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The black soldier fly (BSF) Hermetia illucens (L.) (Diptera: Stratiomyidae) has been recognized as a promising insect species for sustainable management of organic waste and by-products. Indoor breeding of BSF with artificial lighting has been proved successful, but efforts are still needed to optimize BSF reproductive output. Increasing adult density seems an option to exploit space, whereas decreasing artificial lighting duration may reduce unnecessary power consumption. This study aimed at investigating the effects of adult density (10, 25, and 50 pairs per 30 × 30 × 30 cm cage; i.e., 370, 926, and 1,852 pairs/m3), light regime (8:16, 12:12, and 16:8 [L:D] h), and their possible interactions, on some BSF life history traits relevant to reproduction. The results show that the overall BSF reproductive output increased with increasing adult density but was not affected by light regimes per se. With the highest BSF adult density tested, an average of more than 20,000 neonate larvae were produced from a cage within 10 d. At this density, increasing photoperiod increased neonate production, but also decreased the number of neonates per watt used for artificial illumination. The temporal oviposition patterns, mean individual female reproductive output, mating success, egg hatching rate, and insect survival rate were not affected by adult density or light regime as simple effects. However, the interaction between adult density and light regime was significant for the first oviposition peak, mean individual female reproductive output, and insect survival rate. The possible mechanisms behind our results are discussed.

The giant willow aphid, Tuberolachnus salignus is an invasive insect in New Zealand for which control measures are being sought due to its detrimental effects on willow cultivation and apiculture. We evaluated the biocontrol potential of the harlequin ladybird beetle, Harmoniaaxyridis, by measuring voracity and feeding preference of larvae and adults in laboratory trials. Results show that H. axyridis consumes T. salignus, with females being more voracious than males and larvae. However, H. axyridis fed T. salignus took longer to develop, gained less weight and had lower survival compared with those fed eggs of the Mediterranean flour moth, Ephestiakuehniella. In a choice test, larval and adult H. axyridis preferred the green peach aphid, Myzuspersicae, as prey item, rejecting T. salignus. We suggest that H. axyridis is likely to use T. salignus only as a facultative prey, and therefore cannot be prioritised as a potential biocontrol agent.

The sap-sucking lace bug Gargaphia decoris Drake (Hemiptera: Tingidae) is a biological control agent released in New Zealand to control the invasive small tree or shrub Solanum mauritianum Scopoli (Solanaceae). The aim of this study was to investigate the effect of temperature, photoperiod and humidity on selected G. decoris life history traits. The selected traits were measured at six different temperatures (10, 15, 20, 25, 27.5 and 30 °C), three photoperiods (L:D 6:16, 14:10 and 16:8) and two relative humidity (RH) levels (50 and 70 ± 10%). Eggs and nymphs did not survive in the 10 °C and 30 °C treatments. The net reproductive rate (R0) resulted in population growth at all temperatures, but was highest at 25 °C. Egg hatch rate was highest at L:D 8:16, and nymphal and adult survival was better at L:D 16:8. Egg hatch was higher at 50 ± 10% RH and adult survival and population growth were higher at 70 ± 10% RH. These results will help to predict the persistence of established G. decoris populations and the potential for establishment at new release sites.

Two new species of oribatid mites of the genus Pseudotocepheus (Oribatida, Otocepheidae) are described from litter and soil in New Zealand. Pseudotocepheus whanganuiensis sp. nov. differs f...

We investigated oribatid mite communities in a Sphagnum-dominated boreal peatland system characterised by a mosaic of oligotrophic and meso-eutrophic areas. We aimed to determine the relative importance of environmental factors (pH, Sphagnum nutrient content, water table level, diversity of vascular plants and bryophytes in the surrounding plant community) and spatial variation in influencing abundance, diversity and community composition of aquatic and terrestrial oribatid mites. Among environmental variables, water table level (micro-topography), pH, and K in Sphagnum tissues were the main predictors of Oribatida community structure. Aquatic species were associated with pools; two terrestrial species—Hoplophthiracarus illinoisensis and Nothrus pratensis—were associated with oligotrophic hummocks; the rest of terrestrial species were associated with dryer mesotrophic and eutrophic habitats. Low water table depth (hummocks), high local plant diversity, and high P in Sphagnum tissues were predictors of high abundance of terrestrial Oribatida. Species richness of terrestrial Oribatida was linked with low water table and high plant diversity. For aquatic Oribatida abundance, water table depth was the single most important predictor variable. Plot trophic class (its status on the peatland poor-rich gradient assigned based on plant indicator species) was also a significant predictor of terrestrial Oribatida abundance, richness, and community structure. Spatial structuring was important for terrestrial Oribatida community composition, weak (P

