. gossypiella infest cotton fields almost simultaneously and are controlled by the same insecticides. Therefore, the control of E. insulana with pheromones is essential in order to give reasonable meaning to the commercial application of pheromones for the control of P. gossypiella, as is practised today in many cotton fields. The present study indicates that control of E. insulana by the mating disruption technique is viable.

Comparisons of infestation and damage levels by the cotton bollworms, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), Earias vittella (Fabricius) and E. insulana (Boisduval) (Lepidoptera: Noctuidae) were made in cotton fields treated with pheromones + insecticide, insecticides only, and untreated control plots, in Pakistan during the 1991 cotton season. Early to mid season control of these three pests by mating disruption in the pheromone + insecticide treated plots meant that an average reduction of 3.5 applications of insecticides was achieved when compared with the insecticide only treated plots to control the cotton pest complex. Night observations showed that there were far fewer adult moths visible in the pheromone + insecticide treated plots than in insecticide only treated plots. Adults of both sexes were much less active and did not mate as frequently as adults in the insecticide only plots.

Diparopsis watersi (Roths.) is a serious pest of the cotton crop in the Gash Delta of the eastern Sudan. The climate and method of cotton cultivation are described briefly and a general account of the incidence of D. watersi during the season is given. Earlier work in the Sudan on this bollworm was mainly centred in the Northern Province and there is little information on the history of its occurrence in the Gash Delta. The aspects of its biology considered here include its egg-laying and larval habits, and duration of the pupal stage.

The majority of eggs were laid on the younger and more accessible plant growth. The period of wandering in search of food after eclosion from the egg was of short duration with normal egg placement, the emerging larvae had little difficulty in finding suitable food, and mortality from failure to do so was low on healthy plants. Depth of pupation did not vary greatly with soil type; the majority of pupae were found within one inch of the soil surface, and none at a depth greater than three inches. Only when the soil was a heavy clay that had baked hard following the rains, did the emerging moths have difficulty in passing through it and ascending to the surface.

The proportion of larvae forming diapause pupae increased amongst field-collected larvae as the season advanced, and in successive generations bred in an insectary from the non-diapause fractions of the preceding generations, but at no time was there a complete cessation in the production of non-diapause pupae and infestations persisted as long as there was actively growing cotton. This persistent activity in the Gash Delta is contrasted with the restriction of D. watersi to a six months' season in Nigeria. The emergence of moths from diapause pupae was not completed during the season following that of pupation, but extended for at least two further seasons; approximately 35 per cent, of the total diapause pupal population was still alive and present in the soil after the first season's emergence. In any one season the emergence was bimodal, the two peaks of emergence, which were of similar magnitude, occurring in September-October and mid-November to mid-January. When diapause pupae were kept in the laboratory and thus exposed to less extreme temperatures than in the field, the emergence was distinctly unimodal, with maximum emergence during September. The bimodal emergence observed in the field is considered to be a result of external environmental factors that inhibit pupal development at certain times of year, and emergence data from diapause pupae exposed to different climatic conditions suggest that high soil temperatures are such a factor. The pattern of moth emergence from diapause pupae in the Gash Delta is compared with that found in Nigeria and Nyasaland.

Natural mortality of D. watersi is discussed, and certain larval parasites, notably an un-named species of Apanteles of the ultor Reinh. group, and Bracon brevicornis Wesm., are considered to be of importance.

The study of the biology of D. watersi has emphasised the difficulties in controlling this bollworm, and stressed the importance of attempting to destroy it in the diapause state, preferably during the “ dead ” season. It is considered that mechanical cultivation, of the soil may provide a means to that end.

Larvae of a flea-beetle, Chaetocnema arida, were found mining in the stems of young barley shoots in June 1939.

Chlorops pumilionis larvae infested barley most heavily in fields where Agriotes larvae were doing most damage. The Chlorops adults showed marked sexual dimorphism in both size and colour. The size range for this species is correlated with a proportionate size range in its parasites Coelinius niger and Stenomalus micans. Perforations 1·3 mm. in diameter in the top of a cage were sufficient for the escape of Stenomalus but not of Chlorops or Coelinius.

