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The Seybouse is the second largest river basin in Algeria, hosting an important biodiversity and providing various ecosystem services. This watershed is highly influenced by agricultural and industrial activities, which threaten its biodiversity and ecosystem integrity. The use of benthic macroinvertebrates as biological indicators has a long tradition in developed countries and integrated into all assessments of the ecological quality of river systems. However, the macroinvertebrates of many North African regions are still not well studied, including those of the Seybouse river. The aim of this study is to assess the inventory and ecological role of benthic macroinvertebrates in inland waters of the Seybouse River and determine the impact of pollution on their spatial distributions. We sampled the benthic macrofauna of Wadi Seybouse and its affluents using regular surveys in three sites, of which one was in the upper Seybouse Bouhamdane in Medjez Amar and two in the middle Seybouse. Between December 2019 and May 2020, 10 physico-chemical parameters (pH, EC, OD, water speed, NO3, Salinity, NO2, MES, turbidity, depth) were measured in order to establish a health state diagnosis of these aquatic ecosystems. The complementary biological approach by the analysis of populations of macroinvertebrates identified 7482 individuals and 40 taxa divided into five classes: Crustaceans which were the most dominant, insects with the main orders (Ephemeroptera, Diptera, Trichoptera, Heteroptera and Odonata), Molluscs, Nematodes and Annelids. The physico-chemical analyzes and the application of the organic pollution indices indicated a strong to excessive pollution for all sites, especially in Seybouse upstream Resumo O Seybouse é um rio no nordeste da Argélia, é o segundo maior rio, tem uma área de captação de cerca de 6.500 km2 que acolhe cerca de 1,5 milhões de habitantes. Importantes atividades agrícolas e industriais são desenvolvidas nesta bacia hidrográfica. O uso de macroinvertebrados bentônicos como indicadores biológicos tem uma longa tradição em países desenvolvidos e está integrado em todas as avaliações da qualidade ecológica dos sistemas fluviais. O objetivo deste estudo foi revisar o inventário e o papel ecológico dos macroinvertebrados bentônicos nas águas interiores do rio Seybouse e determinar o impacto da poluição em suas distribuições. Resultados semelhantes foram relatados para outros países e rios argelinos. Este estudo enfoca a macrofauna bentônica de Wadi Seybouse e seus afluentes. Foram prospectados 03 locais, um no alto Seybousse Bouhamdane em Medjez Amar e dois no meio Seybousse Salah Salah Salah e Oued Zimba. Entre dezembro de 2019 e maio de 2020, dez parâmetros físico-químicos (pH, CE, DO, velocidade da água, NO3, Salinidade, NO2, MES, turbidez, deth) foram medidos para estabelecer um diagnóstico do estado de saúde desses ecossistemas aquáticos. A abordagem biológica complementar pela análise de populações de macroinvertebrados identificou 7.482 indivíduos e 40 táxons divididos em cinco classes: Crustáceos que são os mais dominantes, Insetos com as ordens principais (Ephemeroptera, Diptera, Trichoptera, Heteroptera e Odonata), Moluscos, Nematóides e Anelídeos. As análises físico-químicas e a aplicação dos índices de poluição orgânica, indicaram uma poluição forte a excessiva para todos os locais especialmente Salah Salah Salah.

Planarians have the basic brain structure of an animal and, like mammals, their brain produces a variety of neurotransmitters, suggesting that they have a learning and memory function. Based on a previous study (Chicas-Mossier & Abramson, 2015), six students in seminar of the 3rd year examined the effects of shaping in the acquisition of operant conditioning by planarians. Results indicated that planarians trained by shaping acquired operant conditioning earlier than planarians not trained by shaping and that training led them to display stable operant behavior. In contrast, planarians that were not trained by shaping were slow to acquire operant behavior and they did not display stable operant behavior. The current work compared the results of this experiment to those of previous studies and it discussed the possibility that the behavioral measures used to gauge operant behavior may differ depending on the protocol and the species of planaria used. Moreover, this work discussed the feasibility of introducing operant conditioning experiments with planarians in lessons such as seminars and laboratory classes.

Predator–prey interactions shape ecosystem stability and are influenced by changes in ecosystem productivity. However, because multiple biotic and abiotic drivers shape the trophic responses of predators to productivity, we often observe patterns, but not mechanisms, by which productivity drives food web structure. One way to capture mechanisms shaping trophic responses is to quantify trophic interactions among multiple trophic groups and by using complementary metrics of trophic ecology. In this study, we combine two diet-tracing methods: diet DNA and stable isotopes, for two trophic groups (top predators and intermediate predators) in both low- and high-productivity habitats to elucidate where in the food chain trophic structure shifts in response to changes in underlying ecosystem productivity. We demonstrate that while top predators show increases in isotopic trophic position ( δ 15 N) with productivity, neither their isotopic niche size nor their DNA diet composition changes. Conversely, intermediate predators show clear turnover in DNA diet composition towards a more predatory prey base in high-productivity habitats. Taking this multi-trophic approach highlights how predator identity shapes responses in predator–prey interactions across environments with different underlying productivity, building predictive power for understanding the outcomes of ongoing anthropogenic change.

Nanopesticides (Npes) carry the potential of increased efficacy while reducing application rates, hence increasing agricultural productivity in a more sustainable way. However, given its novelty, the environmental risk assessment of these advanced materials is mostly absent. In the present study we investigated the ecotoxicity of a commercial insecticide, with reported nanofeatures, Karate Zeon®, and compared it to its active substance lambda-cyhalothrin. It is hypothesised that the use of the nanopesticide Karate Zeon® poses lower risk to enchytraeids than its active substance. The standard non-target soil invertebrate Enchytraeus crypticus was used, and exposure was done in LUFA 2.2 soil in 4 tests (endpoints: days): avoidance test [avoidance behaviour: 2 days], OECD standard reproduction test [survival, reproduction plus adults' size: 28 days] and its extension [total number organisms: 56 days], and Full Life Cycle (FLC) test [hatching and juveniles' size: 13 days; survival, reproduction and adults' size: 46 days]. Results showed that enchytraeids did not avoid Karate Zeon® nor its active substance lambda-cyhalothrin, which could be due to neurotoxicity. There was no indication of increased toxicity with prolonged exposure (46, 56d) compared to the standard (28d) for neither of the materials, being overall equally toxic in terms of hatching, survival, and reproduction. The FLCt results indicated that the juvenile stage was the most sensitive, resulting in higher toxicity for the adult animals when exposed from the cocoon stage. Although toxicity was similar between Karate Zeon and lambda-cyhalothrin, different patterns of uptake and elimination cannot be excluded. The benefits of using Karate Zeon will rely on reduced application rates. published

Across eumetazoans, the ability to perceive and respond to visual stimuli is largely mediated by opsins, a family of proteins belonging to the G protein-coupled receptor (GPCR) superclass. Lineage-specific gains and losses led to a striking diversity in the numbers, types, and spectral sensitivities conferred by visual opsin gene expression. Here, we review the diversity of visual opsins and differences in opsin gene expression from well-studied protostome, invertebrate deuterostome, and cnidarian groups. We discuss the functional significance of opsin expression differences and spectral tuning among lineages. In some cases, opsin evolution has been linked to the detection of relevant visual signals, including sexually selected color traits and host plant features. In other instances, variation in opsins has not been directly linked to functional or ecological differences. Overall, the array of opsin expression patterns and sensitivities across invertebrate lineages highlight the diversity of opsins in the eumetazoan ancestor and the labile nature of opsins over evolutionary time.

Industries such as unconventional natural gas have seen increased global expansion to meet the increasing energy needs of our increasing global population. Unconventional gas uses hydraulic fracturing that produces significant volumes of produced waters, which can be highly saline and pose a toxic threat to freshwater invertebrates if exposure via discharges, spills, leaks, or runoff were to occur. The primary aim of the present review was to determine the sodium (Na

Biological communities in freshwater streams are often impaired by multiple stressors (e.g., flow or water quality) originating from anthropogenic activities such as urbanization, agriculture, or energy extraction. Restoration efforts in the Chesapeake Bay watershed, USA seek to improve biological conditions in 10% of freshwater tributaries and to protect the biological integrity of existing healthy watersheds. To achieve these goals, resource managers need to better understand which stressors are most likely driving biological impairment. Our study addressed this knowledge gap through two approaches: 1) reviewing and synthesizing published multi-stressor studies, and 2) examining 303(d) listed impairments linked to biological impairment as identified by jurisdiction regulatory agencies (the states within the watershed and the District of Columbia). Results identified geomorphology (i.e., physical habitat), salinity, and toxic contaminants as important for explaining variability in benthic community metrics in the literature review. Geomorphology (i.e., physical habitat and sediment), salinity, and nutrients were the most reported stressors in the jurisdictional impairment analysis. Salinity is likely a major stressor in urban and mining settings, whereas geomorphology was commonly reported in agricultural settings. Toxic contaminants, such as pesticides, were rarely measured; more research is needed to quantify the extent of their effects in the region. Flow alteration was also highlighted as an important urban stressor in the literature review but was rarely measured in the literature or reported by jurisdictions as a cause of impairment. These results can be used to prioritize stressor monitoring by managers, and to improve stressor identification methods for identifying causes of biological impairment.