Infestation of willow plants by the giant willow aphid Tuberolachnus salignus (Hemiptera:Aphididae) is associated with copious deposition of sugar-rich honeydew under the plant canopy.We explored the effect of aphid honeydew on the soil biota and biochemical indicators in a twoyearfield trial. Soil samples from under aphid-infested and control willow trees, as well as samplesfrom black sooty mould spots under the aphid-infested willows were compared, soil samples beforeaphid inoculation were used as a baseline. The honeydew deposition had a positive effect on thetotal soil carbon (C), but not on the total soil nitrogen content or soil pH. Microbial biomass C, basalrespiration, number of yeast colony forming units, and the geometric mean of activities for sixenzymes were significantly higher in honeydew-affected soils than in the control treatment on bothyears. The honeydew deposition also increased soil meso-fauna abundance, especially in the blacksooty mould spots. The soil biochemical properties, which differed before and after aphidinfestation, showed considerable overlap between the first and second year post-infestation. Theresults highlight the cascading effects of T. salignus on soil biological activity and the importance ofusing a multitrophic approach to explore similar scenarios.

This study aimed to determine the suitability of several organic waste substrates to be processed by the larvae of the black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae) (BSFL) in a value-added bioconversion system. Three types of organic waste (brewer's waste, solid phase of pig manure, and semidigested grass) were tested and compared with a standard larval diet, broll (wheat middling). Larval survival and growth, chemical composition of the resulting prepupae, conversion ratios of nutrients and waste dry matter, and waste reduction rate were measured. Larval survival was high in all tested substrates. Compared with the larvae fed pig manure or semidigested grass, those fed standard diet or brewer's waste showed shorter development time, higher weight gain, and higher prepupal crude protein and crude fat content. BSFL also reduce more dry matter in the standard diet or in brewer's waste than in the other two substrates. On the other hand, larvae fed semidigested grass took 70 d to complete development and suffered fat loss. Thus, we suggest that brewer's waste is the most suitable substrate among the selected wastes for being processed by BSFL, whereas semidigested grass is an unsuitable substrate. We found that lignin had a significantly negative effect on larval growth, and emphasized the importance of applying lignin-digesting microorganisms to lignin-rich substrates being converted by BSFL. Moreover, a protein:fat:digestible carbohydrate ratio of 2:1:2 was hypothesized to benefit larval development.

We analysed species-level datasets representing Oribatida assemblages along a gradient of old-growth primary tropical forests, secondary forests, and plantation forests in Dong Nai Biosphere Reserve, Vietnam. We identified patterns in abundance, species richness and species assemblages of Oribatida, then applied taxonomic sufficiency approach to the datasets. Using three levels of higher-taxon aggregation, we evaluated whether aggregated datasets are useful in identifying ecological patterns, in comparison to species-level data. Species-level data on Oribatida assemblages clearly separated plantation forests from other forest environments; there was no significant separation between primary and secondary forests. Geographical structuring of species-level assemblages was significant, separating sites from two regions of the reserve. There was a significant concordance between multivariate ordination plots produced for species-level and aggregated (families, suborders/superfamilies) datasets, with Oribatida assemblages of plantation forests consistently separated from two other forest types. Mycobatidae (at family level) and Ceratozetoidea (at suborder/superfamily level) were indicators of plantation forests. The coarsest taxonomic resolution dataset with only four aggregated groups produced no separation of Oribatida assemblages by forest type or region. Moderate level of taxonomic aggregation applied to Oribatida community data did not cause great differences in patterns revealed by multivariate analysis, and therefore could be a valid approach to analysing the structure of tropical Oribatida assemblages. The taxonomic level of suborders and Brachypylina superfamilies appears to be the best compromise for ecological information and ease of identification. Two traits-body size and reproductive mode-were recorded for collected Oribatida species. Community-weighted mean trait value, modified Mason's index of functional divergence, and Rao's index of functional diversity were calculated for each trait in each of the sampled Oribatida assemblages. Sexual reproduction was a dominant reproductive mode in soil Oribatida and did not vary across forest types, indicating similar levels of resource limitation for this trait. For body size, lower functional divergence in plantation forests suggests less scope for niche differentiation and higher competition among different body sizes in this forest type. Use of functional traits can enhance and complement the analysis of Oribatida communities, but more data are needed on feeding- and diet-related traits in tropical Oribatida.

