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Crop diversification has been proposed as a sustainable strategy for pest control in organic cereal fields. In this study aims at improving our understanding of the ecological processes related to aphid control in real farming conditions to enhance functional agrobiodiversity. We assessed the effect of genotypic (cultivar mixture) and interspecific (burclover undersowing) diversity and its stacking on cereal aphid populations, beneficial arthropods and yield. We analyzed several variables related to aphid population, parasitism rate and abundance of predators. We established 10 treatments differing in crop diversity: three single-cultivar wheat crops (Florence-Aurora (FA), Montcada (MO) and Forment (FO)) and two cultivar mixtures (FAMO and FAFO) duplicated with a burclover undersowing in five organic fields. Polycultures had a positive effect on yield. Wheat cultivars differed in aphid abundance, with FA being the most infested. The influence of genotypic diversity on aphid control was cultivar specific. FAFO significantly lowered aphid abundance and aphid density on Florence-Aurora tillers, whereas FAMO did not provide pest control. Further, a higher burclover ground cover was negatively associated with aphid abundance, particularly in the FA treatment. Therefore, the stacking of the two diversity treatments did not out-perform the implementation of a single diversity treatment. Planned diversity did not affect the abundance or richness of predators nor parasitism. Thus, our results suggest that aphid control in polycultures was related to bottom-up effects. To conclude, our study shows the potential of field research as a promising tool for designing functional multiple crop systems in real farming scenarios.

En aquest treball s’ofereix la llista detallada dels 182 tàxons i 2.836 exemplars de Scarabaeoidea (famílies Geotrupidae, Glaphyridae, Hybosoridae, Lucanidae, Scarabaeidae i Trogidae) de l’Àfrica paleàrtica. Tota la documentació associada a cadascun d’aquests espècimens es pot consultar en col·leccions en línia de l’MCNB i al portal de GBIF. Alhora, es dona informació sobre el context històric en el qual es va iniciar aquesta col·lecció i els principals recol·lectors que l’han fet possible. Dades publicades a GBIF (Doi: 10.15468/dl.3rbjve)

Although organic farming was originally promoted as an alternative farming system to address agronomic, environmental and ecological issues, its conventionalisation has led to an intensification and specialisation of production. In the light of this, several studies have questioned the environmental benefits of organic farming as well as its agronomic viability. Thus, there is a need to improve organic vegetable systems to reduce their environmental impact without affecting their productivity. To tackle this challenge, European farmers and researchers have recently started to focus on agroecological service crops (ASCs). However, few studies have simultaneously evaluated the agronomic, environmental and ecological aspects of ASC management under different European pedo-climatic conditions. We evaluated effects of the ASC management strategies—no-till roller crimping (NT-RC) and green manuring (T-GM) on cropping system performance using agronomic, environmental and ecological indicators—to exemplify the need for multidimensional analysis to understand management implications for addressing environmental and agronomic challenges. We combined the results from 11 organic vegetable field trials conducted in seven European countries over a period of 2 years to test for general trends. Our results provide solid evidence that NT-RC management across different pedo-climatic conditions in Europe enhances the activity density of ground and rove beetles and improves both the potential energy recycling within the system and weed control. However, in NT-RC plots, lower cash crop yield and quality, energetic efficiency of production and activity density of spiders were observed compared to T-GM. Synthesis and applications. Multidimensional analyses using agronomic, environmental and ecological indicators are required to understand the implications of agricultural management in agroecosystem functioning. Introducing agroecological service crops combined with the use of no-till roller crimping is a promising strategy for improving agronomic performance (e.g. fewer weeds) and reducing environmental (e.g. increasing the potentially recyclable energy) and ecological (e.g. enhancing the activity density of beneficial taxa such as ground and rove beetles) impacts. However, our study also indicates a need for agronomic and environmental improvements while promoting a wider acceptance of this strategy.