Lasiosina cinctipes larvae were commonly synoecious with Chlorops in barley shoots, but in some cases (5–10 per cent.) they were living without Chlorops. In these shoots the nodes were not swollen as in Chlorops infestation. Lasiosina was not attacked by the above parasites of Chlorops.

The larvae of Elachiptera cornuta infested shoots already badly damaged by other species and were accompanied by many Lasiosina larvae. Wet weather in July favours these two species. Their puparia differ in the form of the posterior spiracles. Elachiptera also occurred in maize and wheat.

Meromyza saltatrix var. nigriventris was present in stunted barley shoots in small numbers, producing swelling of the nodes very like that due to Chlorops. The summer pigmentation in both these species in Hampshire differed from that reported by Mesnil in France. Meromyza was also bred from wheat. Meromyza puparia, unlike those of Chlorops, were attached to barley sheathing-leaves by silk.

Oscinella frit larvae, infesting young sweet maize shoots at Gosden, Surrey, were either accompanied or followed by those of Aphanotrigonum trilineatum and Elachiptera. Infesting oat shoots at Long Sutton, Hampshire, Oscinella frit larvae were accompanied by larvae of Lasiosina and Camarota curvinervis. Adults of the latter emerged from stunted barley shoots in September. They showed some resemblance to flea beetles, possibly protective. Oscinella frit was also bred in small numbers from stunted wheat and barley shoots. The Chalcid, Callitula pyrrhogaster, was reared from pupae of this species found in oat shoots.

Larvae of a Muscid, Hylemyia (Phorbia) genitalis, infested a winter wheat crop in large numbers in May 1940. Tropidoscinis albipalpis, Oscinella? gracilior and Agromyza nigripes, were bred in small numbers from potted plants of this crop kept in a cage in the laboratory during the summer. Hylemyia genitalis and Agromyza (Domomyza) ambigua pupated in the soil surrounding the roots of these plants. The adults (together with a Braconxd parasite, Phaenocarpa pullata, Hal.) emerged from the soil in the following spring.

In both experimental and naturally developed colonies, Aphis fabae Scop., and Acyrthosiphon pisum (Harris) were concentrated on the upper parts of broad bean plants. A. pisum resembled Myzus persicae (Sulz.) rather than Aphis fabae by normally infesting leaves, not stems. Colonies of M. persicae were dispersed over the whole plant. In laboratory experiments, apterous adult aphids were observed walking on bean plants, and their activity was recorded in terms of their actions at each node. Moving aphids of both species tended to maintain their direction at a node although the structure of the plant does not appear to favour this. Aphids of both species changed their direction of movement more often after going onto the leaf at a node than when they stayed on the stem. M. persicae adults went upwards as often as they went down, but those of Acyrthosiphon pisum walked up more often than down and were more likely to turn round if they were moving downwards. These differences in the behaviour of active individuals would tend to produce the differences between the observed spatial distributions of the two species, although other factors, including leaf age and reproductive rates are probably more important in determining the form of aphid colonies.

The sugarcane stem weevil, Acrotomopus atropunctellus (Boheman) (Curculionidae: Molytinae: Cholini) is an important economic pest from the Northwestern region of Argentina. Analyses of the headspace volatiles produced by separated males and females revealed one male-specific compound. Its structural identification is reported here in using gas chromatography coupled with mass spectroscopy analysis and chemical micro-reactions. Besides, two laboratory olfactometry assays allowed us to propose 6-methyl-5-hepten-2-one (sulcatone) as an aggregation pheromone for this insect, being attractive to both conspecific males and females. This compound is reported for the first time as involved in the Curculionidae family communication.

In crossing experiments with Gryon triatomae Masner, reared from the eggs of Triatoma rubrofasciata (De Geer) from Singapore and India, and G. linshcostei Masner, from eggs of Linshcosteus sp. from India, only the females of G. linshcostei yielded hybrids (3.9%). G. linshcostei accepted both hosts offered separately but preferred Linshcosteus when the two were provided together; G. triatomae showed poor acceptance of Linshcosteus eggs under both sets of conditions. In view of their reproductive isolation and these and other observed differences in their behaviour, these two sibling species could be selectively introduced into other areas for biological control of Triatominae.

