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Ants represent a highly diverse and ecologically important group of insects found in almost all terrestrial ecosystems. A subset of ant species have been widely transported around the globe and invade many natural ecosystems, often out-competing native counterparts and causing varying impacts on recipient ecosystems. Decisions to control non-native ant populations require an understanding of their interactions and related impacts on native communities. We employed stable isotope analysis and metabarcoding techniques to identify potential dietary niche overlap and identify gut contents of 10 ant species found in natural ecosystems in Aotearoa New Zealand. Additionally, we looked at co-occurrence to identify potential competitive interactions among native and non-native ant species. Ants fed mainly across two trophic levels, with high dietary overlap. Relative to other ant species sampled, two non-native ant species, Linepithema humile and Technomyrmex jocosus, were found to feed at the lowest trophic level. The largest isotopic niche overlap was observed between the native Monomorium antarcticum and the invasive Ochetellus glaber, with analyses revealing a negative co-occurrence pattern. Sequence data of ant gut content identified 51 molecular operational taxonomic units, representing 22 orders and 34 families, and primarily consisting of arthropod DNA. Although we generally found high dietary overlap among species, negative occurrence between a dominant, non-native species and a ubiquitous native species indicates that species-specific interactions could be negatively impacting native ecosystems. Our research progresses and informs the currently limited knowledge around establishing protocols for metabarcoding to investigate ant diet and interactions between native and non-native ant species.

1. Although most populations of non-native species arriving in new environments fail to establish, mechanisms behind failed biological invasions are still poorly understood. 2. Propagule pressure has been found to be a dominant driver of establishment success, underpinned by processes such as stochasticity and Allee effects. While studies have revealed the presence of a component Allee effect in field populations, empirical support for demographic Allee effects has been limited. 3. We used the leaf-feeding beetle Neolema ogloblini, a biological control agent against the plant Tradescantiafluminensis, as a proxy invasive species to experimentally study the process of establishment. We investigated how the initial size of the population released affects the probability of establishment and population growth in the first season after introduction at isolated sites in New Zealand. 4. The probability of establishment was found to increase with numbers of individuals released. A significant quadratic relationship was found between population size released and per capita population growth rate; that is per capita population growth rate initially increased as population size released increased but decreased at higher population levels. 5. These results support the presence of a demographic Allee effect. However, as the influence of stochasticity (environmental and demographic) could not be completely separated from that of a demographic Allee effect, we conclude that extinction probability in the experimental populations of N. ogloblini was influenced by both a demographic Allee effect and stochasticity. 6. Our study demonstrates and supports the concept that experimental biocontrol agent releases can be used for testing hypotheses regarding invasion biology.

Insect conservation is often impeded by a lack of species-specific data leading to difficulties in assessment of conservation and threat status. Utilising specimens and records held within natural history museums may help to overcome such limitations. We used specimens and their associated data from the New Zealand Arthropod Collection to provide a comparative analysis of threatened species and their related non-threatened congeners. A range of insect groups were covered, including families from the five mega-diverse insect orders. Data on the locality, date, habitat, and morphological measurements, were recorded for nearly 25,000 specimens from 460 species, of which 31 are Threatened and 104 are At Risk. Results found the Protected Area Network provided significantly less coverage for insect species classified as Threatened or At Risk. Body size, geographical distribution, and environmental variables were not consistent predictors of the current threat classification system. There were a disproportionately large number of At Risk species found on offshore islands. The current New Zealand threat classification system, based on trends in geographical occurrence and population sizes, does not accurately reflect the conservation needs of most insect species. This has significant implications for the utility of threat assessments for insect conservation.