The Xerces Blue (Glaucopsyche xerces) is considered to be the first butterfly to become extinct at global scale in historical times. It was notable for its chalky lavender wings with conspicuous white spots on the ventral wings. The last individuals were collected in their restricted habitat, in the dunes near the Presidio military base in San Francisco, in 1941. To explore the demographic history of this iconic butterfly and to better understand why it went extinct, we sequenced at medium coverage the genomes of four 80 to 100-year-old Xerces Blue specimens and seven historic specimens of its closest relative, the Silvery Blue (G. lygdamus). We compared these to a novel annotated genome of the Green-Underside Blue (G. alexis). Phylogenetic relationships inferred from complete mitochondrial genomes indicate that Xerces Blue was a distinct species that diverged from the Silvery Blue lineage at least 850,000 years ago. Using nuclear genomes, we show that both species experienced population growth during the MIS 7 interglacial period, but the Xerces Blue decreased to a very low effective population size subsequently, a trend opposite to that observed in the Silvery Blue. Runs of homozygosity in the Xerces Blue were significantly greater than in the Silvery Blue, suggesting a higher incidence of inbreeding. In addition, the Xerces Blue carried a higher proportion of derived, putatively deleterious amino acid-changing alleles than the Silvery Blue. These results demonstrate that the Xerces Blue experienced more than 100 thousand years of population decline, prior to its human-induced final extinction.

Artículo que analiza el efecto en colecciones de historia natural de agentes presentes en el aire, con fotografías de secciones de museo, tablas estadísticas y tablas de mediciones., Outdoor and indoor pollutants can affect the conservation of natural history collections. As a first approach to this question, environmental acidity around specimens in the collections of the Natural Science Museum of Barcelona and Botanic Institute of Barcelona (MCNBIBB) was measured. Measurements were taken using optical sensors in a number of different places: inside and outside buildings, in storerooms, on store cases and cabinets and in containers in three collections. All acidity measurements fell within a pH range of 6.5–7.7, which suggests that the collections tested were not exposed to a dangerous acidic environment during the measurement period. Despite its outdated facilities, the Museum’s buildings and storerooms act as effective barriers against acid pollutants entering from the outside. The type of storage facilities and containers employed seems to have little impact but is still nevertheless of some relevance. Optical sensors are excellent tools for disentangling the complex spatio-temporal environments in which the MCNB-IBB collections are housed. Larger samples will be necessary if a more complete analysis is to be undertaken., The authors from IH‐CSIC acknowledge the support of the Program TOP Heritage: Technologies in Heritage Sciences from the Regional Government of Madrid (Ref. S2018/NMT‐4372), INTRODUCTION OBJECTIVES EQUIPMENT COLLECTIONS TESTED RESULTS DISCUSSION CONCLUSIONS ACKNOWLEDGMENTS AND FUNDING INFORMATION Biographies References

A new species of Limnophilinae (Diptera: Limoniidae), Dicranophragma (Brachylimnophila)relictum Mederos sp. nov., is described. This is the third species of this genus recorded from the Iberian Peninsula. This new species was discovered in a cave in the Sant Llorenç del Munt i Serra de l’Obac Natural Park, Barcelona Province (Catalonia) and it is the first record of a species of this genus from a hypogeous environment. The absence of suitable ecological conditions for the survival of this new species, particularly in the vicinity of the cave, suggests that this population of D. relictum Mederos sp. nov. is isolated. Dicranophragma relictum Mederos sp. nov. is characterized by the following features: a general grey-to-greenish-grey coloration on its thorax and a dark-grey abdomen; wings more than four times longer than wide; pale-brown-to-yellowish tinted wings, with brown veins and a well-marked stigma; in the male genitalia the upper part of the aedeagus is acute when viewed laterally and is longer than the lower part. A key is provided for separating the three species of Dicranophragma known to be present in the Iberian Peninsula.Keywords. Limnophilinae, Tipuloidea, craneflies, cave dweller, Palearctic.

1. In agricultural landscapes, arthropods provide essential ecosystem services such as biological pest control and pollination. Intensified crop management practices and homogenization of landscapes have led to declines among such organisms. Semi-natural habitats, associated with high numbers of these organisms, are increasingly lost from agricultural landscapes but diversification by increasing crop diversity has been proposed as a way to reverse observed arthropod declines and thus restore ecosystem services. However, whether or not an increase in the diversity of crop types within a landscape promotes diversity and abundances of pollinating and predaceous arthropods, and how semi-natural habitats might modify this relationship, are not well understood. 2. To test how crop diversity and the proportion of semi-natural habitats within a landscape are related to the diversity and abundance of beneficial arthropod communities , we collected primary data from seven studies focusing on natural enemies (carabids and spiders) and pollinators (bees and hoverflies) from 154 crop fields in Southern Sweden between 2007 and 2017. 3. Crop diversity within a 1-km radius around each field was positively related to the Shannon diversity index of carabid and pollinator communities in landscapes rich in semi-natural habitats. Abundances were mainly affected by the proportion of semi-natural habitats in the landscape, with decreasing carabid and increasing pollinator numbers as the proportion of this habitat type increased. Spiders showed no response to either crop diversity or the proportion of semi-natural habitats.