Amphibians are declining worldwide due to a combination of stressors such as climate change, invasive species, habitat loss, pollution and emergent diseases. Although their losses are likely to have important ecological consequences on the structure and functioning of freshwater ecosystems, this issue has been scarcely explored. We conducted an experiment in three montane streams-where primary production is the main source of energy and carbon-to assess the effects of amphibian disappearance (i.e. presence or absence of the common midwife toad Alytes obstetricans, a common species found in pools of these streams) on several aspects of ecosystem functioning and structure: periphyton biomass and chlorophyll a concentration, algal assemblage structure, and growth of macroinvertebrate grazers. We compared four types of experimental enclosures: (i) without macroinvertebrates or amphibians; (ii) with larvae of the caddisfly Allogamus laureatus; (iii) with A. obstetricans tadpoles; and (iv) with both A. laureatus larvae and A. obstetricans tadpoles. The absence of tadpoles increased periphyton biomass, but did not cause differences on inorganic sediment accrual. The algal assemblage had a higher diversity in the absence of tadpoles, and their characteristic taxa differed from the assemblages in presence of tadpoles. A. laureatus presented higher mass in presence of tadpoles; however, tadpole length was not affected by presence of macroinvertebrates. Our results suggest that presence of tadpoles is a driver of periphyton accrual and assemblage structure, acting as top-down control and with key potential consequences on the functioning of montane stream ecosystems.La población de anfibios está reduciéndose globalmente debido a una combinación de factores como el cambio climático, las especies invasoras, la pérdida de hábitat, la contaminación y las enfermedades emergentes. Aunque su desaparición probablemente causará consecuencias ecológicas importantes en la estructura y el funcionamiento de los ecosistemas de agua dulce, es un aspecto que ha sido poco explorado. Se realizó un experimento en tres arroyos de montaña, donde la producción primaria es la principal fuente de energía y carbono, para determiner los efectos de la desaparición de los anfibios (presencia o ausencia del sapo partero común Alytes obstetricans, una especie común en pozas de estos arroyos) en varios aspectos del funcionamiento y la estructure del ecosistema: la biomasa de perifiton y la concentración de clorofila, la estructura de la comunidad algal y el crecimiento de los macroinvertebrados raspadores. Comparamos cuatro tipos de recintos: (i) sin macroinvertebrados ni anfibios; (ii) con larvas del tricóptero Allogamus laureatus; (iii) con renacuajos de A. obstetricans; y (iv) con tanto larvas de A. laureatus como renacuajos de A. obstetricans. La ausencia de renacuajos aumentaba la biomasa de perifiton, aunque no causaba diferencias en la acumulación de sedimento inorgánico. La comunidad de algas presentaba una mayor diversidad en ausencia de renacuajos, y sus taxones característicos eran distintos de los de las comunidades con presencia de renacuajos. A. laureatus tenía una mayor masa en presencia de renacuajos, pero la longitud de los renacuajos no se veía afectada por la presencia de macroinvertebrados. Nuestros resultados sugieren que la presencia de renacuajos controla la acumulación de perifiton y la estructura de las comunidades, ejerciendo un control de arriba hacia abajo, con consecuencias clave en el funcionamiento de los ecosistemas de arroyos de montaña.

Organisms in coastal waters experience naturally high oxygen variability and steep oxygen gradients with depth, in addition to ocean deoxygenation. They often undergo diel vertical migration involving a change in irradiance that initiates a visual behavior. Retinal function has been shown to be highly sensitive to oxygen loss; here we assess whether visual behavior (photobehavior) in paralarvae of the squid

Predictions for climate change-to lesser and greater extents-reveal a common scenario in which marine waters are characterized by a deadly trio of stressors: higher temperatures, lower oxygen levels, and acidification. Ectothermic taxa that inhabit coastal waters, such as shellfish, are vulnerable to rapid and prolonged environmental disturbances, such as heatwaves, pollution-induced eutrophication, and dysoxia. Oxygen transport capacity of the hemolymph (blood equivalent) is considered the proximal driver of thermotolerance and respiration in many invertebrates. Moreover, maintaining homeostasis under environmental duress is inextricably linked to the activities of the hemolymph-based oxygen transport or binding proteins. Several protein groups fulfill this role in marine invertebrates: copper-based extracellular hemocyanins, iron-based intracellular hemoglobins and hemerythrins, and giant extracellular hemoglobins. In this brief text, we revisit the distribution and multifunctional properties of oxygen transport proteins, notably hemocyanins, in the context of climate change, and the consequent physiological reprogramming of marine invertebrates.

Marine organisms often produce a variety of metabolites with unique structures and diverse biological activities that enable them to survive and struggle in the extremely challenging environment. During the last two decades, our group devoted great effort to the discovery of pharmaceutically interesting lead compounds from South China Sea marine plants and invertebrates. We discovered numerous marine secondary metabolites spanning a wide range of structural classes, various biosynthetic origins and various aspects of biological activities. In a series of reviews, we have summarized the bioactive natural products isolated from Chinese marine flora and fauna found during 2000-2012. The present review provides an updated summary covering our latest research progress and development in the last decade (2012-2022) highlighting the discovery of over 400 novel marine secondary metabolites with promising bioactivities from South China Sea marine organisms.

Global warming is affecting the Antarctic continent in complex ways. Because Antarctic organisms are specialized to living in the cold, they are vulnerable to increasing temperatures, although quantitative analyses of this issue are currently lacking. Here we compiled a total of 184 estimates of heat tolerance belonging to 39 marine species and quantified how survival is affected concomitantly by the intensity and duration of thermal stress. Species exhibit thermal limits displaced toward colder temperatures, with contrasting strategies between arthropods and fish that exhibit low tolerance to acute heat challenges, and brachiopods, echinoderms, and molluscs that tend to be more sensitive to chronic exposure. These differences might be associated with mobility. A dynamic mortality model suggests that Antarctic organisms already encounter temperatures that might be physiologically stressful and indicate that these ecological communities are indeed vulnerable to ongoing rising temperatures.El calentamiento global está afectando al continente antártico de formas complejas. Dado que los organismos antárticos están especializados a vivir en el frío, son vulnerables al aumento de las temperaturas, aunque en la actualidad hay carencia de análisis cuantitativos al respecto. Aquí recopilamos un total de 184 estimaciones de tolerancia al calor pertenecientes a 39 especies marinas, y cuantificamos cómo la supervivencia de estos organismos se ve afectada concomitantemente por la intensidad y la duración de un estrés térmico. Efectivamente las especies antárticas muestran límites térmicos desplazados hacia temperaturas más frías, con estrategias contrastadas entre los artrópodos y los peces que muestran una baja tolerancia a los desafíos térmicos agudos, y los braquiópodos, equinodermos y moluscos que tienden a ser más sensibles a la exposición crónica. Estas diferencias podrían estar asociadas con la movilidad. Un modelo dinámico de mortalidad sugiere que los organismos antárticos ya se enfrentan a temperaturas que podrían ser fisiológicamente estresantes e indican que estas comunidades ecológicas son realmente vulnerables al aumento continuo de las temperaturas.

Heatwave frequency and intensity will increase as climate change progresses. Intertidal sessile invertebrates, which often form thermally benign microhabitats for associated species, are vulnerable to thermal stress because they have minimal ability to behaviourally thermoregulate. Understanding what factors influence the mortality of biogenic species and how heatwaves might impact their ability to provide habitat is critical. Here, we characterize the community associated with the thatched barnacle, Semibalanus cariosus (Pallass, 1788), in British Columbia (BC), Canada. Then, we investigate what site-level and plot-level environmental factors explained variations in barnacle mortality resulting from an unprecedented regional heatwave in BC, Canada. Furthermore, we used a manipulative shading experiment deployed prior to the heatwave to examine the effect of thermal stress on barnacle survival and recruitment and the barnacle-associated community. We identified 50 taxa inhabiting S. cariosus beds, with variations in community composition between sites. Site-scale variables and algal canopy cover did not predict S. cariosus mortality, but patch-scale variation in substratum orientation did, with more direct solar irradiance corresponding with higher barnacle mortality. The shading experiment demonstrated that S. cariosus survival, barnacle recruitment, and invertebrate community diversity were higher under shades where substratum temperatures were lower. Associated community composition also differed between shaded and non-shaded plots, suggesting S. cariosus was not able to fully buffer acute thermal stress for its associated community. While habitat provisioning by intertidal foundation species is an important source of biodiversity, these species alone may not be enough to prevent substantial community shifts following extreme heatwaves. As heatwaves become more frequent and severe, they may further reduce diversity via the loss of biogenic habitat, and spatial variation in these impacts may be substantial.

