Silvopastoral systems benefit invertebrate biodiversity on tropical livestock farms in Caquetá, Colombia.

In the Colombian Amazon, there has been long-term and sustained loss of primary forest threatening biodiversity and climate change mitigation. Silvopastoral practices that integrate trees into livestock production could help address both local economic and wider environmental challenges.We aimed to assess the effects of silvopastoral practices on invertebrate communities on smallholder farms in Caquetá, Colombia. Using sweep nets and malaise trapping, invertebrate communities were compared between traditional pasture, silvopasture and forest edge habitats.Invertebrate communities collected using sweep nets were contrasting among habitat types, communities were significantly different between traditional pasture and forest edge habitats and diversity and evenness were greatest in forest edges compared to traditional pastures. It appears that silvopasture areas, by supporting similar invertebrate assemblages to both traditional pasture and forest edges, may be acting as an intermediate habitat.When individual invertebrate orders were compared, Lepidoptera and Coleoptera were found in greater abundance in the forest edge habitats, while Hemiptera were more abundant in traditional pasture. Hemipterans are often pests of forage plants in pasture systems and these differences in abundance may have implications for ecosystem services and disservices.Silvopastoral approaches cannot replace the unique biodiversity supported by native forests but could deliver benefits for invertebrate conservation and ecosystem services if integrated into landscapes.

Resumen: En la Amazonía colombiana ha habido una pérdida sostenida y a largo plazo de bosque primario que amenaza la biodiversidad y la mitigación del cambio climático. Las prácticas silvopastoriles que integran los árboles en la producción ganadera podrían ayudar a abordar tanto los desafíos económicos locales como los ambientales.Nuestro objetivo fue evaluar los efectos de las prácticas silvopastoriles en comunidades de invertebrados en pequeñas fincas en Caquetá, Colombia. Las comunidades de invertebrados se compararon entre las pasturas nativas, el sistema silvopastoril y los hábitats del borde del bosque mediante el uso redes entomológicas de barrido y trampas Malaise.Las comunidades de invertebrados recolectadas usando redes entomológicas de barrido contrastaban entre los tipos de hábitat. Las comunidades eran significativamente diferentes entre las pasturas nativas y el borde de bosque. Pareciera que las áreas de silvopastoreo, al soportar conjuntos de invertebrados similares tanto a las pasturas nativas como a los bordes del bosque, pueden estar actuando como un hábitat intermedio.Cuando se compararon los órdenes individuales de invertebrados, los lepidópteros y los coleópteros se encontraron en mayor abundancia en los hábitats del borde del bosque, mientras que los hemípteros eran más abundantes en las pasturas nativas. Los hemípteros son a menudo plagas de plantas forrajeras en sistemas de pastoreo y estas diferencias en abundancia pueden tener implicaciones y perjuicios para los servicios ecosistémicos.Los sistemas silvopastoriles no pueden reemplazar la biodiversidad única apoyada por los bosques nativos, pero podrían ofrecer beneficios para la conservación de invertebrados y los servicios ecosistémicos si se integran en los paisajes.

No recovery in the biomass of flying insects over the last decade in German nature protected areas.

Five years after a German study on insect biomass described a multi-decade decline in nature protected habitats, the DINA (Diversity of Insects in Nature protected Areas) project has investigated the status of insects in 21 selected nature reserves across Germany in the years 2020 and 2021. We used the same methods and protocols for trapping and measuring the biomass of flying insects as in the earlier study. Across two vegetation periods, we accumulated a comprehensive data set of 1621 data points of two-week emptying intervals to evaluate the insect biomass along gradients from arable land into nature reserves through transects of Malaise traps. On average, we observed an increase in maximum insect biomass per day along the transect from the edge to the centre of the nature reserve. Overall, the measured insect biomass remained at low levels, consistent with previous findings from the years 2007-2016. There were no significant regional differences. The results show that protected habitats have higher insect biomass compared to farmland and are therefore essential for insects but are unlikely to be sufficient to sustain insect biodiversity. Further measures need to be taken for better protection and sustainment of insects, which fulfil key functions in all terrestrial ecosystems.

Persisting roadblocks in arthropod monitoring using non-destructive metabarcoding from collection media of passive traps.