The lace bug, Gargaphia decoris Drake (Hemiptera: Tingidae) is a biological control agent of the South American invasive tree Solanum mauritianum Scopoli (Solanaceae). Gargaphia decoris has been established with some success in New Zealand and South Africa. In this study, we used the climatic modelling software CLIMEX (Hearne Scientific Software Pty Ltd, Australia) to assess how current and future climatic conditions might influence the geographic distribution of the biocontrol agent in these countries and worldwide. CLIMEX parameters were based on experimental data and calibrated with distribution records from the insect’s native and non-native range. In its native range, our model predicts that G. decoris could expand its distribution into northern coastal regions of Brazil, with tropical dry summer or monsoon climate. It could also expand beyond its native range into other countries with temperate and subtropical climates, as well as several regions with tropical savanna, equatorial and monsoon climate in coastal regions. In New Zealand the greatest potential for further expansion is within the North Island, and in South Africa the expansion is limited to mostly coastal areas. In a future climate change scenario (A1B, CSIRO Mk3 2090), there is a predicted reduced distribution globally, especially for Asia, Africa, and the Americas. In Europe the climatic suitability for G. decoris will increase, with an expanded potential distribution. In South Africa the potential distribution is predicted to slightly reduce, while an expansion is predicted into the colder regions of New Zealand. These models provide a useful tool to inform future releases of G. decoris and to guide monitoring efforts within and beyond release areas.

A new monotypic genus Paraphyllodispus Khaustov and Minor gen. nov. (Acari: Pygmephoroidea: Microdispidae) with type species P. vulgaris sp. nov., and new species Phyllodispus undulatus Khaustov and Minor sp. nov. and Microdispus (Microdispus) montanus Khaustov and Minor sp. nov. are described from alpine zone (1600–1900 m a.s.l.) of the Central Otago region of the South Island of New Zealand. Dolichodispus angustus (Krczal, 1959) is also recorded from New Zealand for the first time.

The role of diet supplements (honey, water or no supplements) on egg maturation, oviposition strategy and longevity of the parasitic wasp Diaeretiella rapae McIntosh (Hymenoptera: Aphidiidae) is investigated. Parasitoids feed as larvae on hosts to acquire nutrition for growth and development, and further gain additional resources during their adult stage by feeding on either host or nonhost resources. The additional resources acquired by adults can help them to increase their reproductive activity or life expectancy, or both. Diaeretiella rapae females emerge with some developed eggs and no additional resources are required for egg maturation or successful oviposition. Females are able to oviposit and produce viable offspring immediately after emergence, and the number of eggs left in the ovaries of females decreases with subsequent oviposition, suggesting that ovigeny index of D. rapae is inclined towards pro-ovigenic status. When unmated males and females are offered honey solution, females are attracted to it, whereas males display courtship and make mating attempts but then feed on honey after mating. The oviposition efficiency of female D. rapae increases by 30% when they feed on honey compared with when starved. Honey-fed D. rapae adults live significantly longer (almost twice as long) than starved adults. Honey-fed females deprived of hosts live longer than those offered hosts regularly. The positive effects of honey-feeding on longevity are greater in females than in males. Taken together, the results of the present study suggest that the provision of additional resources to adult D. rapae parasitoids could enhance their life expectancy and parasitism efficiency in biological control programmes.