Our previous studies showed that invertebrate animal serine racemase (SerR) and aspartate racemase (AspR) evolved from a common ancestral gene and are widely distributed. However, the overall molecular evolutionary background of these genes has remained unclear. In the present study, we have cloned, expressed and characterized five SerR and three AspR genes from six invertebrate species. The coexistence of SerR and AspR paralogs has been observed in some species, and the presence of both SerR and AspR is here confirmed in the flatworm Macrostomum lignano, the feather star Anneissia japonica, the ark shell Anadara broughtonii and the sea hare Aplysia californica. Comparison of the gene structures revealed the evolution of SerR and AspR. The ancestral species of metazoans probably had a single SerR gene, and the first gene duplication in the common ancestor species of the eumetazoans occurred after the divergence of porifera and eumetazoans, yielding two SerR genes. Most eumetazoans lost one of the two SerR genes, while the echinoderm A. japonica retained both genes. Furthermore, it is clear that invertebrate AspR genes arose through parallel evolution by duplication of the SerR gene followed by substitution of amino acid residues necessary for substrate recognition in multiple lineages.

In light of ongoing climate change, it is increasingly important to know how nutritional requirements of ectotherms are affected by changing temperatures. Here, we analyse the wide thermal response of phosphorus (P) requirements via elemental gross growth efficiencies of Carbon (C) and P, and the Threshold Elemental Ratios in different aquatic invertebrate ectotherms: the freshwater model species Daphnia magna, the marine copepod Acartia tonsa, the marine heterotrophic dinoflagellate Oxyrrhis marina, and larvae of two populations of the marine crab Carcinus maenas. We show that they all share a non-linear cubic thermal response of nutrient requirements. Phosphorus requirements decrease from low to intermediate temperatures, increase at higher temperatures and decrease again when temperature is excessive. This common thermal response of nutrient requirements is of great importance if we aim to understand or even predict how ectotherm communities will react to global warming and nutrient-driven eutrophication.

Invertebrate gleaning is a small-scale fishery that commonly occurs in the intertidal zone across the tropical Indo-Pacific. In this study, we investigated and analyzed several components of this fishery on the island of Unguja, Zanzibar by employing the social-ecological systems framework from Ostrom 2009. In doing so, we conducted ecological surveys, catch assessments, interviews with gleaners, household surveys, focus group interviews and analyzed the governance structure. This social-ecological systems analysis showed that gleaning is important for food security, local culture and livelihood. Yet, the multiple approaches in our study revealed that the local intertidal zone is degrading and that the gleaned catch is changing. Local narratives indicate that economically important bivalves (Modiolus spp.) and gastropods (Strombus spp.) are in decline, which was paralleled with low abundances of both genera within the ecological survey of the intertidal and catch landing assessment. We recommend that invertebrate gleaning, a fishery mainly comprised of women should be included in fisheries management.

Arbuscular mycorrhizal (AM) fungi and soil invertebrates represent a large proportion of total soil biomass and biodiversity and are vital for plant performance, soil structure, and biogeochemical cycling. However, the role of soil invertebrates in AM fungi development remains elusive. In this opinion article, we summarize the ecological importance of AM fungi and soil invertebrates in the plant-soil continuum and highlight the effects of soil invertebrates on AM fungal hyphae development and functioning. In a context of global change, we envision that better mechanistic understanding of the complex feedback via chemical signaling pathways across the interactions between soil invertebrates and AM fungi is critical to predict their ecological consequences and will open new avenues for promoting ecosystem resilience and sustainability.

First described in 2004 off California, Osedax worms are now known from many of the world's oceans, ranging from 10 to over 4000 m in depth. Currently, little is known about species ranges, since most descriptions are from single localities. In this study, we used new sampling in the north-eastern Pacific and available GenBank data from off Japan and Brazil to report expanded ranges for five species: Osedax frankpressi, O. knutei, O. packardorum, O. roseus and O. talkovici. We also provided additional DNA sequences from previously reported localities for two species: Osedax priapus and O. randyi. To assess the distribution of each species, we used cytochrome c oxidase subunit I (COI) sequences to generate haplotype networks and assess connectivity amongst localities where sampling permitted. Osedax frankpressi, O. packardorum, O. priapus, O. roseus and O. talkovici all had one or more dominant COI haplotypes shared by individuals at multiple localities, suggesting high connectivity throughout some or all of their ranges. Low ΦST values amongst populations for O. packardorum, O. roseus and O. talkovici confirmed high levels of gene flow throughout their known ranges. High ΦST values for O. frankpressi between the eastern Pacific and the Brazilian Atlantic showed little gene flow, reflected by the haplotype network, which had distinct Pacific and Atlantic haplotype clusters. This study greatly expands the ranges and provides insights into the phylogeography for these nine species.

Delayed toxicity is a phenomenon observed for aquatic invertebrates exposed to nicotinic acetylcholine receptor (nAChR) agonists, such as neonicotinoids. Furthermore, recent studies have described an incomplete elimination of neonicotinoids by exposed amphipods. However, a mechanistic link between receptor binding and toxicokinetic modeling has not been demonstrated yet. The elimination of the neonicotinoid thiacloprid in the freshwater amphipod Gammarus pulex was studied in several toxicokinetic exposure experiments, complemented with in vitro and in vivo receptor-binding assays. Based on the results, a two-compartment model was developed to predict the uptake and elimination kinetics of thiacloprid in G. pulex. An incomplete elimination of thiacloprid, independent of elimination phase duration, exposure concentrations, and pulses, was observed. Additionally, the receptor-binding assays indicated irreversible binding of thiacloprid to the nAChRs. Accordingly, a toxicokinetic-receptor model consisting of a structural and a membrane protein (including nAChRs) compartment was developed. The model successfully predicted internal thiacloprid concentrations across various experiments. Our results help in understanding the delayed toxic and receptor-mediated effects toward arthropods caused by neonicotinoids. Furthermore, the results suggest that more awareness toward long-term toxic effects of irreversible receptor binding is needed in a regulatory context. The developed model supports the future toxicokinetic assessment of receptor-binding contaminants., Environmental Science & Technology, 57 (24), ISSN:0013-936X, ISSN:1520-5851

Soil invertebrate communities represent a significant fraction of global biodiversity and play crucial roles in ecosystems. A number of human activities threaten soil communities, in particular intensive agricultural practices such as pesticide use. However, there is currently no quantitative synthesis of the impacts of pesticides on soil fauna communities. Here, using a meta-analysis of 54 studies and 294 observations, we quantify pesticide effects on the abundance, biomass, richness and diversity of natural soil fauna communities across a wide range of environmental contexts. We also identify scenarios with the most detrimental effects on soil fauna communities by analysing the effects of different pesticides (herbicides, fungicides, insecticides, broad-spectrum substances and multiple substances), different application rates and temporal extents (short- or long-term), as well as the response of different functional groups of soil animals (body size categories, presence of exoskeleton). Pesticides overall decreased the abundance and diversity of soil fauna communities across studies (Grand mean effect size (Hedge's g) = −0.30 +/− 0.16) and had stronger effects on soil fauna diversity than abundance. The most detrimental scenarios involved multiple substances, broad-spectrum substances and insecticides, which significantly decreased soil fauna diversity even at recommended rates. We found no evidence that pesticide effects dampen over time, as short-term and long-term studies exhibited similar mean effect sizes. Policy implications: Our study highlights that pesticide use has significant detrimental non-target effects on soil biodiversity, eroding a substantial part of global biodiversity and threatening ecosystem health. This provides crucial evidence supporting recent policies, such as the European Green Deal, that aim to reduce pesticide use in agriculture to conserve biodiversity. The detrimental effects of multiple substances revealed here are particularly concerning because realistic pesticide use often combines several substances targeting different pests and diseases over the crop season. We suggest that future guidelines for pesticide registration, restrictions and banning should rely on data able to fully capture the long-term consequences of multiple substances for multiple non-target species in realistic conditions.