One gynandromorph and six intersexes of Austrosimulium bancrofti (Tayl.) are described from specimens caught in Queensland. All of the intersexes, as well as some normal flies, were infected with mermithid larvae. The infected flies rest preferentially on trees near the river's edge which would facilitate deposition of mermithids in the river. Except for a few with mature eggs, infected females had little internal abdominal structure, and most lacked ovaries.

Two toxic baits, one containing aldrin and the other containing mirex, were compared for their effectiveness in killing field colonies of Atta cephalotes (L.) and Acromyrmex octospinosus (Reich) in Trinidad, West Indies. The fate of these two toxicants within tie nests was followed by using radiolabelled bait. Of the two baits, mirex appeared to be more acceptable to both species of ant. With Acromyrmex, the ratio of living to dead fungus gardens was not affected by the bait used, whereas with Atta there was a significant difference, aldrin killing many more gardens than mirex. For both species the proportion of medium-sized workers radiolabelled was significantly greater than for the other castes, and mirex marked greater numbers of all castes than did aldrin. Greatly different proportions of Atta workers were radiolabelled in the different fungus gardens of a nest with both baits. More radioactivity was detected in the fungus gardens treated with mirex, the difference being significant for Atta but not for Acromyrmex. Mirex bait particles incorporated into the fungus gardens were significantly smaller than aldrin bait particles, indicating different degrees of comminution by the ants.

The importance of Toxoptera species as agricultural pests is briefly discussed, along with the recent discovery in Africa of T. odinae (van der Goot). Banana is recorded as an unusual new host-plant record, and a table of other hosts is presented. The genus Toxoptera is defined and a key to species given.

Cocoon-spinning larvae of the codling moth, Cydia pomonella, emit a pheromone that mediates aggregation by pupation site-seeking fifth-instar larvae. It was unknown and, thus, we tested whether the aggregation pheromone induces arrestment or attraction responses. In paired straight-tube experiment 1, fifth-instars moved faster and farther upwind toward cospecific cocoons compared to blank controls. In still-air cage experiment 2, fifth-instars selected more often as first and final choices of pupation sites those with cocooning conspecifics than those without. Finally, in Y-tube olfactometer experiment 3, fifth-instars anemotactically responded to, and preferred, side arms with cocooning conspecifics to those without. Our data provide evidence that codling moth larvae are attracted to, rather than merely arrested by, larval aggregation pheromone. These results help explain reported aggregations or clumped distributions of larvae on tree trunks, which would likely not occur if they were based merely on chance encounter of cocoon-spinning larvae by foraging larvae.

Carbon dioxide, carbon monoxide, chloroform, hydrogen, methane and nitrous oxide emissions were collected from within several mound colonies of the subterranean termite Coptotermes lacteus (Fgottatt) and the surrounding habitat of a dry sclerophyll forest in central Gippsland, Australia, following treatment of the termite mounds with mirex-treated bait blocks. All the mirex-treated colonies died within two weeks of commencing active feeding on the bait blocks. The flux measurements of the gaseous emissions were calculated before, during and after treatment with the mirex-treated decayed wood bait blocks. Carbon dioxide, methane and hydrogen all declined after colony death.

The pear thrips Taeniothrips inconsequens (Uzel) was sampled for four years in a small sugar maple Acer saccharum plantation in Centre County, Pennsylvania, USA. The life cycle of T. inconsequens was univoltine with the main period of emergence and flight from late March to mid May. Adults, eggs, and first and second instar larvae were associated with sugar maple budburst and early leaf development from late April to late May. Larval drop occurred from mid to late May. Mature second instar larvae, propupae, pupae and adults spent from June to March in the ground; development from larva to adult occurred between September and November. From March to May most (usually >90%) thrips adults and larvae sampled were T. inconsequens. No T. inconsequens males were found. In soil samples taken in spring, summer and autumn T. inconsequens were found to a depth of 50 cm but over 87% were in the top 20 cm. Almost no T. inconsequens were found in the litter layer. Large variations in T. inconsequens adult emergence and larval drop were recorded. The most important contributing factors in fluctuations of T. inconsequens populations were the length of sugar maple budburst, the degree of synchrony between thrips emergence and sugar maple budburst, and the occurence of sugar maple flowering.