Functional traits quantify the distinctiveness of ecological communities and provide a theoretical basis for understanding inter-specific competition, competitive exclusion, and limiting similarity. Functional traits can also be used to evaluate the risk of exotic species and biological control agents. The generalist parasitoid Meteorus pulchricornis (Wesmael 1835) (Braconidae: Hymenoptera) was used as a case study to evaluate the potential for inter-specific competition with resident hymenopteran larval parasitoid species in New Zealand. Information on taxonomic and life history traits were collated from published and unpublished literature, while morphological traits were obtained by measuring specimens in the New Zealand Arthropod Collection. Functional trait information was gathered for 89 parasitoid species, and a hierarchical agglomeration approach was used to cluster species based on similarity. A principal component analysis identified several key traits, including host development (idiobiosis, koinobiosis), site of development (ectoparasitoid, endoparasitoid), progeny per host, the host stage attacked, and ovipositor morphology. Analysis show that M. pulchricornis has the potential to compete with a different range of species, including biocontrol agents, and endemic or native species. Functional trait information using the literature and taxonomic collections can be used to complement current risk assessment tools.

A new tribe of braconid wasps provisionally included in the Rhyssalinae, Laibaleini trib. nov., type genus Laibalea gen. nov. (type species Laibalea enigmatica sp. nov.), from Kenya and the Central African Republic, is described. A molecular dataset, with emphasis on basally derived taxa based on four gene fragments (28S D2–D3 expansion region, COI barcode, elongation factor 1-alpha and 16S ribosomal DNA), was analysed both alone and in combination with a morphological dataset. Molecular phylogenetic placement of the new species into an existing subfamily is complicated by the extreme sequence divergence of the three sequences obtained for Laibalea. In both the combined sequence analysis and the combined DNA plus morphological tree, Laibalea is recovered as a sister group to the Rhyssalinae plus all non-cyclostome lineage braconids excluding Mesostoinae, Maxfischeriinae and Aphidiinae. A consensus of morphological characters and molecular analyses suggests inclusion of Laibalea either in the otherwise principally Holarctic subfamily Rhyssalinae or perhap more basally, in the principally Gondwanan Mesostoinae s.l., although we cannot exclude the possibility that it might represent a separate basal lineage. We place Laibalea in its own tribe, provisionally included in Rhyssalinae. The DNA sequence data are presented for several genera for the first time. Avga, the type genus of Avgini, is shown not to belong to Mesostoinae s.l. or Hormiinae, but its exact relationships remain uncertain. The generic compositions of Rhyssalinae and Mesostoinae s.l. are revised. Anachyra, Apoavga, Neptihormius, Neoavga and Opiopterus are shown to belong to Mesostoinae s.s. A key to the tribes of Rhyssalinae is provided.

The New Zealand Arthropod Collection (NZAC) is the world’s largest taxonomic collection of terrestrial invertebrates from New Zealand. The NZAC policy is presented that defines the vision for the collection of being managed to the highest international standards, connected through a global infrastructure, and providing high quality, authoritative, and trusted information. The policy also provides context and guidelines for collection activities, and twenty-two objectives are outlined that will be completed over the next 5 years.

Metaspathius gorgasoma Quicke & Ward sp. n. is described from specimens collected from litter samples. It is mainly characterised by the mesoscutum being strongly declivous anteriorly, a derived mo...

The first host record for Vervoortihelconscaramozzinoi van Achterberg, 1998 is presented and additional notes on its morphology are provided and illustrated. The species is recorded as parasitizing the cerambycid beetle Stenorhopalusrubiginus in Podocarpus L’Hér ex Pers (Podocarpaceae). The metasomal carapace is shown to be sexually dimorphic and comprising 4 tergites in females but 5 in males. Some aspects of metasomal sculpture are reported as being variable and others highly consistent between individuals and differing somewhat from the original description.

International audience

A new genus of Microgastrinae parasitoid wasp endemic to New Zealand, Notogaster gen. nov. Fernández-Triana and Ward, is described, with ten new species: Notogaster avilai sp. nov., N. charlesi sp. nov., N. macdonaldae sp. nov., N. martini sp. nov., N. poultonae sp. nov., N. sucklingi sp. nov., N. toddae sp. nov., N. walkeri sp. nov., N. withersae sp. nov. and N. wornerae sp. nov. Based on some features, Notogaster resembles the genus Pholetesor Mason, although morphological and molecular data reveal they are not closely related. Notogaster is found throughout New Zealand, although many species are predominantly in the South Island. Species have been collected from a range of habitats, elevations, and collecting techniques. No host information is currently available.