Soil invertebrate communities represent a significant fraction of global biodiversity and play crucial roles in ecosystems. A number of human activities threaten soil communities, in particular intensive agricultural practices such as pesticide use. However, there is currently no quantitative synthesis of the impacts of pesticides on soil fauna communities. Here, using a meta-analysis of 54 studies and 294 observations, we quantify pesticide effects on the abundance, biomass, richness and diversity of natural soil fauna communities across a wide range of environmental contexts. We also identify scenarios with the most detrimental effects on soil fauna communities by analysing the effects of different pesticides (herbicides, fungicides, insecticides, broad-spectrum substances and multiple substances), different application rates and temporal extents (short- or long-term), as well as the response of different functional groups of soil animals (body size categories, presence of exoskeleton). Pesticides overall decreased the abundance and diversity of soil fauna communities across studies (Grand mean effect size (Hedge's g) = −0.30 +/− 0.16) and had stronger effects on soil fauna diversity than abundance. The most detrimental scenarios involved multiple substances, broad-spectrum substances and insecticides, which significantly decreased soil fauna diversity even at recommended rates. We found no evidence that pesticide effects dampen over time, as short-term and long-term studies exhibited similar mean effect sizes. Policy implications: Our study highlights that pesticide use has significant detrimental non-target effects on soil biodiversity, eroding a substantial part of global biodiversity and threatening ecosystem health. This provides crucial evidence supporting recent policies, such as the European Green Deal, that aim to reduce pesticide use in agriculture to conserve biodiversity. The detrimental effects of multiple substances revealed here are particularly concerning because realistic pesticide use often combines several substances targeting different pests and diseases over the crop season. We suggest that future guidelines for pesticide registration, restrictions and banning should rely on data able to fully capture the long-term consequences of multiple substances for multiple non-target species in realistic conditions.

The study was carried out in the municipalities of Uberlândia and Monte Alegre (state of Minas Gerais) in southeastern Brazil. The climate has two well-defined seasons: a dry winter (May to September) and a rainy summer (October to April). Mean annual temperature and precipitation are 22ºC and 1,600 mm, respectively. The region consists of a mosaic of different land uses, including anthropogenic covers and remnants of different native vegetation types, which range from open grassland to closed canopy forest. We selected 40 study sites in five dominant land uses (i.e., 8 replicate sites per land use; Fig. 1): (i) savanna: native vegetation known as “cerrado sensu stricto”, dominated by grasses, but with scattered trees and shrubs (3-8 m tall) that create a canopy cover of ~ 30%; (ii) forest: native seasonal semi-deciduous forest growing on relatively fertile soils, with canopy heights of 10-20 m, and a diverse flora; (iii) eucalypt: tree plantations of Eucalyptus spp. that are clearcut every 7-10 years and have an understory vegetation 2-4 m tall (the plantations we sampled were 6-8 years old and had a canopy height of ~20 m); (iv) pasture: areas planted with introduced grasses for livestock production (2-40 cows/ha), with scattered trees (~5 trees/ha); parasiticides, which are known to have negative effects on dung beetles, are applied 3-14 times per year; and (v) soybean: plantations used for mechanized production of soy, but without tillage (at the time of this study, soy plants were one month old and approximately 15 cm high). Study sites were separated from each other by at least 1 km, and sites with different land uses were interspersed in the whole study region. Beetles were sampled once in each of the 40 sites, between November and December 2017, using 8 pitfall traps per site. In each site, we delimited a 100 x 100 m plot. The borders of each plot were ≥ 75 m away from any other land use type. Traps were buried level with the soil surface at the corners and midpoints of the plot’s sides. Traps consisted of a plastic container (19 cm diameter, 11 cm height) which was filled to two thirds of its capacity with water containing a pinch of salt and odourless detergent. Inside the container, a plastic cup (4 cm diam, 4 cm high) was suspended, which contained 40 g of a mixture of pig dung and human faeces (4:1 proportion). A 20 cm diameter plastic cover was placed ~20 cm above each trap to protect it from rain and direct sun. After 48 h we collected all beetles. Dung beetles were counted and identified to species or morphospecies. We dried 30 individuals per species (or fewer, when 30 were not available) at 40 ºC until reaching constant weight (approx. 72 h). Dry weights were measured on a precision scale (0.001 mg) to estimate the mean body mass of each species. We classified species into two size categories: small beetles (< 100 mg) and large beetles (≥ 100 mg). We also classified species according to their dung-relocation behaviour into rollers, tunnellers and dwellers, and the expert opinion of one of us (FVdM). Beetle voucher specimens were deposited at the collections of the Federal University of Uberlândia (UFU) and the Federal University of Mato Grosso (UFMT). Field work was carried out under permit number 16823-2 issued by the ‘Chico Mendes Institute for Biodiversity Conservation (ICMBIO)’. According to Brazilian regulations, ethical approval for this study was not required. To obtain a single representative sample of the dung beetle assemblage at each site, we pooled (summed) capture data from the eight traps. In each site, we measured five assemblage attributes: species density (number of species captured per plot), abundance of large beetles, abundance of small beetles, functional richness (FRic), and functional dispersion (FDq). We also calculated three metrics that are often used in dung beetle studies (total abundance, total biomass, and assemblage composition), but we did not include them in the analyses because they were highly correlated with at least one of the five variables previously described (Spearman correlation coefficient ≥ 0.8 and P < 0.05). The two functional metrics that we chose (FRic and FDq) describe complementary aspects of functional diversity.FRic is based on the total range of traits and represents the amount of the functional space occupied by all the species in an assemblage. On the other hand, FDq is the mean dissimilarity (based on functional traits) of all pairs of species in an assemblage and is therefore a measure of functional dispersion. To calculate the functional diversity metrics, we used body mass (continuous variable) and dung-relocation behaviour (categorical). We considered these two functional traits because they are related to beetles’ dispersal abilities, their responses to habitat modification, and their ecosystem functions (Nichols et al., 2008). We used the ‘FD’ package in R 4.0.5to estimate FRic and FDq. Measures of landscape structure were based on a map of the study region obtained from a Landsat time series derived from MapBiomas (Collection 5.0) using Google Earth Enginefor the period of dung beetle sampling. We measured landscape variables using a site-landscape approach: around the centre of each plot used for beetle sampling, we delimited eight circular concentric landscapes with radii varying between 300 and 1000 m, at 100 m increments . We used landscapes with different sizes to assess the scale of effect for each response-predictor combination Landscapes did not overlap, except in one case (spatial overlap of 45% between two landscapes at the 1000 m scale). MapBiomas recognizes 22 land uses for Brazil, of which only 12 appeared in our landscapes: forest, savanna, grassland, tree plantation, pasture, soybean, perennial crop, sugar cane, other temporary crop, urban infrastructure, river/lake, and other unvegetated areas. MapBiomas distinguishes two types of native open vegetation: savanna and grassland. Savannas have well-defined tree and shrub strata, whereas in grasslands the herbaceous stratum predominates. However, for our study we pooled these two categories into one category, which we called savanna, because they share a common dung beetle assemblage. Thus, for the purpose of our study we recognized 11 land use types. In each circular landscape, we quantified four landscape variables that can affect dung beetle assemblages: percentage of savanna cover, percentage of forest cover, landscape compositional heterogeneity, and matrix harshness. We estimated compositional heterogeneity by calculating the exponential of Shannon entropy (Hill number of order 1), which is interpreted as the effective number of common (typical) land uses in the landscape. We defined the matrix as the area in a landscape not covered by native vegetation, and we used the percentage of the matrix covered by treeless monoculture crops (i.e., MapBiomas categories: soybean, sugar cane, perennial crop, and other temporary crop) as a proxy for matrix harshness. The percentages of areas occupied by the different land uses were measured using QGIS.

Seeds are commonly viewed as the mainstay of the diet of desert rodents. We describe the diet of a common Australian desert rodent, the sandy inland mouse Pseudomys hermannsburgensis, using direct observations of free-living animals and analysis of the stomach contents of preserved specimens. Direct observations showed that animals forage mostly on the ground surface and eat seeds from a wide range of plant species, as well as invertebrates and occasional green plant material. Stomach content analysis revealed no differences in the presence or absence of these three major food groups between seasons or the sexes. However, invertebrates were more prominent in the diet of mice during prolonged, dry, population ‘bust’ periods compared with post-rain population ‘boom’ periods, with this dietary shift probably reflecting a scarcity of seeds during the busts. The results confirm that seed is an important component of the diet of P. hermannsburgensis, with 92% of stomachs containing seed. The results also support the classification of the species as omnivorous rather than granivorous, with 70% of stomachs containing invertebrates and over half the specimens analysed containing both seeds and invertebrates. We suggest that dietary flexibility is important for rodent persistence in Australia’s climatically unpredictable arid regions.