The bamboo grasshopper Ceracris fasciata is regarded as a major pest species because of the damage it causes to bamboo, and its classification within the families and subfamilies of the suborder Caelifera remains unclear. Thus, we attempted to resolve these questions using molecular biology methods and analyses. Our results are as follows: (1) the complete mitochondrial genome of C. fasciata is 15,569 bp in length. The mitochondrial genome contains a standard set of 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and an A + T-rich region in the same order as those of the other analysed Caeliferan species. The putative start codon for the COX1 gene in C. fasciata is ACC, although it is not defined in other genes. The presence of tandem repeats of different sizes in the A + T-rich region may lead to size differences in other mitochondrial genomes. The mitochondrial genome of C. fasciata harbours the typical 37 genes and an A + T-rich region, and it shows similar characteristics to those of other grasshopper species. Characterization of the mitochondrial genome has enriched our knowledge of the mitochondrial genomes of Orthoptera around the world. Therefore, the phylogenetic relationships in Orthoptera can be re-examined. (2) In phylogenetic analyses, the monophyly of Orthoptera and its two suborders (Caelifera and Ensifera) has been consistently recovered based on most of the datasets selected, regardless of the optimal criteria. Our results do not support the monophyly of the subfamily Oedipodinae of Caelifera. We found that Phlaeoba albonema of the Acridinae is sorted into a clade with Ceracris in all our phylogenetic trees, and field experiments show that Phlaeoba always lives with Ceracris in the same ecotopes. Therefore, we suggest that Phlaeoba should be classified as a member of the Oedipodinae. We found that C. fasciata always clustered with Ceracris kiangsu, and both were sisters to Ceracris versicolor. Therefore, the genetic relationship between C. fasciata and C. kiangsu is closer than that between C. fasciata and C. versicolor. (3) The oldest estimated time of divergence of Ensifera in this context was determined to be 146.16 million years ago (Mya), or around the late Jurassic or early Cretaceous. We estimated that katydids (Grylloidea) likely diverged from other groups in the early Cretaceous. According to our divergence time analyses, we concluded that the ancestral Acrididae probably originated in the early Paleogene, and it is likely that the major diversification events happened at the middle Paleogene, well into the next geologic time. We estimated that crickets (Tettigoniidae) likely diverged from other groups in the early Cretaceous. Acrididae and Romaleinae group, Pyrgacrididae and Ommexechidae group, the youngest two clades we observed, were estimated to have diverged 58.79 Mya, between the middle and early Paleogene. C. versicolor is a sister to the group containing C. kiangsu and C. fasciata. First, C. versicolor diverged from the sister group (C. kiangsu + C. fasciata) around 44.81 Mya, and then the C. kiangsu and C. fasciata group separated at 43.04 Mya.

It has been found that the size of adults of the parasites Mutilla glossinae Turner and Thyridanthrax abruptus (Lw.) reared from puparia of Glossina differ with the size of the host, the puparia of the larger tsetse species, G. pallidipes Aust., producing larger parasite than the puparia of the smaller species, G. morsitans Westw. A significant relationship has been found between size of puparium (measured by puparial width) of G. morsitans and size of the parasite (measured by thoracic area and dry weight) for males of T. abruptus and males and females of M. glossinae, and it is suggested that this relationship may extend also to other species of Thyridanthrax and Mutilla that parasitise Glossina. Evidence, both from other workers and this laboratory, indicates that it is the different quantities of food supply in the hosts that affects the size of the adult parasite.