The introduction of species to new regions is occurring at an increasing rate. These introductions typically consist of species that are deliberately introduced for the purposes of biological control of pests or of species that are accidentally introduced through human-mediated transport networks. Understanding the potential and actual impacts of these introduced species requires comprehensive information on their geographic distributions and biological associations. However, apart from a few well-known case studies, such information is lacking for many introduced species which severely hinders further assessment of risks and impact. A dataset is provided on host associations, geographic distributions and dates of collection for both deliberately and accidentally-introduced parasitoid wasp species (Hymenoptera) in New Zealand. Information was obtained by digitising specimens from the New Zealand Arthropod Collection. Dates of records range from 1921 to 2017. The dataset includes 1265 specimen records, representing 127 parasitoid species from 12 families, with host records for 177 host species from 61 families and eight insect orders. These data provide baseline information to help evaluate the risk from introduced parasitoids to non-target and native species.

Global changes are predicted to facilitate the introduction, establishment, and spread of species into new environments leading to potential negative impacts on local biodiversity. Evaluating the risk associated with introduced species with a high likelihood of arrival, or species that have already been introduced, is therefore increasingly important. In the present article, we outline an operational framework to provide a basis for assessing the ecological risk of introduced species in order to facilitate justifiable management decisions. The framework integrates information based on both the species and the (potential) recipient ecosystems, using existing tools to guide pest managers through the stepwise process. This enables the prediction of high-risk species and the identification of those ecosystems most vulnerable to invasion, and facilitates understanding of the potential mechanisms and magnitude of pest impacts. The framework can be applied to different invasion scenarios to evaluate the risks and impacts of species.

The endemic New Zealand cyclostome braconid wasp genus Metaspathius Brues, which was previously only known from a single specimen, an apterous female, is revised. Four new species, including three ...

International audience; Our ability to predict the identity of future invasive alien species is largely based upon knowledge of prior invasion history. Emerging alien species-those never encountered as aliens before-therefore pose a significant challenge to biosecurity interventions worldwide. Understanding their temporal trends, origins, and the drivers of their spread is pivotal to improving prevention and risk assessment tools. Here, we use a database of 45,984 first records of 16,019 established alien species to investigate the temporal dynamics of occurrences of emerging alien species worldwide. Even after many centuries of invasions the rate of emergence of new alien species is still high: Onequarter of first records during 2000-2005 were of species that had not been previously recorded anywhere as alien, though with large variation across taxa. Model results show that the high proportion of emerging alien species cannot be solely explained by increases in well-known drivers such as the amount of imported commodities from historically important source regions. Instead, these dynamics reflect the incorporation of new regions into the pool of potential alien species, likely as a consequence of expanding trade networks and environmental change. This process compensates for the depletion of the historically important source species pool through successive invasions. We estimate that 1-16% of all species on Earth, depending on the taxonomic group, qualify as potential alien species. These results suggest that there remains a high proportion of emerging alien species we have yet to encounter, with future impacts that are difficult to predict.

Insects comprise the majority of non-native animal species established around the world. However, geographic biases in knowledge hamper an overall understanding of biological invasions globally. A dataset of accidentally introduced non-native insect species established in New Zealand was compiled from databases, entomological literature, and examination of specimens in the New Zealand Arthropod Collection. For each non-native species, the first recorded location and first recorded date of detection was obtained. Excluding intentionally introduced species, there are 1477 non-native insect species successfully established in New Zealand across 16 orders, 234 families and 1017 genera. Four orders (Coleoptera, Hemiptera, Hymenoptera and Diptera) contributed 77.5% of all established insect species. Herbivores represented the largest feeding guild (47.7%), comprised of polyphagous (48.3%) or oligophagous (39.7%) species. The majority of these species originated in the Australasian (36.7%) and Palearctic regions (24.8%). Regression trees, using a binary recursive partitioning approach, found the number of international tourist arrivals, exotic vegetation cover, and regional gross domestic product were the main factors explaining spatial patterns of recently established species. Gross domestic product best explained temporal patterns of establishment over the last century. Our findings demonstrate that broad-scale analyses of non-native species have important applications for border biosecurity by providing insight into the extent of invasions. In New Zealand, the current trajectory indicates fewer non-native species are establishing annually, suggesting biosecurity efforts are being effective at reducing rates of establishment.