The Ebre Delta (NW Mediterranean), which is considered a highly vulnerable ecosystem, is one of the most important European wetlands and belongs to the Natura 2000 network. The present study aims to characterize the benthic megainvertebrate communities inhabiting the Ebre Delta soft-bottom infralittoral to acquire faunistic and biological knowledge for two periods of time, 23 years apart. Experimental trawls were conducted during the two periods (1992–1993 and 2016–2017) in three depth strata, between 5 and 25 m. A total of 139 and 170 taxa were collected at each period, respectively. Our results showed that community species composition and structure varied between periods and among depth strata. Overall, a large decrease in density and biomass was detected for most species in all three depth strata examined (0–5, 15–20, and 20–25 m) in 2016–2017, especially in the shallowest stratum. Species richness was higher in 2016–2017 than in 1992–1993, and the lowest values were found at the shallowest stratum in both periods. The significant biomass losses herein reported highlight the need to increase, in time and effort, the monitoring of large marine invertebrates in coastal areas, where many taxa provide important ecosystem functions and services., This study is part of the research projects “Análisis del impacto de la pesca con ’rastell’ sobre las poblaciones de organismos marinos” and “Evaluación y seguimiento del Plan de Gestión de Dragas para Embarcación”, ref. AG-2016-233, funded by the Department d’Agricultura, Ramaderia i Pesca (Generalitat de Catalunya, Spain).

Small animals (epifauna) are ubiquitous in marine systems. Epifauna have high secondary production and provide trophic linkages between primary producers and higher-order consumers, like fish. Despite their importance, little is known about how these animals respond to warming or how their communities vary across spatiotemporal gradients. Here we use mimics of turf seaweed and invasive kelp holdfast to test, in a 5-factorial field experiment, whether intertidal epifauna are facilitated by different habitat structures, temperature conditions, and along cooccurring spatiotemporal gradients. We found that facilitation of epifauna by intertidal turf seaweed peaked in summer, at low elevation, in older habitats and at a less wave-exposed site. However, epifauna were not affected by the presence of a secondary structure like kelp holdfast mimics or small temperature increases from passive solar heating of black and white mimics. There were many significant two-way, but few higher order interactions, showing stronger facilitation under specific environmental conditions, like at low elevation in summer, or low elevation in old habitats. These results highlight that turf-associated epifauna are controlled by vertical elevation, season, hydrodynamics, and habitat age, and appear to be resilient to small temperature increases. Findings are important to better understand linkages between primary producers and higher order consumers and system-wide productivity, and because fast growing turf, facilitated by global warming and eutrophication, are increasingly outcompeting slower growing large perennial canopy forming seaweeds, like kelp and rockweeds.

The environmental impacts of plastic pollution have recently attracted universal attention, especially in the aquatic environment. However, research has mostly been focused on marine ecosystems, even though freshwater ecosystems are equally if not more polluted by plastics. In addition, the mechanism and extent to which plastic pollution affects aquatic biota and the rates of transfer to organisms through food webs eventually reaching humans are poorly understood, especially considering leaching hazardous chemicals. Several studies have demonstrated extreme toxicity in freshwater organisms such Daphnia. When such keystone species are affected by ambient pollution, entire food webs are destabilized and biodiversity is threatened. The unremitting increase in plastic contaminants in freshwater environments would cause impairments in ecosystem functions and structure, leading to various kinds of negative ecological consequences. As various studies have reported the effects on daphnids, a consolidation of this literature is critical to discuss the limitations and knowledge gaps and to evaluate the risk posed to the aquatic environment. This review was undertaken due to the evident need to evaluate this threat. The aims were to provide a meaningful overview of the literature relevant to the potential impact of plastic pollution and associated contaminants on freshwater daphnids as primary consumers. A critical evaluation of research gaps and perspectives is conducted to provide a comprehensive risk assessment of microplastic as a hazard to aquatic environments. We outlined the challenges and limitations to microplastic research in hampering better-focused investigations that could support the development of new plastic materials and/or establishment of new regulations.

Large-scale desalination is used increasingly to address growing freshwater demands and climate uncertainty. Discharge of hypersaline brine from desalination operations has the potential to impact marine ecosystems. Here, we used a 7-year Multiple-Before-After-Control-Impact experiment to test the hypothesis that hypersaline discharge from reverse osmosis desalination alters temperate reef communities. Using replicated, video-based, timed searches at eight sites, we sampled fish and invertebrate assemblages before, during, and after the discharge of hypersaline brine. We found that the composition of fish assemblages was significantly altered out to 55 m while the composition of invertebrate assemblages was altered out to 125 m from the outlet during hypersaline discharge. Fish richness and functional diversity increased around the outlet, while the invertebrate assemblages were no less diverse than those on reference reefs. Differences in faunal assemblages between outlet and reference sites during discharging included changes in the frequency of occurrence of both common and rare reef biota. Overall, we found the influence of hypersaline discharge on temperate reef biota to be spatially localized, with the reefs around the outlet continuing to support rich and diverse faunal communities. In some cases, therefore, the marine environmental consequences of large-scale, well-designed, desalination operations may be appropriately balanced against the positive benefits of improved water security.

Anthropogenic global warming is redistributing marine life and may threaten tropical benthic invertebrates with several potential extinction mechanisms. The net impact of climate change on geographical extinction risk nevertheless remains uncertain. Evidence of widespread climate‐driven extinctions and of potentially unidentified mechanisms exists in the fossil record. We quantify organism extinction risk across thermal habitats, estimated by paleoclimate reconstructions, over the past 300 million years. Extinction patterns at seven known events of rapid global warming (hyperthermals) differ significantly from typical patterns, resembling those driven by global geometry under simulated global warming. As isotherms move poleward with warming, the interaction between the geometry of the globe and the temperature‐latitude relationship causes an uneven loss of thermal habitat and a bimodal latitudinal distribution of extinctions. Genera with thermal optima warmer than ~21°C show raised extinction odds, while extinction odds continually increase for genera with optima below ~11°C. Genera preferring intermediate temperatures generally have no additional extinction risk during hyperthermals, except under extreme conditions as the end‐Permian mass extinction. Widespread present‐day climate‐driven range shifts indicate that occupancy loss is already underway. Given the most‐likely projections of modern warming, our model, validated by seven past hyperthermal events, indicates that sustained warming has the potential to annihilate cold‐water habitat and its endemic species completely within centuries.

Coral reef soundscapes are increasingly studied for their ecological uses by invertebrates and fishes, for monitoring habitat quality, and to investigate effects of anthropogenic noise pollution. Few examinations of aquatic soundscapes have reported particle motion levels and variability, despite their relevance to invertebrates and fishes. In this study, ambient particle acceleration was quantified from orthogonal hydrophone arrays over several months at four coral reef sites, which varied in benthic habitat and fish communities. Time-averaged particle acceleration magnitudes were similar across axes, within 3 dB. Temporal trends of particle acceleration corresponded with those of sound pressure, and the strength of diel trends in both metrics significantly correlated with percent coral cover. Higher magnitude particle accelerations diverged further from pressure values, potentially representing sounds recorded in the near field. Particle acceleration levels were also reported for boat and example fish sounds. Comparisons with particle acceleration derived audiograms suggest the greatest capacity of invertebrates and fishes to detect soundscape components below 100 Hz, and poorer detectability of soundscapes by invertebrates compared to fishes. Based on these results, research foci are discussed for which reporting of particle motion is essential, versus those for which sound pressure may suffice.

Invertebrates are a significant source of antimicrobial peptides because they lack an adaptive immune system and must rely on their innate immunity to survive in a pathogen-infested environment. Various antimicrobial peptides that represent major components of invertebrate innate immunity have been described in a number of investigations over the last few decades. In freshwater invertebrates, antimicrobial peptides have been identified in arthropods, annelids, molluscs, crustaceans, and cnidarians. Freshwater invertebrate species contain antimicrobial peptides from the families astacidin, macin, defensin, and crustin, as well as other antimicrobial peptides that do not belong to these families. They show broad spectrum activities greatly directed against bacteria and to a less extent against fungi and viruses. This review focuses on antimicrobial peptides found in freshwater invertebrates, highlighting their features, structure-activity connections, antimicrobial processes, and possible applications in the food industry, animal husbandry, aquaculture, and medicine. The methods for their synthesis, purification, and characterization, as well as the obstacles and strategies for their development and application, are also discussed.