Host plant cues are known to shape insect–host plant association in many insect groups. More pronounced associations are generally manifested in specialist herbivores, but little is known in generalist herbivores. We used a polyphagous native beetle from New Zealand, bronze beetle, Eucolaspis sp. ‘Hawkes Bay’ (Chrysomelidae: Eumolpinae) to explore the role of olfaction in locating host plants and local adaptation. We also tested the role of other cues in the degree of acceptance or rejection of hosts. Adult Eucolaspis beetles were attracted to fresh leaf volatiles from apple and blackberry (Rosaceae). Male and female beetles responded similarly to olfactory cues of host plants. An indication of evolutionary affiliation was observed in olfactory preferences of geographically isolated conspecific populations. We found that geographically isolated populations of the beetles differ in their olfactory responses and exhibit some degree of local adaptation. However, irrespective of geographical and ecological associations, blackberry was preferred over apple as a feeding plant, and another novel plant, bush lawyer (Rubus australis), was readily accepted by 53.25% of the tested beetles. We show that plant volatiles play an important role in host location by Eucolaspis, but the acceptance or rejection of a particular host could also involve visual and contact cues.

Sexual receptivity and mating behavior of the cabbage aphid parasitoid Diaeretiella rapae McIntosh were studied under laboratory conditions. When male and female D. rapae were paired females, males actively courted females, while females kept themselves away from males and displayed grooming behavior. Males became sexually active immediately after emergence and made mating attempts, whereas females took longer to become receptive to mating. Virgin males quickly detected female presence, resulting in a significant increase in the frequency of male courtship. Males encountered females within 5 min of pairing, and 90% of the males displayed courtship behavior by fanning their wings and chasing the female for mating. Before successful mating, males tended to approach females more often than females approached males. The time between pairing and mating in newly emerged females was longer than in 1-d-old females. The overall mating success in D. rapae was about 70%, and successful mating was largely dependent on females’ decision to mate. Unlike females, males remained sexually receptive after mating.

Two new species of oribatid mites of the monotypic genus Neophysobates (Oribatida, Tegoribatidae) from high alpine cushion fields in the Pisa Range, South Island, New Zealand are described. Neophysobates zealandicus n. sp. differs from N. monodactylus by the presence of bothridial seta with simple stalk and clavate, rounded distally head, a short adanal lyrifissure, and thickened seta pvo with attenuate tip on tarsus II. Neophysobates incrassatus n. sp. differs from N. monodactylus by the presence of bidactylous legs, three pairs of notogastral porose areas, thin rostral seta and tutorium without free tip. An identification key to the known species of Neophysobates is provided.

Parasitoid fitness depends on its ability to manipulate reproductive strategies when in competition. This study investigated the parasitism and sex allocation strategies of the parasitic wasp Diaeretiella rapae McIntosh at a range of host (Brevicoryne brassicae L.) and conspecific densities. The results suggest that D. rapae females adjust their progeny production and progeny sex ratio with changing competition. When foraging alone, female D. rapae parasitize larger number of B. brassicae nymphs when the number of available hosts is increased, but the overall proportion of parasitized hosts decreases with increase in host density. The proportion of female offspring also decreases with elevated host density. Increase in the number of female D. rapae foraging together increased total parasitism, but reduced relative contribution of each individual female. The number of female progeny decreased when multiple females competed for the same host. However, foraging experience in the presence of one or more conspecifics increased the parasitism rate and proportion of female progeny. Competing females were more active during oviposition and had shorter lives. The study suggests that both host and foundress (female parasitoid) densities have significant effect on progeny production, sex allocation, and longevity of foraging females.

A new species of Antarctozetes (Oribatida, Ceratozetoidea) is described from the soil in New Zealand based on adult morphology. Antarctozetes mariehammerae sp. nov. differs from Antarctozetes intermedius (Hammer, 1967) by the short rostral setae, very short stalks of bothridial setae, and bidentate lamellar cusps. A revised generic diagnosis is given, Antarctozetes is maintained in Punctoribatidae, although knowledge of juvenile instars is lacking. The relationship of Antarctozetes , Anellozetes, Africoribates and Kilimabates is discussed. Data on habitat and an identification key to known species of Antarctozetes in New Zealand are provided.

