Meta-analysis contrasting freshwater biodiversity in forests and oil palm plantations with and without riparian buffers.

The expansion of oil palm plantations has led to land-use change and deforestation in the tropics, which has affected biodiversity. Although the impacts of the crop on terrestrial biodiversity have been extensively reviewed, its effects on freshwater biodiversity remain relatively unexplored. We reviewed the research assessing the impacts of forest-to-oil palm conversion on freshwater biota and the mitigating effect of riparian buffers on these impacts. We searched for studies comparing taxa richness, species abundance, and community composition of macroinvertebrates, amphibians, and fish in streams in forests (primary and disturbed) and oil palm plantations with and without riparian buffers. Then, we conducted a meta-analysis to quantify the overall effect of the land-use change on the 3 taxonomic groups. Twenty-nine studies fulfilled the inclusion criteria. On average, plantations lacking buffers hosted 44% and 19% fewer stream taxa than primary and disturbed forests, respectively. Stream taxa on plantations with buffers were 24% lower than in primary forest and did not differ significantly from disturbed forest. In contrast, stream community composition differed between forests and plantations regardless of the presence of riparian buffers. These differences were attributed to agrochemical use and altered environmental conditions in the plantations, including temperature changes, worsened water conditions, microhabitat loss, and food and shelter depletion. On aggregate, abundance did not differ significantly among land uses because increases in generalist species offset the population decline of vulnerable forest specialists in the plantation. Our results reveal significant impacts of forest-to-oil palm conversion on freshwater biota, particularly taxa richness and composition (but not aggregate abundance). Although preserving riparian buffers in the plantations can mitigate the loss of various aquatic species, it cannot conserve primary forest communities. Therefore, safeguarding primary forests from the oil palm expansion is crucial, and further research is needed to address riparian buffers as a promising mitigation strategy in agricultural areas.

Metaanálisis contrastando la biodiversidad de agua dulce en los bosques y las plantaciones de palma de aceite con o sin bosques ribereños Resumen La expansión de las plantaciones de palma de aceite ha derivado en cambios en el uso de suelo y deforestación en los trópicos, afectando a la biodiversidad. Existe una revisión extensa del impacto de este cultivo sobre la biodiversidad terrestre, pero sus efectos sobre la biodiversidad de agua dulce todavía no están muy documentados. Revisamos las investigaciones que han evaluado el impacto de la conversión de bosque a plantación de palma de aceite sobre la biota de agua dulce y el efecto mitigante que tienen los bosques ribereños sobre este impacto. Buscamos estudios que compararan la riqueza de taxones, abundancia de especies y composición comunitaria de los macroinvertebrados, anfibios y peces en los riachuelos de los bosques (primarios y perturbados) y los sembradíos de palma de aceite con y sin bosques ribereños. Después realizamos un metaanálisis para cuantificar el efecto del cambio de uso de suelo en los tres grupos taxonómicos. Veintinueve estudios cumplieron con el criterio de inclusión. En promedio, las plantaciones carentes de bosques ribereños albergaron 44% y 19% menos taxones que los bosques primarios y perturbados. Los taxones en los sembradíos con bosques ribereños fueron 24% menos que en el bosque primario y no difirieron significativamente del bosque perturbado. Como contraste, la composición comunitaria del riachuelo difirió entre los bosques y los sembradíos sin importar la presencia de los bosques ribereños. Atribuimos estas diferencias al uso de agroquímicos y las condiciones ambientales alteradas en las plantaciones, incluidas los cambios térmicos, condiciones hidrológicas alteradas, pérdida de microhábitats y reducción de alimentos y refugios. En general, la abundancia no difirió significativamente entre los usos de suelo porque el incremento de especies generalistas en las plantaciones contrarresta la declinación poblacional de los especialistas de bosque vulnerables. Nuestros resultados revelan un impacto significativo de la conversión de bosque a plantación sobre la biota de agua dulce, particularmente la riqueza de taxones y la composición (pero no la abundancia agregada). Aunque mantener los bosques ribereños en las plantaciones puede mitigar la pérdida de varias especies acuáticas, no puede conservar las comunidades del bosque primario. Por lo tanto, es crucial salvaguardar los bosques primarios de la expansión del aceite de palma, además de que se necesitan más investigaciones para abordar los bosques ribereños como una estrategia prometedora de mitigación en las áreas agrícolas.