Chemicals used in sea lice management strategies in salmonid aquaculture include the avermectin class of compounds that can accumulate and persist in the sediments underneath salmon farms and directly impact nontarget benthic fauna. The effects of sediment organic carbon content and chemical residence time (CRT) on the lethal and sublethal toxicity of emamectin benzoate (EB; formulation: Slice®) and ivermectin (purified) and a combination of both were examined in two benthic invertebrates, the amphipod Eohaustorius estuarius and the polychaete Neanthes virens. In both species, increased sediment organic carbon content significantly reduced lethal toxicity, a modulation that was more pronounced for ivermectin and combination exposures. At a CRT of 4 months, lethal toxicity was reduced in E. estuarius but was unaffected in N. virens. Sublethal toxicity in N. virens (burrowing behavior) was modulated by sediment organic carbon and CRT in a similar manner to the trend in lethal toxicity. Inconsistencies in behavior (phototaxis) in E. estuarius made conclusions regarding toxicity modification by sediment organic carbon or CRT inconclusive. Our results indicate that environmental factors including sediment organic carbon content and the time compounds reside in sediments are important modifiers of chemotherapeutant toxicity in nontarget benthic species and should be considered when regulatory decisions regarding their use are made. Environ Toxicol Chem 2022;41:1918-1936. © 2022 SETAC.

Abstract Concentrations of major ions in coal mine discharge waters and unconventional hydrocarbon produced waters derived from coal bed methane (CBM) production, are potentially harmful to freshwater ecosystems. Bicarbonate is a major constituent of produced waters from CBM and coal mining. However, little is known about the relative toxicity of differing ionic proportions, especially bicarbonate, found in these CBM waters. As all freshwater invertebrates tested are more acutely sensitive to sodium bicarbonate (NaHCO3) than sodium chloride (NaCl) or synthetic sea water, we tested the hypotheses that toxicity of CBM waters are driven by bicarbonate concentration, and waters containing a higher proportion of bicarbonate are more toxic to freshwater invertebrates than those with less bicarbonate. We compared the acute (96 h) lethal toxicity to six freshwater invertebrate species of NaHCO3 and two synthetic CBM waters, with ionic proportions representative of water from CBM wells across New South Wales (NSW) and Queensland (Qld), in Australia. The ranking of LC50 values expressed as total salinity was consistent with the hypotheses. However, when toxicity was expressed as bicarbonate concentration, the hypothesis that the toxicity of coal bed waters would be explained by bicarbonate concentration was not well supported, and other ionic components were either ameliorating or exacerbating the NaHCO3 toxicity. Our findings showed NaHCO3 was more toxic than NaCl and that the NaHCO3 proportion of synthetic CBM waters drives toxicity, however other ions are altering the toxicity of bicarbonate.

Inducible defenses of prey are evolved under diverse and variable predation risks. However, during the co-evolution of prey and multiple predators, the responses of prey to antagonistic predation risks, which may put the prey into a dilemma of responding to predators, remain unclear. Based on antagonistic predation pressure from an invertebrate (Chaoborus larvae) and a vertebrate (Rhodeus ocellatus) predator, we studied the responses of multiple traits and transcriptomes of the freshwater crustacean Ceriodaphnia cornuta under multiple predation risks. Chaoborus predation risk altered the expression of genes encoding cuticle proteins and modulated the biosynthesis of steroid hormones, cutin, suberine, and wax, leading to the development of horns and increase in size at the late developmental stage. Meanwhile, fish predation risk primarily triggered genes encoding ribosomes and those involved in unsaturated fatty acid biosynthesis and cysteine and methionine metabolism, resulting in smaller individual size and earlier reproduction. Inducible responses of both transcriptome and individual traits revealed that predator-dependent unique responses were dominant and the dilemma of antagonistic responses was relatively limited. However, the unique individual traits in response to invertebrate predation could be significantly impaired by vertebrate predation risk, even though the unique responses to different predators were extremely weakly correlated and could be elicited simultaneously. These results indicate that diverse predator-dependent unique responses are favored by Ceriodaphnia during its co-evolution with multiple predators. Nonetheless, Ceriodaphnia is not a generalist that can fully adopt all predator-dependent unique responses simultaneously under multiple predation risks.

Deciphering the effects of historical and recent demographic processes responsible for the spatial patterns of genetic diversity and structure is a key objective in evolutionary and conservation biology. Using population genetic analyses, we investigated the demographic history, the contemporary genetic diversity and structure, and the occurrence of hybridization and introgression of two species of anadromous fish with contrasting life history strategies and which have undergone recent demographic declines, the allis shad (Alosa alosa) and the twaite shad (Alosa fallax). We genotyped 706 individuals from 20 rivers and 5 sites at sea in Southern Europe at thirteen microsatellite markers. Genetic structure between populations was lower for the nearly semelparous species A. alosa, which disperses greater distances compared to the iteroparous species, A. fallax. Individuals caught at sea were assigned at the river level for A. fallax and at the region level for A. alosa. Using an approximate Bayesian computation framework, we inferred that the most likely long term historical divergence scenario between both species and lineages involved historical separation followed by secondary contact accompanied by strong population size decline. Accordingly, we found evidence for contemporary hybridization and bidirectional introgression due to gene flow between both species and lineages. Moreover, our results support the existence of at least one distinct species in the Mediterrannean sea: A. agone in Golfe du Lion area, and another divergent lineage in Corsica. Overall, our results shed light on the interplay between historical and recent demographic processes and life history strategies in shaping population genetic diversity and structure of closely related species. The recent demographic decline of these species’ populations and their hybridization should be carefully considered while implementing conservation programs.

Climate change predictions for Southern Europe indicate an increase in the frequency and duration of summer low flows and water scarcity in streams. Droughts can cause substantial changes in aquatic communities and biogeochemical processes because they modify stream environmental conditions. Among the many physical, chemical, and biological variables that influence stream metabolism, nutrients may affect algae and heterotrophic microorganisms, and nutrient concentrations may vary with reduction in water discharge. We experimentally manipulated stream discharge and used a before–after control–impact paired design to assess how reduction of stream discharge affected metabolism (i.e., ecosystem respiration [ER] and gross primary production [GPP]). The study was done in 2 lowland forested streams in northwestern Spain with contrasting nutrient concentrations (i.e., mesotrophic: Caselas stream; eutrophic: Pego stream). In the 2 streams, metabolism was estimated before and after discharge manipulation. Prior to discharge reduction, the 2 streams were heterotrophic (i.e., GPP∶ER < 1), and GPP and ER were related in the eutrophic Pego. Discharge reduction increased GPP at the impacted reaches of the mesotrophic Caselas and decoupled GPP and ER at the Pego. An information-theoretic approach was used to assess which combinations of physical, chemical, and biological variables were most important to explain the variation in ER and GPP under the different hydrologic conditions. The observed differences between the 2 streams suggest that the metabolic response to stream drought can be modulated by the interplay between nutrient availability and the density of consumers feeding on resources, among other environmental variables. We show that longer summer periods and reduced stream discharge have the potential to increase daily hypoxia in nutrient-rich lowland stream ecosystems. Increased hypoxia can threaten biodiversity of stream ecosystems and reduce consumer pressure on basal instream resources, such as algae, bacteria, and fungi, which may, in turn, favor instream GPP. In addition, drying conditions seemed to favor autotrophic over heterotrophic activity under moderate nutrient availability (i.e., increase in the GPP∶ER ratio in the impacted Caselas reaches). Therefore, drought conditions not only affect overall daily rates of metabolic activity, but also the relative importance of different energy sources and organic matter for instream function. Our results show that discharge reduction caused by increased water scarcity, due to both climate change and water demand by human activities, can influence energy flow and organic matter dynamics through effects on the metabolism of forested lowland streams., Funding was provided by the European Union Seventh Framework Programme through the REFRESH project (Adaptive strategies to Mitigate the Impacts of Climate Change on European Freshwater Ecosystems, Grant Agreement 244121).

Higher temperatures can increase metabolic rates and carbon demands of invertebrate herbivores, which may shift leaf-chewing herbivory among plant functional groups differing in C:N (carbon:nitrogen) ratios. Biotic factors influencing herbivore species richness may modulate these temperature effects. Yet, systematic studies comparing leaf-chewing herbivory among plant functional groups in different habitats and landscapes along temperature gradients are lacking. This study was conducted on 80 plots covering large gradients of temperature, plant richness and land use in Bavaria, Germany. We investigated proportional leaf area loss by chewing invertebrates (‘herbivory’) in three plant functional groups on open herbaceous vegetation. As potential drivers, we considered local mean temperature (range 8.4–18.8 °C), multi-annual mean temperature (range 6.5–10.0 °C), local plant richness (species and family level, ranges 10–51 species, 5–25 families), adjacent habitat type (forest, grassland, arable field, settlement), proportion of grassland and landscape diversity (0.2–3 km scale). We observed differential responses of leaf-chewing herbivory among plant functional groups in response to plant richness (family level only) and habitat type, but not to grassland proportion, landscape diversity and temperature—except for multi-annual mean temperature influencing herbivory on grassland plots. Three-way interactions of plant functional group, temperature and predictors of plant richness or land use did not substantially impact herbivory. We conclude that abiotic and biotic factors can assert different effects on leaf-chewing herbivory among plant functional groups. At present, effects of plant richness and habitat type outweigh effects of temperature and landscape-scale land use on herbivory among legumes, forbs and grasses.