Due to an unfortunate turn of events, the statistical results for TS1 (F- and p-values) in Table 4 were displayed in reversed order. The correct representation of Table 4 is published here and should be treated as definitive.

The otocepheid oribatid mite genus Leptotocepheus Balogh, 1961 is recorded in the Australasian region for the first time. The taxonomic status of the genera Leptotocepheus Balogh, 1961 and Longocepheus Balogh & Mahunka,1966 is discussed, resulting in the recognition of Longocepheus as a subgenus (stat. nov.) of Leptotocepheus and the following recombinations: Leptotocepheus (Longocepheus) australis (Balogh & Mahunka, 1966) comb. nov., Leptotocepheus (Longocepheus) globosus (Grobler, 1995) comb. nov., Leptotocepheus (Longocepheus) longus (Balogh, 1961) comb. nov., Leptotocepheus (Longocepheus) youngai (Mahunka, 1984) comb. nov. A new species of Leptotocepheus (Longocepheus) is described from New Zealand, Leptotocepheus (Longocepheus) neozealandicus sp. nov., which differs from other species of the subgenus by the presence of short, slightly developed prodorsal costulae. Revised generic and subgeneric diagnoses, an identification key and distributions for the known taxa of Leptotocepheus are presented.

A new species of the genus Belloppia (Oribatida, Oppiidae) is described from New Zealand; Belloppia bella sp. nov. differs from all species of the genus by the presence of a distal row of clear barbs on the bothridial heads and the median part of the tripartite rostrum strongly protruding and distinctly longer than the lateral parts. Supplementary descriptions for two species, Belloppia wallworki Hammer, 1968 and B. shealsi Hammer, 1968 are given based on new material from New Zealand. A revised generic diagnosis and an identification key to known species of Belloppia are presented.

Mating and oviposition complement each other in parasitoid reproduction; delay in either of these activities has disparate consequences for the fitness of the parasitoid. We investigated the effects of mating and oviposition delay on parasitism rate and progeny sex ratio in a parasitic wasp Diaeretiella rapae. Egg dynamics in the ovaries of females of different ages, and females which completed different numbers of oviposition bouts were also examined. Delay in mating and oviposition adversely affected reproductive performance of both male and female D. rapae. Delayed oviposition resulted in reduced parasitism rates in both mated and unmated females. The progeny sex ratio was female-biased, but the proportion of female offspring decreased towards the end of D. rapae life. Although females emerged with developed eggs, the egg load in the ovaries of unmated and naive females initially increased then continuously decreased with age, suggesting partial resorption of eggs towards the end of a females life. Oviposition rate of unmated females was low before mating. The extent of mating delay experienced by females affected the sex ratio of their progeny, causing overproduction of males. Delayed mating did not affect the courting capacity of males, but reduced the number of their offspring and proportion of female offspring. The duration of copulation was longer in older males. The results of this study clearly indicate the importance of parasitoid age in biological control programmes, and suggests the use of 1–2 days old D. rapae for best results.

Eucolaspis sp. “Hawke's Bay” (Chrysomelidae: Eumolpinae) is a pest that inflicts huge economic loss in many organic apple (Malus domestica Borkh.) orchards in New Zealand. The timing of control methods for this pest has been shown to be crucial for success. To aid in planning control programs, we studied threshold temperature and degree-days required for the development of Eucolaspis sp. “Hawke's Bay” pupae and modeled adult emergence in the field. Pupal development was observed at three constant temperatures. Pupae required 237.0 ± 21.67 degree-days above lower threshold temperature of 4.7°C ± 0.89°C to develop into adults. The emergence of adults was modeled with these thermal values and the model was tested for accuracy with field data. The model performed well with a precision of ±4 d. The proposed phenology model has wide applicability in monitoring and planning pest control measures.