Col·lecció d’exemplars tipus de la subfamília Pimeliinae (Coleoptera, Tenebrionidae) dipositats al Museu de Ciències Naturals de Barcelona, Espanya S’ha organitzat, revisat i documentat la col·lecció d’espècimens tipus de la subfamília Pimeliinae (Coleoptera, Tenebrionidae) dipositats al Museu de Ciències Naturals de Barcelona. La coŀlecció està constituïda per 438 exemplars tipus, amb un total de 140 tàxons. Hi destaca la presència d’un gran nombre d’espècies de la subfamília descrites per Francesc Español, Maurice Antoine, Zoltán Kaszab i Carlo Koch. En aquest treball es facilita tota la informació disponible relacionada amb els espècimens tipus, incloent-hi per a cada taxó, espècie o subespècie la situació taxonòmica original i l’actual, la citació original del material tipus, la transcripció exacta de les etiquetes originals i l’estat de conservació dels exemplars. A més a més, es comenten les diferències existents entre la descripció original i l’etiqueta. Quan s’han produït canvis taxonòmics en l’espècie, s’inclou la bibliografia corresponent a l’apartat de referències., The type collection of the subfamily Pimeliinae (Coleoptera, Tenebrionidae) deposited in the Natural Sciences Museum of Barcelona, Spain, was organised, revised and documented. The collection contains 438 type specimens representing 140 different taxa. Of note is a considerable number of species belonging to a subfamily described by Francesc Español, Maurice Antoine, Zoltán Kaszab and Carlo Koch. In this paper we provide all the available information relating to these type specimens and for all taxa (species or subspecies) we give the following information: original and current taxonomic status, original citation of type material, the exact transcription of the original label, and the pres-ervation condition of the specimen. We also discuss the differences between the original descriptions and labels. If a taxonomic change has occurred, the references describing those changes are included at the end of the description., Colección de ejemplares tipo de la subfamilia Pimeliinae (Coleoptera, Tenebrionidae) depositados en el Museo de Ciencias Naturales de Barcelona, España Se ha organizado, revisado y documentado la colección de especímenes tipo de la subfamilia Pimeliinae (Coleoptera, Tenebrionidae) depositados en el Museo de Ciencias Naturales de Barcelona. La colección está constituida por 438 ejemplares tipo, con un total de 140 taxones. Debe destacarse la presencia de un gran número de especies de la subfamilia descritas por Francesc Español, Maurice Antoine, Zoltán Kaszab y Carlo Koch. En este trabajo se facilita toda la información disponible relacionada con los especímenes tipo. Así para cualquier taxón, especie o subespecie, se incluye la siguiente información: la situación taxonómica original y la actual, la cita original del material tipo, la transcripción exacta de las etiquetas originales y el estado de conservación de los ejemplares. Además, se comentan las diferencias existentes entre la descripción original y la etiqueta. Cuando se han producido cambios taxonómicos en la especie, en el apartado de referencias se incluye la bibliografía correspondiente.