In regulatory risk assessment, surrogate species of fish, aquatic invertebrates, and primary producers are tested to assess toxicity and subsequently the risk of pesticides to freshwater biota. This study evaluates whether the standard, surrogate test species (mostly temperate in latitudinal distribution) used in many parts of the world are suitable surrogates for first-tier risk assessments involving tropical freshwater biota. Data for the toxicity of pesticides to tropical fish, invertebrates, and primary producer species were extracted from the USEPA ECOTOX database and peer-reviewed literature. For each pesticide, the most sensitive regulatory endpoint extracted from the US Environmental Protection Agency (USEPA) and European Food Safety Authority (EFSA) dossiers for freshwater fish, invertebrates, and primary producers was selected. The ratios of the endpoint for tropical species and for the most sensitive regulatory endpoint for the appropriate taxonomic group were determined. A value1 indicates that the tropical species is less sensitive than the respective standard regulatory species. Tropical fish species were less sensitive than standard fish species in 84% of the comparisons, and in 93.5% of the comparisons, tropical fish were less or similarly sensitive (within a factor of 5). For aquatic invertebrates, 78.1% of the evaluated tropical species were less sensitive than standard species and 93.3% of tropical invertebrates species were less or similarly sensitive. For primary producers, 96% of tropical species were less sensitive than standard test species. Overall, standard species used globally were more sensitive or similarly sensitive compared to tropical species in more than 93% of the cases. In conclusion, the data show that freshwater toxicity data for pesticides from tests using standard test species, tested according to international accepted guidelines, are appropriate for use in first-tier risk assessments for tropical environments. Integr Environ Assess Manag 2023;19:202-212. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental ToxicologyChemistry (SETAC).

Insects are the most beautiful and wonderful invertebrates having the capability to fly. Apart from the common characteristics of class insects, they have diversity in body structure, size of the body, adaptations, and colourations. The life of social insects, their division of labour, and their rules and regulations are surprising. They adapt themselves successfully to different types of climatic conditions. Sometimes they are beneficial to us and sometimes harmful. In this chapter, we can study the life of insects, the injurious and beneficial insects, and the protective devices of insects. &nbsp

Prepulse inhibition (PPI) is a widely investigated behavior to study the mechanisms of disorders such as anxiety, schizophrenia, and bipolar mania. PPI has been observed across various vertebrate and invertebrate species; however, it has not yet been reported in adult Drosophila melanogaster. In this study, we describe the first detection of PPI of visually evoked locomotor arousal in flies. To validate our findings, we demonstrate that PPI in Drosophila can be partially reverted by the N-methyl D-aspartate (NMDA) receptor antagonist MK-801, known for inducing sensorimotor gating deficits in rodent models. Additionally, we show that the visually evoked response can be inhibited by multiple stimuli presentation, which can also be affected by MK-801. Given the versatility of Drosophila as a model organism for genetic screening and analysis, our results suggest that high-throughput behavioral screenings of adult flies can become a valuable tool for investigating the mechanisms behind PPI.

Aim The objectives of this study were to evaluate which allometric measurements of Leptonema larvae are most suitable in order to develop mathematical equations to describe biomass relationships for the population of this taxon in a reference condition headwater stream. Methods We measured four body dimensions (body length, interocular distance, horizontal width of cephalic capsule and vertical width of the cephalic capsule) of 65 Leptonema larvae, which were collected in February 2022, in the Taboões spring, Serra do Rola Moça State Park, Minas Gerais, using a Surber sampler. For the determination of allometric measurements, each individual was photographed under a dissecting stereomicroscope (Leica M80) equipped with a digital camera. Each photographed specimen's length was measured using the Motic Image Plus 2.0 software. After measuring the linear body dimension and direct measurement of the biomass, we used these values to calculate the length-mass mathematical equations. To the equations use power models: DM = a Lb, where a/b are constants, DM is the dry mass, L is the linear body dimension. Results Among body dimensions of Leptonema larvae, body length showed the greatest range of variation, with values ranging from 4.03 to 25.28 mm, followed by head capsule vertical width (0.51 - 2.69 mm), head capsule horizontal width (0.55 - 2.22 mm) and interocular distance (0.24 - 1.88 mm). Our results show that body length provided the best-fitting equation for estimating biomass (R2 = 0.90). However, we observed a close fit between the other allometric measures, including high coefficients of determination, head capsule horizontal width (R2 = 0.85), interocular distance (R2 = 0.82), head capsule vertical width (R2 = 0.78). Conclusions These results will be useful in providing the best allometric measurement and equations to estimate the biomass of Leptonema larvae from the tropics. Resumo Objetivo Os objetivos deste estudo foram avaliar quais medidas alométricas do corpo das larvas de Leptonema são mais adequadas, a fim de desenvolver equações matemáticas para descrever as relações de biomassa para a população deste táxon em riachos de cabeceira. Métodos Foram medidas quatro dimensões corporais (comprimento corporal, distância interocular, largura horizontal da cápsula cefálica e largura vertical da cápsula cefálica) de 65 larvas de Leptonema, que foram coletadas no mês de fevereiro de 2022, no manancial Taboões, Parque Estadual da Serra do Rola Moça, Minas Gerais, utilizando amostrador Surber. Para a determinação das medidas alométricas, cada indivíduo foi fotografado em um estereomicroscópio dissecante (Leica M80) equipado com câmera digital. O comprimento de cada espécime foi medido usando o software Motic Image Plus 2.0. Após a medição da dimensão corporal linear e medição direta da biomassa, utilizamos esses valores para calcular equações comprimento-massa. Para às equações, usamos modelos de potência: DM = a Lb, onde a/b são constantes, DM é a massa seca, L é a dimensão corporal linear. Resultados O comprimento do corpo apresentou a maior variação, com valores variando de 4,03 a 25,28 mm, seguido pela largura vertical da cápsula cefálica (0,51 - 2,69 mm), largura horizontal da cápsula cefálica (0,55 - 2,22 mm) e distância interocular (0,24 - 1,88 mm). Nossos resultados mostram que o comprimento do corpo forneceu a equação de melhor ajuste para estimar a biomassa (R2 = 0,90). No entanto, observamos um ajuste próximo entre as demais medidas alométricas, retornando altos coeficientes de determinação, largura horizontal da cápsula cefálica (R2 = 0,85), distância interocular (R2 = 0,82), largura vertical da cápsula cefálica (R2= 0,78). Conclusões Esses resultados podem ser úteis para fornecer as melhores medidas alométricas e equações para estimar a biomassa de larvas de Leptonema de riachos tropicais.

Archaeological remains of brachyurans (e.g. crabs) are often overlooked as potential paleoenvironmental and paleoclimatical proxies in contrast to other marine and terrestrial invertebrates such as mollusks and landsnails. The potential for fine-scale regional paleoclimate reconstruction based upon these organisms' behavioral ecology has yet to be examined. We present novel isotopic analyses of the remains of a semiterrestrial freshwater crab (Potamon potamios) endemic to southwest Asia recovered from the archaeological site of Khirbat al-Mudayna al-’Aliya (KMA). KMA lies on a southern tributary of the Wadi al-Mujib in the Hashemite Kingdom of Jordan, approximately 40km east of the Dead Sea. Excavations here recovered architecture, artifacts, and ecofacts dating to a single-period occupation during the early Iron Age (∼1000cal BCE). Oxygen and carbon isotopes from these brachyuran remains were analyzed in conjunction with a two-year isotopic and morphometric study of the modern potomonautid population near the archaeological site and at nearby wadi systems to assess whether the isotopic values of modern crab populations correlated with variables such as temperature, including isotopic study of the pools in which crabs were found. In turn, these data could be used to reconstruct paleoclimate or paleoenvironment in the archaeological population. The high correlation in oxygen isotope values between crab carapaces and the water of the pools in which they were sampled suggest that variability in isotopic values of crab specimens recovered from KMA is tracking ancient human capture of these organisms across potentially different pools. Further, intra-year variability in isotopic values in modern crab carapaces as well as the similarity of isotopic values across wadi systems with different environments suggest thatP. potamiosremains cannot be used as reliable paleoenvironmental indicators. The implications of this research will have significance for archaeologists and other researchers in the study of paleoenvironment and paleoecology, and bears upon human mobility, resource acquisition, and human-nonhuman animal relationships.