Main drivers of dragonflies and damselflies (Insecta; Odonata) metacommunities in streams inside protected areas in the Brazilian Amazon.

The evaluation of environmental and spatial influence in freshwater systems is crucial for the conservation of aquatic diversity. So, we evaluated communities of Odonata in streams inside and outside sustainable use areas in the Brazilian western Amazon. We predicted that these streams would differ regarding habitat integrity and species α and ß diversity. We also predict that environmental and spatial variables will be important for both suborders, but with more substantial effects on Zygoptera species, considering their nature of forest-specialist. The study was conducted in 35 streams, 19 inside and 16 outside sustainable use areas. The streams outside presented high species richness, abundance, and number of exclusive forest-specialist species from Zygoptera and higher scores of habitat integrity. In contrast, one sustainable use area presented the lowest values of these metrics. Besides, we found that environmental and spatial variables were significantly associated to Zygoptera species composition, but not with Anisoptera, which can be explained by their cosmopolitan nature. Our results indicated that an interplay between environmental and spatial processes determines the structure of the metacommunities of Zygoptera. The less effective dispersal rates and narrow ecological tolerance of Zygoptera species make them more influenced by local conditions and dispersal limitation, and more sensible to habitat modifications. We highlight the importance of improving the local management of the sustainable use areas by environmental agencies, mainly on areas that are losing their capacity to maintain the aquatic fauna, and implementation of social policies toward traditional people.

Human land-uses homogenize stream assemblages and reduce animal biomass production.

Human land-use change is a major threat to natural ecosystems worldwide. Nonetheless, the effects of human land-uses on the structure of plant and animal assemblages and their functional characteristics need to be better understood. Furthermore, the pathways by which human land uses affect ecosystem functions, such as biomass production, still need to be clarified. We compiled a unique dataset of fish, arthropod and macrophyte assemblages from 61 stream ecosystems in two Neotropical biomes: Amazonian rainforest and Uruguayan grasslands. We then tested how the cover of agriculture, pasture, urbanization and afforestation affected the taxonomic richness and functional diversity of those three species assemblages, and the consequences of these effects for animal biomass production. Single trait categories and functional diversity were evaluated, combining recruitment and life-history, resource and habitat-use, and body size. The effects of intensive human land-uses on taxonomic and functional diversities were as strong as other drivers known to affect biodiversity, such as local climate and environmental factors. In both biomes, the taxonomic richness and functional diversity of animal and macrophyte assemblages decreased with increasing cover of agriculture, pasture, and urbanization. Human land-uses were associated with functional homogenization of both animal and macrophyte assemblages. Human land-uses reduced animal biomass through direct and indirect pathways mediated by declines in taxonomic and functional diversities. Our findings indicate that converting natural ecosystems to supply human demands results in species loss and trait homogenization across multiple biotic assemblages, ultimately reducing animal biomass production in streams.

Trap and bait efficiency for catching Calliphoridae and Mesembrinellidae (Insecta, Diptera) at different heights.

The influence of food types, reproductive behaviour, and the existence of a possible stratification to the attractiveness of Calliphoridae and Mesembrinellidae flies may contribute to the definition of collection methodologies. Thus, we assessed the effectiveness of traps with two bait types exposed at two different heights in the forests for collecting the aforementioned families. Traps were exposed in the Amazon rainforest floodplain area, where 40 traps were installed in 20 trees, in three periods of the year. On each tree, one trap was installed at 0.6 m and the other at 10 m above the ground, with either bovine lung or fermented banana. A total of 1,173 individuals were collected, including 10 species of Calliphoridae (962 individuals) and four species of Mesembrinellidae (211 individuals). Of the total in each family, Calliphoridae was most abundant in 0.6m lung bait traps (41%) and Mesembrinellidae in the 0.6 m banana bait traps (29%). Calliphoridae showed greater species richness, abundance, and differentiation in composition in low traps with lung as bait. In conclusion, only dipteran species from Calliphoridae have been affected and responded the collection methodologies employed of we, which may highlight remarkable differences in collection and subsequent data interpretation of inventories and monitoring using these insects.

Does land use and land cover affect adult communities of Ephemeroptera, Plecoptera and Trichoptera (EPT)? A systematic review with meta-analysis.