Lusius malfoyi n. sp. (Hymenoptera: Ichneumonidae) is described. It is an endemic New Zealand species and the first species of the genus to be described from the Australasian region.Zoobank.org:pub:21DCEA3E-C32B-4915-A02B-0212A35E496D

Although Drosophilidae and associated hymenopterous parasitoids have been the subject of much field and laboratory ecology in many parts of the world, the system has been relatively neglected in New Zealand. This study investigated the seasonality of Drosophila, Scaptodrosophila and associated hymenopterous parasitoids in Canterbury by using traps baited with banana, orange, mushrooms, other fruits and vegetables and vinegar at two locations, New Brighton and Lincoln. From 176 sampling events, seven species of drosophilid were collected: Drosophila busckii; D. funebris; D. hydei; D. immigrans; D. pseudoobscura; D. simulans; and Scaptodrosophila enigma. Seven species of adult parasitoid wasps were also recorded in the traps: the braconids Dinotrema longworthi, Aphaereta aotea, Asobara tabida, Aspilota andyaustini; the ichneumonid Campoplex sp.; and two encyrtids, including Tachinaephagus zealandicus.The more abundant drosophilid species were found throughout the year, with fewer species occurring i...

In the second paper on New Zealand Tersilochinae (Ichneumonidae) we review two endemic New Zealand genera, Kiwi gen. nov. (eight species) and Zealochus Khalaim (three species). Nine species are described as new to science: Kiwi barrattae sp. nov., K. canterberus sp. nov., K. earlyi sp. nov., K. gronous sp. nov., K. oreteus sp. nov., K. ruzelus sp. nov., K. waitakerus sp. nov., Zealochus abominosus sp. nov. and Z. stepheni sp. nov. Zealochus gauldi Khalaim is transferred to Kiwi (comb. nov.). Identification keys to species of Kiwi and Zealochus occurring in New Zealand are provided.

Alpine invertebrate populations are expected to be highly sensitive to a changing climate because temperature plays an important role in their development, reproduction, and survival. However, high levels of rarity and endemism make it particularly challenging to measure climate effects on this group because interpretation of monitoring data is undermined by high levels of spatial turnover and inter-sample variability. Functional traits may overcome this monitoring challenge by allowing generalisation across taxa based on characters that respond consistently to a changing environment. Here we evaluate whether functional traits respond more consistently and sensitively to changes in environmental conditions at different sites than species diversity metrics. Temperature and physical structure in Chionochloa grassland plots was manipulated using Open-Top-Chamber and fertility treatments, respectively. Pitfall traps were used to sample beetles from four years (2013–2016) during the austral summer at two different altitudes in Takahe Valley, Fiordland. Natural variation between years and sites had a stronger influence on the beetle community compared with temperature and nutrient treatments. The presence of complex interactive effects between treatments, different sites, and different years, indicates that the impact of changes to temperature and nutrient levels are context-specific and that landscape-level variations have a large role on structuring beetle communities. The responses of alpine beetle communities to climate change are likely to be complex, however, trait-based measures may comprise a more sensitive method for detecting generalisable change because they can be pooled over sets of species that appear rarely in the data.

There is increasing concern about the decline of pollinators worldwide. However, despite reports that pollinator declines are widespread, data are scarce and often geographically and taxonomically biased. These biases limit robust inference about any potential pollinator crisis. Non-structured and opportunistic historical specimen collection data provide the only source of historical information which can serve as a baseline for identifying pollinator declines. Specimens historically collected and preserved in museums not only provide information on where and when species were collected, but also contain other ecological information such as species interactions and morphological traits. Here, we provide a synthesis of how researchers have used historical data to identify long-term changes in biodiversity, species abundances, morphology and pollination services. Despite recent advances, we show that information on the status and trends of most pollinators is absent. We highlight opportunities and limitations to progress the assessment of pollinator declines globally. Finally, we demonstrate different approaches to analysing museum collection data using two contrasting case studies from distinct geographical regions (New Zealand and Spain) for which long-term pollinator declines have never been assessed. There is immense potential for museum specimens to play a central role in assessing the extent of the global pollination crisis. This article is part of the theme issue ‘Biological collections for understanding biodiversity in the Anthropocene’.