We investigated communities of oribatid mites in five peat bogs in the north-west of the East European plain. We aimed to determine the extent to which geographic factors (latitude, separation distance), local environment (Sphagnum moss species, ground water level, biogeochemistry) and local habitat complexity (diversity of vascular plants and bryophytes in the surrounding plant community) influence diversity and community composition of Oribatida. There was a significant north-to-south increase in Oribatida abundance. In the variance partitioning, spatial factors explained 33.1 % of variability in abundance across samples; none of the environmental factors were significant. Across all bogs, Oribatida species richness and community composition were similar in Sphagnum rubellum and Sphagnum magellanicum, but significantly different and less diverse in Sphagnum cuspidatum. Sphagnum microhabitat explained 52.2 % of variability in Oribatida species richness, whereas spatial variables explained only 8.7 %. There was no distance decay in community similarity between bogs with increased geographical distance. The environmental variables explained 34.9 % of the variance in community structure, with vascular plants diversity, bryophytes diversity, and ground water level all contributing significantly; spatial variables explained 15.1 % of the total variance. Overall, only 50 % of the Oribatida community variance was explained by the spatial structure and environmental variables. We discuss relative importance of spatial and local environmental factors, and make general inferences about the formation of fauna in Sphagnum bogs.

Mating frequency and the amount of sperm transferred during mating have important consequences on progeny sex ratio and fitness of haplodiploid insects. Production of female offspring may be limited by the availability of sperm for fertilizing eggs. This study examined multiple mating and its effect on fitness of the cabbage aphid parasitoid Diaeretiella rapae McIntosh (Hymenoptera: Aphidiidae). Female D. rapae mated once, whereas males mated with on average more than three females in a single day. The minimum time lag between two consecutive matings by a male was 3 min, and the maximum number of matings a male achieved in a day was eight. Sperm depletion occurred as a consequence of multiple mating in D. rapae. The number of daughters produced by females that mated with multiple-mated males was negatively correlated with the number of matings achieved by these males. Similarly, the proportion of female progeny decreased in females that mated with males that had already mated three times. Although the proportion of female progeny resulting from multiple mating decreased, the decrease was quicker when the mating occurred on the same day than when the matings occurred once per day over several days. Mating success of males initially increased after the first mating, but then males became ‘exhausted’ in later matings; their mating success decreased with the number of prior matings. The fertility of females was affected by mating with multiple-mated males. The study suggests that male mating history affects the fitness of male and female D. rapae.

1. The reproductive fitness of a parasitoid depends on its mating and ovipositing success. Virgin haplodiploid females can reproduce, but produce only males, and may diminish fitness by producing more male offspring than required. Therefore, females must decide on whether to mate or oviposit first. 2. This study was conducted to assess the mating versus ovipositing decision and its impact on the reproductive fitness of Diaeretiella rapae (Hymenoptera: Aphididae), an endoparasitoid of the cabbage aphid Brevicoryne brassicae (Hemiptera: Aphididae). 3. When newly emerged females were given a choice between mating and ovipositing, about 62% of D. rapae females preferred to mate before ovipositing. Those females who oviposited before mating parasitised only 10% of the available aphids. After mating, females superparasitised their hosts with fertilised eggs, which resulted in a highly female-biased sex ratio in the offspring. 4. Mating success was very high (91%) in the presence of hosts (cabbage aphid nymphs) compared with that in the absence of aphids. However, mating success was not influenced by the quality (size) of the hosts present in the mating arena, despite a parasitoid preference for larger hosts during oviposition. The time between pairing and mating was also shorter in the presence of host aphids. The mean number of aphids parasitised and the parasitism rate were significantly greater after mating.

Host age-dependent fitness of Diaeretiella rapae was studied on cabbage aphid Brevicoryne brassicae. When given a choice of nymphs of four different ages (1, 3, 5 and 7 days), females showed a strong preference for oviposition in older nymphs, which were also the largest in the body size, and left the majority of younger nymphs unparasitised. More than 70% of offspring emerged from 5-day and 7-day old parasitised nymphs. Parasitoids develop faster in older hosts than in younger hosts. Development time of males was shorter than females in older hosts, but the development time of males and females was similar in younger hosts. The body size of adult D. rapae was positively correlated with the age of the hosts in which they developed. The sex ratio of offspring was found to be female-biased. A higher proportion of females emerged from older hosts. D. rapae females emerged from older hosts lived significantly longer. The potential fecundity of the females emerged from older (larger in body size) hosts was significantly greater than of those emerged from younger hosts with smaller bodies. Results suggest that D. rapae preferred older hosts to maximise the reproductive fitness gain. The oviposition strategy of D. rapae is discussed in the context of efficiency of this parasitoid in biological control programmes.