Background: Broad-scale monitoring of arthropods is often carried out with passive traps (e.g., Malaise traps) that can collect thousands of specimens per sample. The identification of individual specimens requires time and taxonomic expertise, limiting the geographical and temporal scale of research and monitoring studies. DNA metabarcoding of bulk-sample homogenates has been found to be faster, efficient and reliable, but the destruction of samples prevents a posteriori validation of species occurrences and relative abundances. Non-destructive metabarcoding of DNA extracted from collection medium has been applied in a limited number of studies, but further tests of efficiency are required with different trap types and collection media to assess the consistency of the method. Methods: We quantified the detection rate of arthropod species when applying non-destructive DNA metabarcoding with a short (127-bp) fragment of mitochondrial COI on two combinations of passive traps and collection media: (1) water with monopropylene glycol (H2O-MPG) used in window-flight traps (WFT, 53 in total); (2) ethanol with monopropylene glycol (EtOH-MPG) used in Malaise traps (MT, 27 in total). We then compared our results with those obtained for the same samples using morphological identification (for WFTs) or destructive metabarcoding of bulk homogenate (for MTs). This comparison was applied as part of a larger study of arthropod species richness in silver fir (Abies alba Mill., 1759) stands across a range of climate-induced tree dieback levels and forest management strategies. Results: Of the 53 H2O-MPG samples from WFTs, 16 produced no metabarcoding results, while the remaining 37 samples yielded 77 arthropod MOTUs in total, of which none matched any of the 343 beetle species morphologically identified from the same traps. Metabarcoding of 26 EtOH-MPG samples from MTs detected more arthropod MOTUs (233) than destructive metabarcoding of homogenate (146 MOTUs, 8 orders), of which 71 were shared MOTUs, though MOTU richness per trap was similar between treatments. While we acknowledge the failure of metabarcoding from WFT-derived collection medium (H2O-MPG), the treatment of EtOH-based Malaise trapping medium remains promising. We conclude however that DNA metabarcoding from collection medium still requires further methodological developments and cannot replace homogenate metabarcoding as an approach for arthropod monitoring. It can be used nonetheless as a complementary treatment when enhancing the detection of soft-bodied arthropods like spiders and Diptera.

Monitoring insect biodiversity and comparison of sampling strategies using metabarcoding: A case study in the Yanshan Mountains, China.

Insects are the richest and most diverse group of animals and yet there remains a lack, not only of systematic research into their distribution across some key regions of the planet, but of standardized sampling strategies for their study. The Yanshan Mountains, being the boundary range between the Inner Mongolian Plateau and the North China Plain, present an indispensable piece of the insect biodiversity puzzle: both requiring systematic study and offering opportunities for the development of standardized methodologies. This is the first use of DNA metabarcoding to survey the insect biodiversity of the Yanshan Mountains. The study focuses on differences of community composition among samples collected via different methods and from different habitat types. In total, 74 bulk samples were collected from five habitat types (scrubland, woodland, wetland, farmland and grassland) using three collection methods (sweep netting, Malaise traps and light traps). After DNA extraction, PCR amplification, sequencing and diversity analysis were performed, a total of 7427 Operational Taxonomic Units (OTUs) at ≥97% sequence similarity level were delimited, of which 7083 OTUs were identified as belonging to Insecta. Orthoptera, Diptera, Coleoptera and Hemiptera were found to be the dominant orders according to community composition analysis. Nonmetric multidimensional scaling (NMDS) analysis based on Bray-Curtis distances revealed highly divergent estimates of insect community composition among samples differentiated by the collection method (R = .524802, p = .001), but nonsignificant difference among samples differentiated according to habitat (R = .051102, p = .078). The study therefore appears to indicate that the concurrent use of varied collection methods is essential to the accurate monitoring of insect biodiversity.

Dispersal patterns of oribatid mites across habitats and seasons.