The is insufficient knowledge of arthropod communities occurring in specific microhabitats. In this study, we characterize the arthropod assemblages inhabiting burrows of the common hamster (Cricetus cricetus L.) and factors that determine their diversity and abundance. We tested the following hypotheses: (1) arthropod assemblages are associated with a particular dominant vegetation occurring in the vicinity of burrows; (2) a correlation exists between fine-scale geographic distances among burrows and assemblage dissimilarity; and (3) the type of trap influences the sampling success of captured arthropods. We found 73 morphospecies belonging to 16 families in 109 burrows, most of which were in the families Staphylinidae (Coleoptera) and Parasitidae (Arachnida: Acari: Mesostigmata). The most abundant families were Staphylinidae, Cryptophagidae (Coleoptera), Parasitidae, and Macrochelidae (Mesostigmata) (78.89%). Among the identified species, we found Aleochara irmgardis (Staphylinidae) and Poecilochirus sexclavatus (Parasitidae) which had not yet been reported in Poland, and several other rare species. Meat-baited traps captured 64.34% more individuals, which were more diverse and species-rich than the non-baited control traps, but the former was more selective for saprophages, necrophages, and coprophages. The burrows located in areas overgrown by triticale (a hybrid of wheat and rye) were inhabited by 69.86% of the identified arthropod species, and these also had the highest abundance (64.07%) in comparison with other habitats. However, differences in sample size biased our results toward and overestimate arthropods associated with this vegetation. This study underlines that the species composition detected in burrows was affected by the methods used and hamster preferences for a specific habitat rather than the geographic proximity of the burrows. More extensive sampling across multiple habitats will be necessary to confirm our findings.

The cypress bark beetle, Phloeosinus armatus, is a common element of the dying cypress tree system in East-Mediterranean countries. Adult beetles congregate for breeding on this ephemeral resource. We studied three traits that characterize this beetle's sexual behavior and linked them to its reproductive success: mating system, mate choice, and parental care. We found that the females are the ‘pioneering sex’, excavating the mating chamber. The average female is slightly larger than the male, and female and male body size is correlated, demonstrating size-assortative mating. The time it takes for a male to enter the mating chamber is positively correlated with female size and negatively correlated with its own size, which is perhaps responsible for this assortative mating. Males remain in the gallery during the period of oviposition, gradually leaving soon after the eggs hatch. The number of eggs laid and tunnel length are positively correlated with male body size. Finally, in the presence of both parents, more eggs are laid than when the female alone is present, demonstrating the important contribution of biparental care for reproductive success. We suggest that the interaction between a monogamous mating system, assortative mating, and biparental care contributes to reproductive success.

1. A new species of aphis, Aphis (Doralis) cognatella, found on Euonymus europaeus is described and compared with Aphis (Doralis) fabae, which it closely resembles. This new aphis is brown in colour and has long hairs.

2. Two individuals, intermediate in character between oviparae and sexuparae, are mentioned.

3. Transference experiments, carried out under somewhat artificial conditions, show that although the aphis is normally found on Euonymus sp., it can exist for some time on Rumex obtusifolius, R. crispus, Chenopodium album, Capsella bursapastoris, Arctium lappa, and Beta vulgaris (flower stalks), which are also host plants of A. fabae, but it does not colonise Vicia faba.

4. The sexuparae are apterous and produce males, oviparae and apterae, thus differing from A.fabae, in which there are two sexuparous forms, one an alate gynopara and the other an apterous form found on the summer hosts.

5. Olfactometer experiments give no indication of any olfactory response to the odour of E. europaeus leaves.

1. The main food hosts of Glossina swynnertoni in a district of Tanganyika appear to be (a) one or more Bovids, perhaps kudu or roan, exhibiting a close blood relationship to ox or buffalo ; (b) giraffe ; (c) pig. There is evidence that monkey or baboon is also made use of and that zebra definitely is not.

2. With regard to G. palpalis on Maboko Island, crocodile and hippopotamus are important hosts. But they are far less important than we had supposed. The majority of flies appear to have fed on some animal not yet determined.

In host specificity tests using 81 plant species from 27 families, an undescribed Chrysolina sp. completed its development only on Chrysanthemoides monilifera, a serious weed of native vegetation in Australia. Minor exploratory feeding, mostly by adults, occurred on 35 plant species. The Chrysolina sp. is restricted to the eastern Cape Province of South Africa where it occurs on Chrysanthemoides m. pisifera, a subspecies not yet recorded in Australia. Chrysanthemoides m. monilifera and C. m. rotundata, both naturalized in Australia, were accepted as hosts by Chrysolina sp., but adult emergence was lower on the latter subspecies. A climate comparison between a site location for Chrysolina sp. and stations within the Australian distribution of Chrysanthemoides monilifera has identified potential release sites that may be suitable for the insect. Chrysolina sp. was approved for release in Australia in 1989 and releases were initiated in 1990.