Reproductive activities of naturally occurring population of Diaeretiella rapae (M'Intosh) (Hymenoptera: Aphidiinae) on Myzus persicae were studied during spring season in New Zealand. The cabbage seedlings were highly infested with the aphids (272±25 individuals/plant) with about 30% on average parasitised by D. rapae. Rate of parasitism was positively correlated with the aphid density (R 2=0.64). Adult emergence from aphid mummies was 90%, with a higher frequency of females than males. Increase in female/male sex ratio was found between early and late spring (1.1 vs. 1.8). Mating in D. rapae occurred throughout the day. Nearly half of the mating pairs collected were male–male pairs, which were especially prevalent during morning and evening while more male–female mating pairs were found during midday. Male–male mounting was probably because of low number of virgin females in morning and evening populations. About 80% females were mounted by smaller size males. Male–male mounting is discussed in...

Superparasitism (repeated oviposition in same host) indicates either a fitness benefit for the parasitoid, or an inability of ovipositing females to discriminate parasitised versus unparasitised hosts. Superparasitism in Diaeretiella rapae, the solitary endoparasitoid of cabbage aphid Brevicoryne brassicae, was studied in the laboratory. When given a choice of parasitised and unparasitised aphids, 70% of females made their attack on unparasitised hosts first, even though already-parasitised aphids were less defensive to parasitoid attack and ovipositing females had shorter host-handling time. The female superparasitised hosts during repeated attack and the large hosts were superparasitised more often than the small ones. Although superparasitised hosts carried two to five parasitoid larvae, only one larva developed into an adult. The body size of parasitoid larvae, as measured 4 days after oviposition, was affected by the total number of larvae in the host. Superparasitism strategies of D. rapae are discussed in the context of reproductive fitness.

Ethanedinitrile (EDN) is a potential alternative fumigant to methyl bromide for the phytosanitary treatment of timber and logs. Previously, adult golden-haired bark beetles (Hylurgus ligniperda) have shown high rates of tolerance to EDN, while all life stages of burnt-pine longhorn beetles (Arhopalus ferus) were highly susceptible. These results suggest that the fumigant mode of action might be species-specific and more complex than previously thought. Therefore, the anatomy of these beetles was examined to investigate potential differences in EDN toxicity related to these insect traits. The mesothoracic and fourth abdominal cuticles of 20 individuals were measured and compared across the two species. Spiracle sizes of 20 adult insects were also measured and compared across and within species. Of the two species, A. ferus had the thicker dorsal thoracic and abdominal cuticle. Adults of A. ferus had also the larger total spiracle area. These results provide important information to help explain the observed differences in EDN tolerance across the two species. Further work will test the main route of entry of EDN into the bodies of target insects and additional effects on EDN on insect behaviour.

The population structure and dynamics of bronze beetle, Eucolaspis spp., and other soil macro-invertebrates were studied in eight organic apple orchards in Hawke's Bay during spring/summer 2007-08. Orchards with high bronze beetle population densities also had higher abundance of all types of soil macro-invertebrates than orchards with low bronze beetle populations. Surface-dwelling generalist predators were more numerous (on average 53.6 versus 40.5 predators per trap) in orchards with low bronze beetle density than in orchards with high beetle density. This result was mainly due to spider numbers in pit-fall traps, which were highest during January. It may be that within orchards where surface- dwelling spiders are most abundant, these spiders may be predating upon newly emergent adult bronze beetles as they move from the soil to the apple foliage.