Col·lecció d’exemplars tipus de les superfamílies Scarabaeoidea, Buprestoidea, Byrrhoidea, Elateroidea, Cleroidea, Cucujoidea, Tenebrionoidea (excepte la família Tenebrionidae), Chrysomeloidea i Curculionoidea (Coleoptera) dipositats al Museu de Ciències Naturals de Barcelona, Espanya S’ha organitzat, revisat i documentat la col·lecció d’espècimens tipus de les superfamílies Scarabaeoidea, Buprestoidea, Byrrhoidea, Elateroidea, Cleroidea, Cucujoidea, Tenebrionoidea (excepte la família Tenebrionidae), Chrysomeloidea i Curculionoidea (Coleoptera) dipositats al Museu de Ciències Naturals de Barcelona. La col·lecció està constituïda per 533 exemplars tipus, amb un total de 170 tàxons. Cal destacar la presència d’un gran nombre d’espècies de diferents famílies descrites per Francesc Español i de la família Curculionidae descrites per Manuel González. En aquest treball es facilita tota la informació disponible relacionada amb els espècimens tipus, incloent-hi per a cada taxó, espècie o subespècie la situació taxonòmica original i l’actual, la cita original del material tipus, la transcripció exacta de les etiquetes originals i l’estat de conservació dels exemplars. A més a més, es comenten les diferències existents entre la descripció original i l’etiqueta. Quan s’han produït canvis taxonòmics en l’espècie, s’inclou la bibliografia corresponent a l’apartat de referències., Colección de ejemplares tipo de las superfamilias Scarabaeoidea, Buprestoidea, Byrrhoidea, Elateroidea, Cleroidea, Cucujoidea, Tenebrionoidea (excepto la familia Tenebrionidae), Chrysomeloidea y Curculionoidea (Coleoptera) depositados en el Museo de Ciencias Naturales de Barcelona, España Se ha organizado, revisado y documentado la colección de especímenes tipo de las superfamilias Scarabaeoidea, Buprestoidea, Byrrhoidea, Elateroidea, Cleroidea, Cucujoidea, Tenebrionoidea (excepto la familia Tenebrionidae), Chrysomeloidea y Curculionoidea (Coleoptera) depositados en el Museo de Ciencias Naturales de Barcelona. Dicha colección está constituida por 533 ejemplares tipo, con un total de 170 taxones. Debe destacarse la presencia de un gran número de especies de diferentes familias descritas por Francesc Español y de la familia Curculionidae descritas por Manuel González. En este trabajo se facilita toda la información disponible relacionada con los especímenes tipo. Así para cualquier taxón, especie o subespecie, se incluye la siguiente información: la situación taxonómica original y la actual, la cita original del material tipo, la transcripción exacta de las etiquetas originales y el estado de conservación de los ejemplares. Además, se comentan las diferencias existentes entre la descripción original y la etiqueta. Cuando se han producido cambios taxonómicos en la especie, en el apartado de referencias se incluye la bibliografía correspondiente., The type collection of the superfamilies Scarabaeoidea, Buprestoidea, Byrrhoidea, Elateroidea, Cleroidea, Cucujoidea, Tenebrionoidea (except Tenebrionidae family), Chrysomeloidea and Curculionoidea (Coleoptera) deposited in the Natural Sciences Museum of Barcelona, Spain, has been organised, revised and documented. It contains 533 type specimens belonging to 170 different taxa. Of note is the considerable number of species of different families described by Francesc Español, and specimens from the Curculionidae family described by Manuel González. In this paper we provide all the available information related to these type specimens, giving the following information for each taxon, species and subspecies: the original and current taxonomic status, original citation of type materials, exact transcription of original labels, and preservation condition of specimens. Moreover, the differences between original descriptions and labels are discussed. When a taxonomic change has occurred, the references that examine these changes are included at the end of the taxa description.