Oribatid mites are tiny arthropods that are common in all soils of the world; however, they also occur in microhabitats above the soil such as lichens, mosses, on the bark of trees and in suspended soils. For understanding oribatid mite community structure, it is important to know whether they are dispersal limited. The aim of this study was to investigate the importance of oribatid mite dispersal using Malaise traps to exclude sole passive wind-dispersal. Oribatid mite communities were collected over a 3-year period from five habitat types (coniferous forests, deciduous forests, mixed forests, meadows, bog/heathlands sites) and three seasons (spring, summer, autumn) in Sweden. Mites entered traps either by walking or by phoresy, i.e., by being attached to flying insects. We hypothesized (1) that oribatid mite communities in the traps differ between habitats, indicating habitat-limited dispersal, and (2) that oribatid mite communities differ among seasons suggesting that dispersal varies due to changing environmental conditions such as moisture or resource availability. The majority of the collected species were not typically soil-living species but rather from habitats such as trees, lichens and mosses (e.g., Carabodes labyrinthicus, Cymbaeremaeus cymba, Diapterobates humeralis and Phauloppia lucorum) indicating that walking into the traps or entering them via phoresy are of greater importance for aboveground than for soil-living species. Overall, oribatid mite communities collected in the traps likely originated from the surrounding local habitat suggesting that long distance dispersal of oribatid mites is scarce. Significant differences among seasons indicate higher dispersal during warm and dry periods of the year. Notably, 16 species of oribatid mites collected in our study were sampled for the first time in Sweden. This study also demonstrates that Malaise traps are a meaningful tool to investigate spatial and temporal patterns of oribatid mite communities.

Diversity and abundance of tabanids in Northern Spain.

Tabanids (Diptera: Tabanidae) are large haematophagous flies that cause both direct (by biting nuisance) and indirect (primarily by mechanical transmission of diseases) damage to host species. Research studies on this family have received little attention in some parts of Europe. Our aims were to characterise the species richness, abundance, and peak of activity of tabanid fly species in a region of Northern Spain. Home-made canopy traps, sweep nets, and Malaise traps were employed for the collection of tabanids across four cattle farms, two equestrian centres, and two golf courses during a 3-month period in the summer of 2020. A total of 300 specimens of 27 tabanid species belonging to eight genera were identified. The most prevalent species were Haematopota pluvialis (23.3%), Tabanus eggeri (20.0%), and Tabanus bromius (8.0%). The former species was recorded biting humans and therefore should be considered of relevance to public health. Tabanids were more diverse and abundant in scrubland and grazing pastures [relative abundance (RA) = > 10%; species richness (S) = 8-12; Shannon-Index (H´) = 1.5 - 2.1] compared to crop landscapes (RA = < 1%; S = 0-1; H´ = 0) according to canopy traps. The tabanid population dynamics was determined to be short, with the greatest abundance and diversity concentrated in mid-late July. This study updates the checklist of this Diptera group in the Northern Spain from nine known extant species to 31 species, providing the first data on the summer peaks of activity of tabanids for this region.

New data on the subfamily Opiinae (Hymenoptera: Braconidae) from Iran.

Specimens of the Opiinae subfamily (Hymenoptera: Braconidae) were collected using Malaise traps during 2010-2011 in Northern Iran (Alborz, Guilan, Mazandaran, Qazvin and Tehran provinces). A total of 32 species belonging to 12 genera were identified, of which 11 species are new records for the fauna of Iran: Apodesmia posticatae (Fischer, 1957), Apodesmia striatula (Fischer, 1957), Biosteres (Chilotrichia) advectus Papp, 1979, Bitomus (Bitomus) multipilis Fischer, 1990, Desmiostoma parvulum (Wesmael, 1835), Opius (Misophthora) rufimixtus Fischer, 1958, Opius (Opiothorax) phytobiae Fischer, 1959, Opius (Misophthora) mischa Fischer, 1968, Opius (Opiothorax) attributus Fischer, 1962, Phaedrotoma pseudonitida (Fahringer, 1943) and Utetes curtipectus (Fischer, 1958). In addition, 21 species are new provincial records. Local and global distributions of all 32 species as well as diagnostic characters of each of the newly recorded species are provided.

Biodiversi-TEA-A quick and easy handling method for arthropod trap material in ethanol.

A quick and easy handling method for ethanol-preserved arthropods is presented, based on tea filter bags and holders. The method is especially suitable for short term storage of specimens resulting from Malaise traps, yellow pan traps and pitfall traps and can be used directly in the field, for subsequent transport and processing of specimens in the laboratory.

Establishing arthropod community composition using metabarcoding: Surprising inconsistencies between soil samples and preservative ethanol and homogenate from Malaise trap catches.