The effects of topographic variables (elevation above sea level, slope position, topographic (wetness) index, and global solar radiation) on mite abundances and on quantitative composition of Oribatida communities in soil and litter have been studied in six sites along a hill slope in a tropical lowland forest in the Bu Gia Map National Park, Southern Vietnam. A positive relationship existed between abundance and species richness of Oribatida in soil cores, and global solar radiation (W h m−2) which quantifies the total sun energy available to the local ecosystem. There was no significant relationship between abundance of Mesostigmata and topographic variables. The Oribatida community composition in soil and in litter was significantly different, with a large number of species unique to either litter or soil. The canonical correspondence analysis (CCA) showed that the topographic variables together explained 75 % (in litter) and 83 % (in soil) of the variation in Oribatida community structure. The species-topography relationship was globally significant in the litter, weaker in the soil; the eigenvalue of the CCA axis 1 (related to elevation and global solar radiation) was significant in both substrates. CCA ordinations identified groups of species associated with high landscape positions (hill crest, high elevation, high global solar radiation) versus species associated with low-lying landscape positions, where moisture tends to accumulate (hill footslope, low elevation, low solar radiation, high topographic index values). The importance of relief and geographical position for soil Oribatida is discussed.

A new species of oribatid mites of the genus Safrobates (Oribatida, Punctoribatidae) is described from the soil of alpine herbaceous snowbank of the Central Otago region in the South Island of New Zealand. Safrobates insignis sp. nov. differs from S. miniporus Mahunka, 1989 and S. gerdi Ermilov & Minor, 2016 in having penicillate subcapitular setae h, epimeral setae (except 1c) and aggenital setae, the presence of neotrichy on epimere I, four pairs of notogastral porose areas, six pairs of genital setae and tridactylous legs. Accessory information on Safrobates and the relevance of some morphological traits of the new species are discussed. A revised generic diagnosis is given, relationships of Safrobates, Macrogena and Magellozetes are discussed, and Magellozetes is transferred from Ceratozetidae to Punctoribatidae. An identification key to known species of Safrobates is provided.

Three new species of oribatid mites of the superfamily Oripodoidea (Acari, Oribatida) are described from the soil of alpine herbaceous snowbanks in the South Island of New Zealand. Scheloribates (Topobates) quindecim sp. nov. differs from all S. (Topobates) species by the presence of 15 pairs of notogastral setae (vs. 12–14 pairs). Paraphauloppia reducta sp. nov. differs from all Paraphauloppia species by the presence of one pair of genital setae (vs. 3–4 pairs). Reductobates perangustus sp. nov. differs from all Reductobates species by the elongate, narrow body. An identification key to known species of Reductobates is given.

Two new species of ceratozetoid oribatid mites (Acari, Oribatida, Ceratozetoidea) are described from alpine soils of the South Island of New Zealand. Magellozetes crassisetosus sp. nov. (Ceratozetidae) differs from known representatives of the genus ( M. antarcticus antarcticus (Michael, 1895), M. antarcticus traegardhi Subias 2010 and M. processus Hammer, 1962) by shorter interlamellar setae and minute tutorial cusps. Pedunculozetes ovatum sp. nov. (Chamobatidae) differs from known representatives of the genus ( P. andinus Hammer, 1962 and P. minutus Hammer, 1967) by minute interlamellar setae and short bothridial stalks. Updated generic diagnoses for Magellozetes and Pedunculozetes are provided.

Two new species of oribatid mites of the genus Dicrotegaeus (Oribatida, Cerocepheidae) are described from alpine soils of New Zealand. Dicrotegaeus mariehammerae sp. nov. shows straight lamellae distally, rostrum with a medial incision, the notogastral lateral tubercles developed, three pairs of adanal setae and triangular epimeral tubercles E4p. In Dicrotegaeus incurvus sp. nov. the anterior parts of the lamellae are curved medially, the rostrum has a strong longitudinal ridge, the notogastral lateral tubercles are absent, two pairs of adanal setae are present and the epimeral tubercles E4p are triangular. The type species, D. mirabilis Luxton, 1988 is the only other species in this genus and shows straight lamellae distally, the rostrum complex with a multiperforate projection, lateral tubercles present, two pairs of adanal setae and rectangular epimeral tubercles E4p. A new generic diagnosis and an identification key to all species of Dicrotegaeus are provided.