Col·lecció d’exemplars tipus de les subfamílies Alleculinae, Diaperinae i Lagriinae (Coleoptera, Tenebrionidae) dipositats al Museu de Ciències Naturals de Barcelona, Espanya S’ha organitzat, revisat i documentat la col·lecció d’espècimens tipus de les subfamílies Alleculinae, Diaperinae i Lagriinae (Coleoptera, Tenebrionidae) dipositats al Museu de Ciències Naturals de Barcelona. La col·lecció està constituïda per 201 exemplars tipus, amb un total de 35 tàxons. Hi destaca la presència d’un gran nombre d’espècies d’una subfamília descrita per Francesc Español, Maurice Antoine y Zoltán Kaszab. En aquest treball es facilita tota la informació disponible relacionada amb aquests espècimens tipus i, per a tots els tàxons (espècies o subespècies), s’inclou la informació següent: la situació taxonòmica original i l’actual, la citació original del material tipus, la transcripció exacta de les etiquetes originals i l’estat de conservació dels exemplars. A més a més, es discuteixen les diferències existents entre la descripció original i l’etiqueta. Quan s’han produït canvis taxonòmics en l’espècie, s’inclou la bibliografia corresponent a l’apartat de referències., Colección de ejemplares tipo de las subfamilias Alleculinae, Diaperinae y Lagriinae (Coleoptera, Tenebrionidae) depositados en el Museo de Ciencias Naturales de Barcelona, España Se ha organizado, revisado y documentado la colección de especímenes tipo de las subfamilias Alleculinae, Diaperinae y Lagriinae (Coleoptera, Tenebrionidae) depositados en el Museo de Ciencias Naturales de Barcelona. La colección está constituida por 201 ejemplares tipo, con un total de 35 taxones. Debe destacarse la presencia de un gran número de especies de una subfamilia descrita por Francesc Español, Maurice Antoine y Zoltán Kaszab. En este trabajo se facilita toda la información disponible relacionada con estos especímenes tipo y, para todos los taxones (especies o subespecies), se incluye la siguiente información: situación taxonómica original y actual, cita original del material tipo, transcripción exacta de las etiquetas originales y estado de conservación de los ejemplares. Además, se discuten las diferencias existentes entre la descripción original y la etiqueta. Cuando se han producido cambios taxonómicos en la especie, se incluye la bibliografía correspondiente en el apartado de referencias., The type collection of the subfamilies Alleculinae, Diaperinae and Lagriinae (Coleoptera, Tenebrionidae) deposited in the Natural Sciences Museum of Barcelona, Spain, was organised, revised and documented. The collection contains 201 type specimens of 35 taxa. Of note is the number of samples froma subfamily described by Francesc Español, Maurice Antoine, and Zoltán Kaszab. In this paper, we report the information available for these type specimens and all taxa (species or subspecies). We give the following information: original and current taxonomic status, original citation of type material, the exact transcription of the original label, and the preservation condition of the specimen. We also discuss the differences between the original descriptions and labels. If a taxonomic change has occurred, the references describing those changes are included at the end of the description.

The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies., This work was supported through the National Socio-Environmental Synthesis Center (SESYNC) National Science Foundation Award DBI-1052875 for the project “Evidence and Decision-Support Tools for Controlling Agricultural Pests with Conservation Interventions” organized by D.S.K. and R.C.-K

Coŀlecció d’exemplars tipus de les famílies Dytiscidae, Histeridae, Hydraenidae i Staphylinidae dipositats al Museu de Ciències Naturals de Barcelona, Espanya. S’ha organitzat, revisat i documentat la coŀlecció d’espècimens tipus de les famílies Dytiscidae, Histeridae, Hydraenidae i Staphylinidae (Coleoptera) diposi-tats al Museu de Ciències Naturals de Barcelona. La coŀlecció està constituïda per 130 exemplars tipus, amb un total de 66 tàxons. Cal destacar-ne el gran nombre existent d’espècies hipogees de la família Staphylini-dae a causa de les descripcions d'Henri Coiffait i Francesc Español. En aquest treball es facilita tota la in-formació disponible relacionada amb els espècimens tipus, incloent-hi per a cada taxó, espècie o subespècie la situació taxonòmica original i l’actual, la citació original del material tipus, la transcripció exacta de les etiquetes originals i l’estat de conservació dels exemplars. A més a més, es comenten les diferències existents entre la descripció original i l’etiqueta. Quan s’han produït canvis taxonòmics a l’espècie, s’inclou la bibli-ografia corresponent a l’apartat de referències., Colección de ejemplares tipo de las familias Dytiscidae, Histeridae, Hydraenidae y Staphylinidae depositados en el Museo de Ciencias Naturales de Barcelona, España. Se ha organizado, revisado y documentado la colección de especímenes tipo de las familias Dytiscidae, Histeridae, Hydraenidae y Staphylinidae (Coleop-tera) depositados en el Museo de Ciencias Naturales de Barcelona. La colección está constituida por 130 ejemplares tipo, con un total de 66 taxones. Hay que destacar el gran número existente de especies hipogeas de la familia Staphylinidae debido a las descripciones de Henri Coiffait y Francesc Español. En este trabajo se facilita toda la información disponible relacionada con los especímenes tipo. Así, para cualquier taxón, especie o subespecie, se incluye la siguiente información: la situación taxonómica original y la actual, la cita original del material tipo, la transcripción exacta de las etiquetas originales y el estado de conservación de los ejemplares. Además, se comentan las diferencias existentes entre la descripción original y la etiqueta. Cuando se han producido cambios taxonómicos en la especie, se incluye la bibliografía correspondiente en el apartado de referencias., The type collection of the families Dytiscidae, Histeridae, Hydraenidae and Staphylinidae (Coleoptera) deposited in the Natural History Museum of Barcelona, Spain, has been organised, revised and documented. It contains 130 type specimens belonging to 66 different taxa. Of note is the presence of a considerable number of hypogean species of the Staphylinidae family thanks to the descriptions by Enri Coiffait and Francesc Español. In this paper we provide all the available information related to these type specimens, so for any single taxon, species or subspecies, the following information is given: the original and current taxo-nomic status, original citation of type materials, exact transcription of original labels, and preservation con-dition of specimens. Moreover, the differences between original descriptions and labels are discussed. When a taxonomic change has occurred, the references that examine those changes are included following the description of the taxa.