The Tersilochinae (Ichneumonidae) from New Zealand are revised in part, with three new endemic genera and seventeen new species described: Aotearoazeus gen. nov., A. bullivantus sp. nov., A. coronetus sp. nov., A. probles sp. nov., Barycnellus gen. nov., B. aucklandellus sp. nov., B. conlisus sp. nov., B. cuvierensis sp. nov., B. globosus sp. nov., B. robustus sp. nov., Diaparsis zealandica sp. nov., Gauldiana gen. nov., G. arantia sp. nov., G. aspiringa sp. nov., G. dubia sp. nov., G. kaweka sp. nov., G. minuta sp. nov., G. nigra sp. nov., G. rotoitia sp. nov., and G. triangulata sp. nov. Zealochus postfurcalis is transferred to the genus Gauldiana (comb. nov.). The genus Diaparsis is recorded from New Zealand for the first time. Keys to genera and species of Tersilochinae occurring in New Zealand are provided.

Biological invasions are a major threat to biological diversity, agriculture, and human health. To predict and prevent new invasions, it is crucial to develop a better understanding of the drivers of the invasion process. The analysis of 4,533 border interception events revealed that at least 51 different alien ant species were intercepted at US ports over a period of 70 years (1914-1984), and 45 alien species were intercepted entering New Zealand over a period of 68 years (1955-2013). Most of the interceptions did not originate from species' native ranges but instead came from invaded areas. In the United States, 75.7% of the interceptions came from a country where the intercepted ant species had been previously introduced. In New Zealand, this value was even higher, at 87.8%. There was an overrepresentation of interceptions from nearby locations (Latin America for species intercepted in the United States and Oceania for species intercepted in New Zealand). The probability of a species' successful establishment in both the United States and New Zealand was positively related to the number of interceptions of the species in these countries. Moreover, species that have spread to more continents are also more likely to be intercepted and to make secondary introductions. This creates a positive feedback loop between the introduction and establishment stages of the invasion process, in which initial establishments promote secondary introductions. Overall, these results reveal that secondary introductions act as a critical driver of increasing global rates of invasions.

There is increasing concern about the decline of pollinators worldwide. However, despite reports that pollinator declines are widespread, data are scarce and often geographically and taxonomically biased. These biases limit robust inference about any potential pollinator crisis. Non-structured and opportunistic historical specimen collection data provide the only source of historical information which can serve as a baseline for identifying pollinator declines. Specimens historically collected and preserved in museums not only provide information on where and when species were collected, but also contain other ecological information such as species interactions and morphological traits. Here, we provide a synthesis of how researchers have used historical data to identify long-term changes in biodiversity, species abundances, morphology and pollination services. Despite recent advances, we show that information on the status and trends of most pollinators is absent, but we highlight opportunities and limitations to progress the assessment of pollinator declines globally. Finally, we demonstrate different approaches to analysing museum collection data using two contrasting case studies from distinct geographical regions (New Zealand and Spain) for which long-term pollinator declines have never been assessed. There is immense potential for museum specimens to play a central role in assessing the extent of the global pollination crisis.

The endemic New Zealand weta is an enigmatic insect. Although the insect is well known by its distinctive name, considerable size, and morphology, many basic aspects of weta biology remain unknown. Here, we employed cultivation-independent enumeration techniques and rRNA gene sequencing to investigate the gut microbiota of the Auckland tree weta (Hemideina thoracica). Fluorescence in situ hybridisation performed on different sections of the gut revealed a bacterial community of fluctuating density, while rRNA gene-targeted amplicon pyrosequencing revealed the presence of a microbial community containing high bacterial diversity, but an apparent absence of archaea. Bacteria were further studied using full-length 16S rRNA gene sequences, with statistical testing of bacterial community membership against publicly available termite- and cockroach-derived sequences, revealing that the weta gut microbiota is similar to that of cockroaches. These data represent the first analysis of the weta microbiota and provide initial insights into the potential function of these microorganisms.