The vertebrate eye was described by Charles Darwin as one of the greatest potential challenges to a theory of natural selection by stepwise evolutionary processes. While numerous evolutionary transitions that led to the vertebrate eye have been explained, some aspects appear to be vertebrate specific with no obvious metazoan precursor. One critical difference between vertebrate and invertebrate vision hinges on interphotoreceptor retinoid-binding protein (IRBP, also known as retinol-binding protein, RBP3), which enables the physical separation and specialization of cells in the vertebrate visual cycle by promoting retinoid shuttling between cell types. While IRBP has been functionally described, its evolutionary origin has remained elusive. Here, we show that IRBP arose via acquisition of novel genetic material from bacteria by interdomain horizontal gene transfer (iHGT). We demonstrate that a gene encoding a bacterial peptidase was acquired prior to the radiation of extant vertebrates >500 Mya and underwent subsequent domain duplication and neofunctionalization to give rise to vertebrate IRBP. Our phylogenomic analyses on >900 high-quality genomes across the tree of life provided the resolution to distinguish contamination in genome assemblies from true instances of horizontal acquisition of IRBP and led us to discover additional independent transfers of the same bacterial peptidase gene family into distinct eukaryotic lineages. Importantly, this work illustrates the evolutionary basis of a key transition that led to the vertebrate visual cycle and highlights the striking impact that acquisition of bacterial genes has had on vertebrate evolution.

In the framework of this dissertation, selected biodegradable plastic compounds were investigated for their enzymatic degradability under marine conditions and their impacts on marine invertebrates. The tested compounds are issued from the Horizon 2020 project “Bio-Plastics Europe” and are based on common biodegradable polymers. In-vitro assays showed, that the enzymatic degradability of these compounds is impaired by low temperatures prevailing in the ocean. Additionally, almost no degradation was observed with exposure experiments in seawater and mud for six months, indicating no or only very slow degradation of biodegradable plastics in most marine environments. Feeding experiments with different marine invertebrates showed, that biodegradable microplastics are ingested in the same way as conventional microplastics. Once ingested, they might be exposed to digestive enzymes. Gastric fluids from the edible crab Cancer pagurus and the American lobster Homarus americanus were incubated with microplastics and the hydrolysis was measured, showing that both species can potentially hydrolyze one of the biodegradable plastics. Further analyses of the gastric fluid of the edible crab identified high activities of carboxylesterases, which are thought to be responsible for the hydrolysis of the biodegradable plastic. The implications following an ingestion of biodegradable microplastics were investigated using the rockpool shrimp Palaemon elegans. Acute feeding trials and also continuous feeding of microplastics did not induce oxidative stress in the shrimp. However, ingestion of one of the materials led to increased carboxylesterase activity in all experiments. Furthermore, the effects of substances that potentially leach out of biodegradable plastics were investigated with marine zooplankton. Leachates from one of the compounds induced high mortalities in the rotifer Brachionus plicatilis and in nauplii from the brine shrimp Artemia persimilis, indicating the presence of toxic additives.

This volume deals exlusively with the results of the research field trip of the Humboldt-Universität zu Berlin to the AWI Wattenmeerstation List, Sylt (Germany) from 27.09. - 05.10.2022

Marine intertidal hard substrates provide an ecologically important habitat for many sessile or semi-sessile organisms. As shelter, food source, nursery or living space, they are of central importance in marine ecosy- stems worldwide (Bellan-Santini et al., 1994). Particularly in the Wadden Sea, dominated by soft substrates and extensive tidal flats, the few hard substrates are essential to many sessile organisms. Therefore, such habitats require special protection. During the last forty years, the pacific oyster became more dominant in the North Sea. While it appears to be in compe- tition with the blue mussel, it could provide potential new niches for sessile organisms, on the other side (Dietrich, 2005). This study aims to make a comparative investigation of the biodiversity on the different types of hard substrates in the intertidal zone of the North Sea on Sylt Island. In total, 53 species belonging to three different ecological guilds (algae, sessile and mobile animals) could be documented on four dif- ferent substrates under two conditions. Besides the attached species’ list, different ecological parameters were calculated, including species abundance, Evenness, and the Shannon-Wiener Index (H). The latter was highest for rocks from the rock-blue mussel reef and lowest in detached rocks taken from the mudflat. In bivalves, the observed biodiversity in sessile organisms was higher in pacific oysters than it was on blue mussels. The opposite is true for mobile organisms, which showed a higher biodiversity on blue mussels found in reef than on isolated oysters. This study has shown that the isolated oysters provide a comparable biodiverse habitat for species living on hard substrate in the Wadden Sea, showing a comparable biodiversity. The native blue mussel as well as the rock reefs shows a great abundance of species, being a shelter for specialist taxa like the hydrozoans. In contrast to the expectations, the oysters offer living space for many native taxa. Therefore, as an extension to the original habitats, they might represent an enrichment of the hard substrate habitat in the Wadden sea on Sylt.

This volume deals exlusively with the results of the research field trip of the Humboldt-Universität zu Berlin to the AWI Wattenmeerstation List, Sylt (Germany) from 04.04. - 15.04.2022

BACKGROUND: The data we present are part of the CUARENTAGRI project, which involves all archipelagos of the Macaronesia (Azores, Madeira, Canary Islands and Cabo Verde). The project aims to: i) identify and evaluate the risks associated with the introduction of new arthropod pests; ii) study the population dynamics of selected arthropod pest species currently responsible for the damage of key target crops and iii) develop monitoring systems, based on prediction and/or population dynamics of the crop pests, creating warnings and a phytosanitary prevention system. In this contribution, we compile data for three Azorean Islands (Terceira, São Jorge and São Miguel Islands), where pheromone-baited traps were placed in pastures, potato fields and several orchards’ types (apples, banana, chestnuts, olives, orange and strawberry), during three consecutive years (2020, 2021 and 2022). NEW INFORMATION: A total of 114,827 specimens of insects (Arthropoda, Insecta) were collected, belonging to four orders, six families and ten recorded pest species. A total of eight species are considered introduced (Cosmopolites sordidus (Germar, 1824), Drosophila suzukii (Matsumura, 1931), Bactrocera oleae (Rossi, 1790), Ceratitis capitata (Wiedemann, 1824), Phthorimaea operculella (Zeller, 1873), Cydia pomonella (Linnaeus, 1758), Cydia splendana (Hübner, 1799) and Grapholita molesta (Busck, 1916); n = 84,986 specimens) and two native non-endemic (Mythimna unipuncta (Haworth, 1809) and Spodoptera littoralis (Boisduval, 1833); n = 17,465 specimens). This study intended to contribute to a better knowledge of the arthropods pests that can affect the Azorean crops and will serve as a baseline for future monitoring actions, pest risk assessments and prevention systems. This work was financed under the project CUARENTAGRI by Cooperation Programs INTERREG V A (Spain-Portugal) and MAC 2014-2020. Darwin Core Database management was funded by the Project project FCT-UIDB/00329/2020-2024 (Thematic Line 1 – integrated ecological assessment of environmental change on biodiversity) and Portal da Biodiversidade dos Açores (2022-2023) - PO Azores Project - M1.1.A/INFRAEST CIENT/001/2022. Lucas Lamelas-Lopez was supported by the Project FCT-UIDP/00329/2020-2023. info:eu-repo/semantics/publishedVersion

Invertebrates such as Asellus aquaticus, halacarid mites, copepods and cladocerans are common in drinking water distribution systems. The Zeeuws-Vlaanderen drinking water distribution system (DWDS) of Evides water company is divided into western and eastern sections, initially supplied with drinking water derived from a eutrophic reservoir (water) and groundwater, respectively. The drinking water derived from eutrophic reservoir water was characterised as less biologically stable than the drinking water from groundwater. Due to groundwater level protection measures, since 2015 the groundwater supply to the eastern section has been gradually replaced with supply from the drinking water treatment plant, which uses eutrophic reservoir water as source water. This change caused increased regrowth conditions, as observed by regulated microbial regrowth indicators (HPC22 and Aeromonas), increased invertebrate biomass, and the dominant occurrence of Asellus aquaticus, confirming observations in other Evides DWDSs. The results from the western section supplied with the same less biological stable drinking water, however, showed that the occurrence of microbial regrowth, invertebrate biomass and A. aquaticus is not only related to the biological stability of the supplied drinking water, but also to the influence of DWDS-specific conditions. The DWDS configuration as well as higher water demands in summer (western section) and/or higher sediment and Fe accumulation in the DWDS (eastern section) are suggested factors affecting regrowth and therefore subjects for further research.

Coastal lagoon ecology often changes on progression from the open, well-flushed mouth region to the depositional zone furthest from the open sea. This is generally considered consequent on increasing 'confinement' and associated features, rather than on the often co-occurringly decreasing salinity. The 12 km Rainbow Channel connecting part of Moreton Bay, a microtidal leaky lagoon, to the adjacent Pacific provides a gradient of increasing confinement without any significant salinity change, i.e. a tenfold increase in water residence time for a salinity decrease of