Cosmopolitan pests such asBrevicoryne brassicae, Lipaphis pseudobrassicae, andMyzus persicae(Aphididae) cause significant damage to Brassicaceae crops. Assessment of the important biotic and abiotic factors that regulate these pests is an essential step in the development of effective Integrated Pest Management programs for these aphids. This study evaluated the influence of leaf position, precipitation, temperature, and parasitism on populations ofL. pseudobrassicae, M. persicae, andB. brassicaein collard greens fields in the Triângulo Mineiro region (Minas Gerais state), Brazil. Similar numbers ofB. brassicaewere found on all parts of the collard green plants, whereasM. persicaeandL. pseudobrassicaewere found in greatest numbers on the middle and lower parts of the plant. While temperature and precipitation were positively related to aphid population size, their effects were not accumulative, as indicated by a negative interaction term. AlthoughDiaeretiella rapaewas the main parasitoid of these aphids, hyperparasitism was dominant; the main hyperparasitoid species recovered from plant samples wasAlloxysta fuscicornis. Parasitoids seem to have similar distributions on plants as their hosts. These results may help predict aphid outbreaks and gives clues for specific intra-plant locations when searching for and monitoring aphid populations.

1. Research relating to ecosystem services has increased, partly because of drastic declines in biodiversity in agricultural landscapes. However, the mechanistic linkages between land use, biodiversity and service provision are poorly understood and synthesized. This is particularly true for many ecosystem services provided by mobile organisms such as natural enemies to crop pests. These species are not only influenced by local land use but also by landscape composition at larger spatial scales. 2. We present a conceptual ecological production function framework for predicting land-use impact on biological control of pests by natural enemies.We develop a novel, mechanistic landscape model for biological control of cereal aphids, explicitly accounting for the influence of landscape composition on natural enemies varying in mobility, feeding rates and other life history traits. Finally, we use the model to map biological control services across cereal fields in a Swedish agricultural region with varying landscape complexity. 3. The model predicted that biological control would reduce crop damage by 45–70% and that the biological control effect would be higher in complex landscapes. In a validation with independent data, the model performed well and predicted a significant proportion of biological control variation in cereal fields.However,much variability remains to be explained, and we propose that the model could be improved by refining themechanistic understanding of predator dynamics and accounting for variation in aphid colonization. 4. We encourage scientists working with biological control to adopt the conceptual framework presented here and to develop production functions for other crop-pest systems. If this kind of ecological production function is combined with production functions for other services, the joint model will be a powerful tool for managing ecosystem services and planning for sustainable agriculture at the landscape scale.

Understanding ecosystem functioning in a farmland context by considering the variety of ecological strategies employed by arthropods is a core challenge in ecology and conservation science. We adopted a functional approach in an assessment of the relationship between three functional plant groups (grasses, broad-leaves and legumes) and the arthropod community in winter wheat fields in a Mediterranean dryland context. We sampled the arthropod community as thoroughly as possible with a combination of suction catching and flight-interception trapping. All specimens were identified to the appropriate taxonomic level (family, genus or species) and classified according to their form of feeding: chewing-herbivores, sucking-herbivores, flower-consumers, omnivores, saprovores, parasitoids or predators. We found, a richer plant community favoured a greater diversity of herbivores and, in turn, a richness of herbivores and saprovores enhanced the communities of their natural enemies, which supports the classical trophic structure hypothesis. Grass cover had a positive effect on sucking-herbivores, saprovores and their natural enemies and is probably due to grasses' ability provide, either directly or indirectly, alternative resources or simply by offering better environmental conditions. By including legumes in agroecosystems we can improve the conservation of beneficial arthropods like predators or parasitoids, and enhance the provision of ecosystem services such as natural pest control. Keywords: functional approach, plant-arthropod interaction, biological control, legumes, ecosystem services, 49 insect functional traits.