The Anomaloninae (Hymenoptera: Ichneumonidae) from New Zealand are examined and new taxa are described: Pseudospolas gen. nov., Pseudospolas dugdalei sp. nov. and Habronyx minutus sp. nov. Aphanistes kayi is transferred to the genus Habronyx forming Habronyx kayi (Gauld), comb. nov. Although widespread, all species are uncommonly collected.http://zoobank.org/urn:lsid:zoobank.org:pub:A79156BE-D27D-49E3-AD4E-2D25EAC53A64

The potential for novel pests to attack indigenous plants can be examined in non-native ranges of these plants. We used perennial native New Zealand plant species growing in botanic gardens and on public spaces in southern California to explore new associations between these plants, the bacterium Xylella fastidiosa, and its vector, the invasive insect pest, Homalodisca vitripennis (the glassy-winged sharpshooter), both of which are not yet present in New Zealand. Further, we examined the biocontrol potential of egg parasitoids against H. vitripennis on New Zealand plant hosts in southern California. We make the case for the inclusion of biocontrol as an early-response strategy against H. vitripennis should this pest invade New Zealand, and outline the steps required to make biocontrol part of a rapid-response management plan should an incursion and localized establishment occur.

Projects involving citizen scientists have greatly increased over the last decade and understanding errors associated with such projects has been identified as an important step. NatureWatch NZ is a biodiversity recording system accessible to members of the public. The “NZ wasps, ants, bees and parasitoids (Hymenoptera) project” was initiated within NatureWatch NZ in December 2012, and comparisons were analysed between these records and the known Hymenoptera fauna of the New Zealand region. Over the course of 1 year 25 members contributed 360 records from 186 taxa, including the discovery of several introduced species new to New Zealand. There was a strong geographical bias to the records, with the majority being based around the major cities. Aculeates (stinging wasps) were significantly over-represented in the NatureWatch records. Only half (55 %) of taxa were identified to species level, with a further 28 % at genus level, and 17 % identified above genus level (family, order). Furthermore, the majority (65 %) of taxa were recorded only once, and only a few taxa were recorded >5 times (top records were “Ichneumonidae”, “Hymenoptera”, Anthidium manicatum, and Apis mellifera). It is probable that these same biases also exist for many other taxonomic groups in projects operated by citizen scientists lacking set protocols. Caution should be exercised on the subsequent use, compilation, and analysis of citizen science, especially without prior examination of records and potential biases.

Kauri forest represents a major ecosystem in northern New Zealand; however, the invertebrate fauna and their ecological diversity in these forests is very poorly known. This article investigates the composition and diversity of beetle communities in two kauri forest remnants, sampled by pitfall traps each month for one year. In total 4777 beetles were caught, representing 28 families, 84 genera and 107 species. Estimates of species richness indicate there were 173 species at both sites combined. The five most abundant species contributed 71%, and the top 10 species contributed 88% of all beetles caught. The abundance, richness and composition of the beetle community were consistent throughout the year. Patterns of niche overlap also show that the same set of species co-occur throughout the year, rather than temporal partitioning of the environment on an annual time scale. This data suggests that seasonality plays a limited role in explaining the composition and diversity of beetle communities in kauri forest.

Here, we identify current high-priority issues in New Zealand entomology. These ‘critical issues’ were defined by being of national entomological interest, and in urgent need of research or attention. The issues were derived in consultation with the Entomological Society of New Zealand members and as part of a workshop at the 62nd New Zealand Entomological Society Conference. We present a list of nine priority areas (presented here without any ranking priority). These areas are: 1. conserving indigenous invertebrate diversity; 2. limiting predator pressure exerted by exotic vertebrate predators; 3. limiting the effects of invasive invertebrates, especially Vespula wasps in honeydew beech forests; understanding the influence of pesticides and pathogens on honey bees; 4. maintaining and enhancing efficient biosecurity systems to keep out invasive pests and diseases; 5. enhancing support for taxonomy; 6. enhancing entomological teaching, training and support for entomology graduates; 7. utilising the hidden ...