We conducted a systematic review to better understand this gap and analyzed i) in which global regions are studies usually conducted, ii) the taxon studied, iii) sampling methods and iv) how authors collaborated in these studies. We also tested the relationship between different types of land use and land cover and adult EPT communities using a meta-analysis. We searched for relevant articles on the website Web of Science, using specific words related to the subject. We found 454 papers and selected 31 of them for the scientometric analysis, as they were in accordance with our objectives, and eight for the meta-analysis. Among this subset, we observed that study areas and collaborations among authors were largely restricted to a few countries in Europe and North America. Most studies used the group Trichoptera, probably due to its diversity and the longevity of the adults compared to other groups. Light traps were the most common sampling method, most likely due to their efficiency in capturing flying insects with nocturnal habits. The greatest differences in adult EPT communities were found between open areas (moorland and prairie) and forest areas. This result indicated that the conversion of forest habitats into open areas negatively impacts adult EPT communities. Our systematic review can be an important tool to help researchers choose appropriate collection methods and taxonomic groups to work with in studies on impacts of land use change on adult EPT communities.

Environmental thresholds of dragonflies and damselflies from a Cerrado-Caatinga ecotone.

Aquatic ecosystems are affected by different land uses that modify gradients of environmental conditions. These impacts act directly on the community structure, especially the most sensitive ones, such as aquatic insects. Thus, dragonflies have been used as good models to assess these changes, since their suborders Anisoptera and Zygoptera have different ecophysiological and behavioral requirements. This study aimed to evaluate the following hypotheses: (1) dragonfly species composition differs along the environmental gradients of streams; therefore, we expect a higher proportion of species of the suborder Anisoptera in environments with a higher degree of disturbance, since these environmental conditions select heliothermic species with exophytic oviposition; (2) the reduction of habitat integrity and canopy cover will lead to a lower richness of the Zygoptera suborder, due to the restrictions of its thermoregulation and oviposition behavior in relation to Anisoptera, since the higher light input would favor heliothermic and exophytic species; (3) alterations in habitat integrity create ecological thresholds and points of change in the abundance and frequency of Odonata species, generating gradients in the environmental integrity conditions. Specimens were collected from 24 streams (first to third order), in a gradient of land uses. Canopy cover and stream width were predictors of taxonomic richness and abundance of the suborders Anisoptera and Zygoptera, with greater coverage and smaller width, positively affecting Zygoptera and negatively Anisoptera. The turning points were determined by a habitat integrity index, where below 0.38 there is an increase in generalist taxa and a decline in sensitive taxa. On the other hand, above 0.79, there was a sensitive taxa increase in detriment of generalists. Four individual taxa indicators were selected, two of which associated with a negative response (Perithemis tenera and Acanthagrion aepiolum) and two with positive responses (Epipleoneura metallica and Zenithoptera lanei) for habitat integrity. Our results are important to guide management strategies, recovery, and protection policies for areas of permanent protection, aiming to conserving biodiversity and natural resources essential to life quality maintenance.

Response of aquatic insects to an environmental gradient in Amazonian streams.

The increasing land use in the Amazon region has resulted in the widespread substitution of forest areas with pasture and bauxite mining. These land uses reduce the forest cover of streams and modify their characteristics, reducing the diversity of aquatic insect assemblages. In the present study, we aimed to identify the threshold of the assemblages of the larvae of insects of the orders Ephemeroptera, Plecoptera, and Trichoptera (collectively known as EPT), and adults of the order Odonata, along an environmental gradient of land use and land cover (LULC). We sampled 30 streams along an environmental gradient determined by the proportion of forest, pasture, and bauxite mining observed within the catchment of each stream. We identified 12 taxa associated with forest (nine positively and three negatively) and four negatively associated with pasture. However, no taxa were associated explicitly with the bauxite mining gradient. As forest is converted to pasture, the abundance and frequency of occurrence of the taxa sensitive to pasture are reduced, reflecting their environmental sensitivity and their potential as sentinels of preserved streams. The identification of the thresholds of the EPT and odonates taxa allowed us to determine which of these organisms are positively or negatively associated with the environmental gradient of LULC in Amazonian streams. We hope that the results of the present study can be applied in future biomonitoring programs, particularly for monitoring the response of aquatic insects to the degradation of streams.

Erythrodiplax nataliae sp. nov., a new species for the state of Mato Grosso, Brazil.