DNA metabarcoding allows the analysis of insect communities faster and more efficiently than ever before. However, metabarcoding can be conducted through several approaches, and the consistency of results across methods has rarely been studied. We compare the results obtained by DNA metabarcoding of the same communities using two different markers - COI and 16S - and three different sampling methods: (a) homogenized Malaise trap samples (homogenate), (b) preservative ethanol from the same samples, and (c) soil samples. Our results indicate that COI and 16S offer partly complementary information on Malaise trap samples, with each marker detecting a significant number of species not detected by the other. Different sampling methods offer highly divergent estimates of community composition. The community recovered from preservative ethanol of Malaise trap samples is significantly different from that recovered from homogenate. Small and weakly sclerotized insects tend to be overrepresented in ethanol while strong and large taxa are overrepresented in homogenate. For soil samples, highly degenerate COI primers pick up large amounts of nontarget DNA and only 16S provides adequate analyses of insect diversity. However, even with 16S, very little overlap in molecular operational taxonomic unit (MOTU) content was found between the trap and the soil samples. Our results demonstrate that none of the tested sampling approaches is satisfactory on its own. For instance, DNA extraction from preservative ethanol is not a valid replacement for destructive bulk extraction but a complement. In future metabarcoding studies, both should ideally be used together to achieve comprehensive representation of the target community.

A Review of Sampling and Monitoring Methods for Beneficial Arthropods in Agroecosystems.

Beneficial arthropods provide many important ecosystem services. In agroecosystems, pollination and control of crop pests provide benefits worth billions of dollars annually. Effective sampling and monitoring of these beneficial arthropods is essential for ensuring their short- and long-term viability and effectiveness. There are numerous methods available for sampling beneficial arthropods in a variety of habitats, and these methods can vary in efficiency and effectiveness. In this paper I review active and passive sampling methods for non-Apis bees and arthropod natural enemies of agricultural pests, including methods for sampling flying insects, arthropods on vegetation and in soil and litter environments, and estimation of predation and parasitism rates. Sample sizes, lethal sampling, and the potential usefulness of bycatch are also discussed.

A taxonomic study of Costa Rican Leptodrepana with the description of twenty-four new species (Hymenoptera, Braconidae, Cheloninae).

The genus Leptodrepana Shaw was described in 1983, but prior to the current study only one Neotropical species had been described from Mexico and none were named from Costa Rica. In this paper twenty-four new species are described and named from Costa Rica: L. alexisae Dadelahi & Shaw, sp. n., L. atalanta Dadelahi & Shaw, sp. n., L. conda Dadelahi & Shaw, sp. n., L. conleyae Dadelahi & Shaw, sp. n., L. demeter Dadelahi & Shaw, sp. n., L. eckerti Dadelahi & Shaw, sp. n., L. gauldilox Dadelahi & Shaw, sp. n., L. hansoni Dadelahi & Shaw, sp. n., L. kimbrellae Dadelahi & Shaw, sp. n., L. lorenae Dadelahi & Shaw, sp. n., L. munjuanae Dadelahi & Shaw, sp. n., L. ninae Dadelahi & Shaw, sp. n., L. pamelabbas Dadelahi & Shaw, sp. n., L. ronnae Dadelahi & Shaw, sp. n., L. rosanadana Dadelahi & Shaw, sp. n., L. schuttei Dadelahi & Shaw, sp. n., L. scottshawi Dadelahi, sp. n., L. shriekae Dadelahi & Shaw, sp. n., L. sohailae Dadelahi & Shaw, sp. n., L. sorayae Dadelahi & Shaw, sp. n., L. soussanae Dadelahi & Shaw, sp. n., L. stasia Dadelahi & Shaw, sp. n., L. strategeri Dadelahi & Shaw, sp. n., and L. thema Dadelahi & Shaw, sp. n. A key to Costa Rican species of Leptodrepana is provided. The flagellum of all female Leptodrepana described in this work is reduced to only 17 flagellomeres. This character state is also found in two North American species described by Shaw (1983), L. opuntiae Shaw and L. oriens Shaw. It is hypothesized that a female antenna with 17 flagellomeres is a synapomorphy for a species-group comprising all the Costa Rican Leptodrepana species as well as two of the Mexican and North American species, L. opuntiae and L. oriens.