The Diplazontinae (Hymenoptera: Ichneumonidae) from New Zealand is examined. Three new endemic species are described: Woldstedtius dundasius sp. nov.; W. gauldius sp. nov.; and W. titirangiensis sp. nov. These are the first Woldstedtius to be described from New Zealand, and are relatively widespread, often occurring at high altitudes. The only other known Diplazontinae occurring in New Zealand is the cosmopolitan Diplazon laetatorius (Fabricius), which is commonly found throughout the country.

Microgastrine wasps are among the most species-rich and numerous parasitoids of caterpillars (Lepidoptera). They are often host-specific and thus are extensively used in biological control efforts and figure prominently in trophic webs. However, their extraordinary diversity coupled with the occurrence of many cryptic species produces a significant taxonomic impediment. We present and release the results of 8 years (2004-2011) of DNA barcoding microgastrine wasps. Currently they are the best represented group of parasitoid Hymenoptera in the Barcode of Life Data System (BOLD), a massive barcode storage and analysis data management site for the International Barcoding of Life (iBOL) program. There are records from more than 20 000 specimens from 75 countries, including 50 genera (90% of the known total) and more than 1700 species (as indicated by Barcode Index Numbers and 2% MOTU). We briefly discuss the importance of this DNA data set and its collateral information for future research in: (1) discovery of cryptic species and description of new taxa; (2) estimating species numbers in biodiversity inventories; (3) clarification of generic boundaries; (4) biological control programmes; (5) molecular studies of host-parasitoid biology and ecology; (6) evaluation of shifts in species distribution and phenology; and (7) fostering collaboration at national, regional and world levels. The integration of DNA barcoding with traditional morphology-based taxonomy, host records, and other data has substantially improved the accuracy of microgastrine wasp identifications and will significantly accelerate further studies on this group of parasitoids.

The boneseed leafroller moth Tortrix s.l. sp. ‘chyrsanthemoides’ (BSLR), originating from Western Cape Province, South African was introduced into New Zealand for the biological control (biocontrol) of a South African shrub boneseed Chrysanthemoides monilifera ssp. monilifera but has established only patchily. We investigated factors hypothesized to influence its establishment success. Field surveys and manipulative experiments ruled out climate as a factor and indicated that establishment failure was associated with predation, mainly by invasive ants of South American (Linepithema humile), and Australian (Doleromyrma darwiniana; Nylanderia sp.) origin that were attracted to invasive honeydew-secreting scale insects (Parasaissetia nigra and Saissetia oleae) found on boneseed. An exclusion experiment showed that unless invertebrate predators (mainly invasive ants and Vespula and Polistes wasps) were excluded, BSLR larvae did not survive to maturity on boneseed plants infested with scale insects. This study supports the notion that insect agents that feed externally on the host-plant are susceptible to predation in the presence of ant-tended Homoptera and that if ant-tended Homoptera are present, candidate agents should be prioritized accordingly.

Effective detection plays an important role in the surveillance and management of invasive species. Invasive ants are very difficult to eradicate and are prone to imperfect detection because of their small size and cryptic nature. Here we demonstrate the use of spatially explicit surveillance models to estimate the probability that Argentine ants (Linepithema humile) have been eradicated from an offshore island site, given their absence across four surveys and three surveillance methods, conducted since ant control was applied. The probability of eradication increased sharply as each survey was conducted. Using all surveys and surveillance methods combined, the overall median probability of eradication of Argentine ants was 0.96. There was a high level of confidence in this result, with a high Credible Interval Value of 0.87. Our results demonstrate the value of spatially explicit surveillance models for the likelihood of eradication of Argentine ants. We argue that such models are vital to give confidence in eradication programs, especially from highly valued conservation areas such as offshore islands.