Erythrodiplax nataliae sp. nov. (5 males), collected in Vereda wetlands (a unique Neotropical savanna environment) in Mato Grosso, Brazil is described and illustrated. The new species fits in Borror's Juliana Group, and can be distinguished from other species by the combination of the following traits: blue pruinosity on thorax (more dense dorsally); sides of the pterothorax yellowish, darkening dorsally; face ivory, dorsally black with a metallic blue reflection; wings hyaline with a small basal brown spot; vesica spermalis with long lateral lobes, enclosing the median process and median process elongated with a pair of conspicuous rectangular and elongated lateral lobes, with a middle dorso-ventral furrow.

Aquatic insects and their environmental predictors: a scientometric study focused on environmental monitoring in lotic environmental.

Since early studies about aquatic ecology, it has been found that changes in environmental conditions alter aquatic insect communities. Based on this, the combined study of environmental conditions and aquatic insect communities has become an important tool to monitor and manage freshwater systems. However, there is no consensus about which environmental predictors and facets of diversity are more useful for environmental monitoring. The objective of this work was to conduct a scientometric analysis to identify the main environmental predictors and biological groups used to monitor and manage lotic freshwater systems. We conducted a scientometric study on the Web of Science platform using the following words: stream, river, aquatic insect, Ephemeroptera, Plecoptera, Trichoptera, Odonata, Heteroptera, Chironomidae, bioindicator, environmental change, anthropic, and land use. Although most of the environmental predictors employed are local, intrinsic of freshwater systems using local environmental and associated landscape variables is a better strategy to predict aquatic insect communities. The facets of diversity most used are composition and richness of species and genera, which are not efficient at measuring the loss of ecosystem services and extinction of phylogenetic lineages. Although very important, these functional and phylogenetic facets are poorly explored for this purpose. Even though tropical regions are the most diverse globally and are experiencing major losses of native vegetation, these ecosystems are the least studied, a knowledge gap that needs addressing to better understand the effect of anthropogenic activities on the diversity of aquatic insects.

Evaluating the habitat integrity index as a potential surrogate for monitoring the water quality of streams in the cerrado-caatinga ecotone in northern Brazil.

Human activities have long been altering the natural conditions of streams, including the quality of their water, throughout most of Brazil. This problem is even worse in regions with low rainfall levels, such as the Brazilian Northeast, where water quality needs to be monitored more carefully. In this context, the present study investigated the effects of environmental integrity on the physicochemical characteristics of the streams of the basin of the Itapecuru River in northeastern Brazil. We tested the hypothesis that streams with lower habitat integrity would have higher conductivity, pH, and temperature, due to the reduced input of allochthonous organic matter and the greater washout of sediments to the stream bed. A total of 15 streams, of a sedimentary basin, were evaluated in the municipality of Caxias, in the Brazilian state of Maranhão, between June 2015, and July 2016; each stream was sampled once a month during the drought period in the region, where physicochemical measurements were taken to determine the environmental integrity of the stream through the application of a habitat integrity index. Streams with greater habitat integrity had lower conductivity, pH, and temperature and had higher discharge rates. The index proved to be not an effective tool for the evaluation of water quality, but was found to be important for the management of hydrographic basins by indicating important changes in environmental variables. In this case, the index can be used primarily for the management of hydrographic basins, given that it can be applied straightforwardly, it can be interpreted easily by decision-makers, and it can quantify alterations to the structure of the system with precision.

Effect of oil palm on the Plecoptera and Trichoptera (Insecta) assemblages in streams of eastern Amazon.

The production of oil palm is expected to increase in the Amazon region. However, expansion of oil palm plantation leads to significant changes in the physical structure of aquatic ecosystems, mainly through the reduction of riparian vegetation that is essential for aquatic biodiversity. Here, we evaluated the effects of oil palm on the physical habitat structure of Amazonian stream environments and assemblages of Plecoptera and Trichoptera (PT), ​both found in these streams. We compared streams sampled in oil palm plantations (n = 13) with natural forest areas ("reference" streams, n = 8), located in the eastern Amazon, Brazil. Our results showed that oil palm streams were more likely to be in close proximity to roads, had higher pH values, and higher amounts of fine substrate deposited in the channel than reference streams. Further, these environmental changes had important effects on the aquatic invertebrate assemblages, reducing the abundance and richness of PT. Nevertheless, the genera composition of the assemblages did not differ between reference and oil palm (PERMANOVA, pseudo-F (1,19) = 1.891; p = 0.111). We conclude that oil palm production has clear negative impacts on aquatic environments and PT assemblages in Amazonian streams. We recommend that oil palm producers invest more in planning of road networks to avoid the construction of roads near to the riparian vegetation. This planning can minimize impacts of oil palm production on aquatic systems in the Amazon.