Biological control, an essential ecosystem service to agriculture, can be affected by ecological processes operating at landscape scales. Here we assessed the effect of landscape complexity, measured as propor- tion of arable land (PAL), on the abundance of aphids, parasitoids, and specialist and generalist predators. In addition we set up cage experiments to test the ability of these groups of enemies to suppress aphid den- sities. Landscape context did not significantly explain differences in aphid or parasitoid densities between fields. However, aphid densities were significantly higher in field interior compared to the margin. Coccin- ellid (specialist predator) abundance showed a similar pattern, with higher density in the field interior, indicating an aggregative response to aphid prey. In addition, Coccinellid abundance increased with PAL, but only in field interiors and not at the field margins. The abundance of carabids (generalist predators) increased with PAL, suggesting that they benefit from landscape simplification. The cage experiment revealed that specialist as well as generalist predators were able to reduce the number of aphids on barley tillers and that a combination of both guilds did not provide a greater reduction of aphids. Our results suggest higher densities of generalist predators with increasing PAL. Nonetheless, the greater abundance of coccinellids and carabid beetles in cereal fields embedded in simple landscapes does not nec- essarily imply better pest control since natural enemies may compete, thereby limiting their ability to con- trol pests.

This paper deals with the effect of the farming system on the arthropod community through its effects on plant community characteristics by comparing organic and conventional winter wheat fields in the Mediterranean region. Arthropods and plants were surveyed sequentially in each plot within each field. Most arthropods were identified to family and each taxon was classified into one of the following feeding groups: chewing-herbivores, flower-consumers, omnivores, saprophages, sucking-herbivores, parasitoids, and predators. Plant species were classified into three functional groups (grasses, forbs and legumes) which represent highly distinct resources for the arthropods. The farming system had a significant impact on the abundance and richness of grasses, forbs and legumes. In turn, the plant community, mainly conditioned by the farming system, affected the entire community of arthropods, indicating that small-scale plant community characteristics must be taken into account in order to achieve a better comprehension of the arthropod's response to the farming system. There is still no clear perception of the importance of weeds in arable ecosystems, but the role of legumes in enhancing the richness of saprophages, parasitoids and predators underlines the importance of investigating further cropping systems that combine crop production with the maintenance of essential ecosystem services.

The aphid–natural enemy interaction in winter wheat fields constitutes a complex system that has been frequently studied because of its implication for biological control. However, not all of the aphids living in cereal fields are crop pests, as there are also aphids living on weeds that may serve as alternative hosts or prey for aphid parasitoids or predators. In this context, a concomitant survey of the plant and insect communities was conducted to understand how different plant communities affect the abundance and richness of aphids and the interactions with their natural enemies. The plant community was split into functional groups (grasses, legumes and forbs), and the aphid community was divided into feeding groups according to their host preferences (specialists in grasses or forbs). The grass aphids, which dominated the total aphid catches, responded positively to grass cover, which was particularly enhanced in the conventional fields. Conversely, the forb aphids, which mainly conditioned the total species richness of the aphids, were closely correlated with the local abundance of legumes. The system of cereal aphid-parasitoids was enhanced in the conventional fields, where the abundance of grasses was higher, whereas the legumes of the organic fields indirectly played a key role in enhancing the richness of the parasitoids and the abundance of predators. Our findings indicate that a bottom-up effect exists throughout the plant community, aphids, and aphidophagous insects and that plant community characteristics should

Field survey in Catalonia (Spain) has increased the known distribution and the number of populations of the South African daisy Senecio pterophorus DC. in the Iberian Peninsula and mainland Europe. The species colonizes relatively disturbed habitats such as river beds, road borders and disturbed helm-oak communities with no limitation in light and water. The analysis of population structure related to habitat type has revealed that in riparian and ruderal areas populations are large and well-established, with a large number of members per age class. However, in disturbed forests populations have only a few scattered adults. Senecio pterophorus also shows great morphological plasticity related with habitat type: in open environments plants are shorter, adopt a spherical habit, and have smaller leaves than in forests, where they are taller and have leaves twice in size. This species may be considered as invasive in the Iberian Peninsula and mainland Europe, where it has rapidly spread in recent years. Furthermore, we suggest that S. pterophorus may be a threat to native species and habitat diversity as occurs in Australia, where the species displaces the native plants and hybridizes with some native Senecio species.