The direct and indirect interactions of invasive ants with plants, insect herbivores, and Hemiptera are complex. While ant and Hemiptera interactions with native plants have been well studied, the effects of invasive ant–scale insect mutualisms on the reproductive output of invasive weeds have not. The study system consisted of Argentine ants (Linepithema humile), boneseed (Chrysanthemoides monilifera monilifera), and sap-sucking scale insects (Hemiptera: Saissetia oleae and Parasaissetia nigra), all of which are invasive in New Zealand. We examined the direct and indirect effects of Argentine ants on scale insects and other invertebrates (especially herbivores) and on plant reproductive output. Argentine ants spent one-third of their time specifically associated with scale insects in tending behaviours. The invertebrate community was significantly different between uninfested and infested plants, with fewer predators and herbivores on ant-infested plants. Herbivore damage was significantly reduced on plants with Argentine ants, but sooty mould colonisation was greater where ants were present. Herbivore damage increased when ants were excluded from plants. Boneseed plants infested with Argentine ants produced significantly more fruits than plants without ants. The increase in reproductive output in the presence of ants may be due to increased pollination as the result of pollinators being forced to relocate frequently to avoid attack by ants, resulting in an increase in pollen transfer and higher fruit/seed set. The consequences of Argentine ant invasion can be varied; not only does their invasion have consequences for maintaining biodiversity, ant invasion may also affect weed and pest management strategies.

The Argentine ant, Linepithema humile (Mayr), is an invasive species that has been associated with various negative impacts in native communities around the world. These impacts, as for other invasive ants, are principally towards native ant species, and impacts on below-ground processes such as decomposition remain largely unexplored. We investigated the relationship between Argentine ants and invertebrate fauna, litter decomposition and soil microbial activity between paired invaded and uninvaded sites at two locations in Auckland, New Zealand, where there has been no research to date on their impacts. We examined the diversity and composition of invertebrate and microorganisms communities, and differences in soil and litter components. The composition of invertebrates (Order-level, ant and beetle species) was different between invaded and uninvaded sites, with fewer ants, isopods, amphipods, and fungus-feeding beetles at the invaded sites, whereas Collembola were more abundant at the invaded sites. There were significant differences in soil chemistry, including higher carbon and nitrogen microbial biomass at uninvaded sites. Several litter components were significantly different for Macropiper excelsum. The fibre content of litter was higher, and key nutrients (e.g. nitrogen) were lower, at invaded sites, indicating less breakdown of litter at invaded sites. A greater knowledge of the history of invasion at a site would clarify variation in the impacts of Argentine ants, but their persistence in the ground litter layer may have long-term implications for soil and plant health in native ecosystems.

Two species of New Zealand Hymenoptera, a colletid bee Leioproctus nunui and a gasteruptiid Gasteruption scintillans, are considered Threatened: both are ranked Nationally Critical. Twenty taxa are At Risk, comprising two taxa that are Declining with the remainder classified as Naturally Uncommon. A further 47 taxa are Data Deficient, and 669 known species are either Not Threatened or Introduced and Naturalised.

Effective sampling and detection plays an important role in the surveillance and management of invasive species. Invasive ants are prime candidates for imperfect detection because of their small size, cryptic nature and also because of their strong association with human transportation around the globe. We examined site occupancy, colonization-extirpation dynamics and detection probability of Argentine ant populations in the Auckland region of New Zealand. Comparison of 175 sites from 2002 to 2007 shows the dynamic nature of Argentine ants, with an extirpation rate of 33% and a colonization rate of 8%. Baited vials gave relatively poor detection for Argentine ants, despite repeated sampling. If Argentine ants were present at a location, their probability of detection using baited vials was, on average, only P = 0.55 (±SE = 0.04). However, this probability depended on the duration that baited vials were left out. Detectability was highest for vials set out for three (P = 0.52–0.75) or 6 h (P = 0.53–0.82). Detection probability for visual searching was 0.895. We use these data to suggest improvements in the design of surveys for Argentine ants. Research on detection theory and its applications for surveillance and eradication is a major gap for invasive ants.

Phytophagous (plant and wood feeding) wasps are very poorly represented in New Zealand. Larvae of woodwasps in the endemic genus Moaxiphia (Xiphydriidae) develop in the wood of angiosperms, and although they appear to be widespread they are rarely collected. This paper describes Moaxiphia gourlayi Ward & Goulet sp. n. from New Zealand. New data on species distributions are presented, along with a dichotomous key to Moaxiphia in New Zealand.