Bee (Hymenoptera: Apoidea) Diversity and Sampling Methodology in a Midwestern USA Deciduous Forest.

Forests provide potentially important bee habitat, but little research has been done on forest bee diversity and the relative effectiveness of bee sampling methods in this environment. Bee diversity and sampling methodology were studied in an Illinois, USA upland oak-hickory forest using elevated and ground-level pan traps, malaise traps, and vane traps. 854 bees and 55 bee species were collected. Elevated pan traps collected the greatest number of bees (473), but ground-level pan traps collected greater species diversity (based on Simpson's diversity index) than did elevated pan traps. Elevated and ground-level pan traps collected the greatest bee species richness, with 43 and 39 species, respectively. An estimated sample size increase of over 18-fold would be required to approach minimum asymptotic richness using ground-level pan traps. Among pan trap colors/elevations, elevated yellow pan traps collected the greatest number of bees (266) but the lowest diversity. Malaise traps were relatively ineffective, collecting only 17 bees. Vane traps collected relatively low species richness (14 species), and Chao1 and abundance coverage estimators suggested that minimum asymptotic species richness was approached for that method. Bee species composition differed significantly between elevated pan traps, ground-level pan traps, and vane traps. Indicator species were significantly associated with each of these trap types, as well as with particular pan trap colors/elevations. These results indicate that Midwestern deciduous forests provide important bee habitat, and that the performance of common bee sampling methods varies substantially in this environment.

Review of Apanteles sensu stricto (Hymenoptera, Braconidae, Microgastrinae) from Area de Conservación Guanacaste, northwestern Costa Rica, with keys to all described species from Mesoamerica.

More than half a million specimens of wild-caught Lepidoptera caterpillars have been reared for their parasitoids, identified, and DNA barcoded over a period of 34 years (and ongoing) from Area de Conservación de Guanacaste (ACG), northwestern Costa Rica. This provides the world's best location-based dataset for studying the taxonomy and host relationships of caterpillar parasitoids. Among Hymenoptera, Microgastrinae (Braconidae) is the most diverse and commonly encountered parasitoid subfamily, with many hundreds of species delineated to date, almost all undescribed. Here, we reassess the limits of the genus Apanteles sensu stricto, describe 186 new species from 3,200+ parasitized caterpillars of hundreds of ACG Lepidoptera species, and provide keys to all 205 described Apanteles from Mesoamerica - including 19 previously described species in addition to the new species. The Mesoamerican Apanteles are assigned to 32 species-groups, all but two of which are newly defined. Taxonomic keys are presented in two formats: traditional dichotomous print versions and links to electronic interactive versions (software Lucid 3.5). Numerous illustrations, computer-generated descriptions, distributional information, wasp biology, and DNA barcodes (where available) are presented for every species. All morphological terms are detailed and linked to the Hymenoptera Anatomy Ontology website. DNA barcodes (a standard fragment of the cytochrome c oxidase I (COI) mitochondrial gene), information on wasp biology (host records, solitary/gregariousness of wasp larvae), ratios of morphological features, and wasp microecological distributions were used to help clarify boundaries between morphologically cryptic species within species-complexes. Because of the high accuracy of host identification for about 80% of the wasp species studied, it was possible to analyze host relationships at a regional level. The ACG species of Apanteles attack mainly species of Hesperiidae, Elachistidae and Crambidae (Lepidoptera). About 90% of the wasp species with known host records seem to be monophagous or oligophagous at some level, parasitizing just one host family and commonly, just one species of caterpillar. Only 15 species (9%) parasitize species in more than one family, and some of these cases are likely to be found to be species complexes. We have used several information sources and techniques (traditional taxonomy, molecular, software-based, biology, and geography) to accelerate the process of finding and describing these new species in a hyperdiverse group such as Apanteles. The following new taxonomic and nomenclatural acts are proposed. Four species previously considered to be Apanteles are transferred to other microgastrine genera: Dolichogenidea hedyleptae (Muesebeck, 1958), comb. n., Dolichogenidea politiventris (Muesebeck, 1958), comb. n., Rhygoplitis sanctivincenti (Ashmead, 1900), comb. n., and Illidops scutellaris (Muesebeck, 1921), comb. rev. One European species that is a secondary homonym to a Mesoamerican species is removed from Apanteles and transferred to another genus: Iconella albinervis (Tobias, 1964), stat. rev. The name Apanteles albinervican Shenefelt, 1972, is an invalid replacement name for Apanteles albinervis (Cameron, 1904), stat. rev., and thus the later name is reinstated as valid. The following 186 species, all in Apanteles and all authored by Fernández-Triana, are described as species nova: adelinamoralesae, adrianachavarriae, adrianaguilarae, adrianguadamuzi, aichagirardae, aidalopezae, albanjimenezi, alejandromasisi, alejandromorai, minorcarmonai, alvarougaldei, federicomatarritai, anabellecordobae, rostermoragai, anamarencoae, anamartinesae, anapiedrae, anariasae, andreacalvoae, angelsolisi, arielopezi, bernardoespinozai, bernyapui, bettymarchenae, bienvenidachavarriae, calixtomoragai, carloscastilloi, carlosguadamuzi, eliethcantillanoae, carlosrodriguezi, carlosviquezi, carloszunigai, carolinacanoae, christianzunigai, cinthiabarrantesae, ciriloumanai, cristianalemani, cynthiacorderoae, deifiliadavilae, dickyui, didiguadamuzi, diegoalpizari, diegotorresi, diniamartinezae, duniagarciae, duvalierbricenoi, edgarjimenezi, edithlopezae, eduardoramirezi, edwinapui, eldarayae, erickduartei, esthercentenoae, eugeniaphilipsae, eulogiosequeira, felipechavarriai, felixcarmonai, fernandochavarriai, flormoralesae, franciscopizarroi, franciscoramirezi, freddyquesadai, freddysalazari, gabrielagutierrezae, garygibsoni, gerardobandoi, gerardosandovali, gladysrojasae, glenriverai, gloriasihezarae, guadaluperodriguezae, guillermopereirai, juanmatai, harryramirezi, hectorsolisi, humbertolopezi, inesolisae, irenecarrilloae, isaacbermudezi, isidrochaconi, isidrovillegasi, ivonnetranae, jairomoyai, javiercontrerasi, javierobandoi, javiersihezari, jesusbrenesi, jesusugaldei, jimmychevezi, johanvargasi, jorgecortesi, jorgehernandezi, josecalvoi, josecortesi, josediazi, josejaramilloi, josemonteroi, joseperezi, joserasi, juanapui, juancarrilloi, juangazoi, juanhernandezi, juanlopezi, juanvictori, juliodiazi, juniorlopezi, keineraragoni, laurahuberae, laurenmoralesae, leninguadamuzi, leonelgarayi, lilliammenae, lisabearssae, luciariosae, luisbrizuelai, luiscanalesi, luiscantillanoi, luisgarciai, luisgaritai, luishernandezi, luislopezi, luisvargasi, manuelarayai, manuelpereirai, manuelriosi, manuelzumbadoi, marcobustosi, marcogonzalezi, marcovenicioi, mariachavarriae mariaguevarae, marialuisariasae, mariamendezae, marianopereirai, mariatorrentesae, sigifredomarini, marisolarroyoae, marisolnavarroae, marvinmendozai, mauriciogurdiani, milenagutierrezae, monicachavarriae, oscarchavesi, osvaldoespinozai, pablotranai, pabloumanai, pablovasquezi, paulaixcamparijae, luzmariaromeroae, petronariosae, randallgarciai, randallmartinezi, raulacevedoi, raulsolorsanoi, wadyobandoi, ricardocaleroi, robertmontanoi, robertoespinozai, robertovargasi, rodrigogamezi, rogerblancoi, rolandoramosi, rolandovegai, ronaldcastroi, ronaldgutierrezi, ronaldmurilloi, ronaldnavarroi, ronaldquirosi, ronaldzunigai, rosibelelizondoae, ruthfrancoae, sergiocascantei, sergioriosi, tiboshartae, vannesabrenesae, minornavarroi, victorbarrantesi, waldymedinai, wilbertharayai, williamcamposi, yeissonchavesi, yilbertalvaradoi, yolandarojasae, hazelcambroneroae, zeneidabolanosae.