Little effects of reduced-impact logging on insect communities in eastern Amazonia.

Selective logging has become a major source of threats to tropical forest, bringing challenges for both ecologists and managers to develop low-impact forestry. Reduced-impact logging (RIL) is a prominent activity accounting for such forestry practices to prevent strong forest disturbances. Our aims were to evaluate the effects of RIL on insect communities of forested streams from Eastern Amazon and to test the hypothesis of negative effects of RIL on species richness, abundance, and functional feeding groups of aquatic insect assemblages. Neither of the evaluated metrics of the studied assemblages were negatively affected by RIL. Environmental metrics, such as substrate heterogeneity, woody canopy cover, and hill slope height, varied more among RIL streams than in reference streams, indicating a gradient according to logging impacts, and are suitable candidates to monitor RIL impacts in Amazonian streams. In addition, the PHI index also varied among REF and RIL, according to age class and year of logging, which could reflect trends to recover the forest structure after logging in a time frame of only 10 years. We conclude that RIL impacts have not had detrimental impacts on insect communities, but have changed little of the environmental conditions, especially of the riparian vegetation around streams.

Setting boundaries: environmental and spatial effects on Odonata larvae distribution (Insecta).

Environmental characteristics and spatial distances between sites have been used to explain species distribution in the environment, through Neutral (space) and Niche theory (environment) predictions. We evaluated the effects of spatial and environmental factors on Odonata larvae distribution along the Suiá-Missú River Basin, state of Mato Grosso. We tested the hypotheses that (1) the environment is the main factor structuring the community due to its ecophysiological requirements; and (2) the pattern, if present, is clearer for Zygoptera. Samples were made in 12 sites on the Suiá-Missú River Basin in three seasons (2007/2008), with a total of 1.382 Odonata larvae, comprising 10 families, 51 genera and 100 morphospecies. The Anisoptera were more abundant than Zygoptera, comprising 81% of all specimens. The environment affected Zygoptera (R=0.291; p=0.007) and was the main factor structuring the assembly. Thus, Niche theory was confirmed. The absence of this effect on Anisoptera may be due to the ecophysiological adaptations that enable it to occupy different habitats. Zygoptera larvae are indicators of changes in habitat structure. The effects of environmental variables on larvae ecology emphasize the strong relationship between these organisms and environmental integrity.

The potential uses of sarcosaprophagous flesh flies and blowflies for the evaluation of the regeneration and conservation of forest clearings: a case study in the Amazon forest.

The level of association between dipterans of the families Calliphoridae and Sarcophagidae and habitats with different levels of vegetation cover was analyzed at Porto Urucu in Coari, Amazonas, Brazil, with the aim of identifying the potential of these taxa as bioindicators for the assessment of forest regeneration and conservation. The flies were collected in 16 sample areas, 12 of which were clearings at different stages of regeneration (C1--early regeneration; C2--moderate regeneration; and C3--advanced regeneration) and 4 in continuous forest (F). According to the IndVal analysis, nine sarcophagid species--Peckia (Sarcodexia) lambens (Wiedemann), Peckia (Peckia) chrysostoma (Wiedemann), Peckia (Squamatodes) ingens (Walker), Sarcofahrtiopsis cuneata (Townsend), Oxysarcodexia thornax (Walker), Peckia (Euboettcheria) collusor (Curran & Walley), Oxysarcodexia fringidea (Curran & Walley), Oxysarcodexia amorosa (Schiner), and Helicobia pilifera (Lopes)--were associated indiscriminately with clearings (C1 + C2 + C3). In contrast, only one calliphorid species Chrysomya albiceps (Wiedemann) was associated with clearings in the early moderate regeneration (C1 + C2) phases, and four calliphorids were associated with continuous forest or mature clearings (C3 + F): Mesembrinella bicolor (F.), Eumesembrinella randa (Walker), Mesembrinella bellardiana (Aldrich), and Lucilia eximia (Wiedemann). These results indicate that sarcophagids may be useful for evaluating the degree of anthropogenic impact but are not suitable for the detection of minor variations in forest cover. In contrast, calliphorids may be appropriate for the evaluation of both anthropogenic impacts and the degree of forest regeneration and conservation.

Behavioral Diversity Among Odonata Larvae Increases in Water with Greater Turbidity Under Captivity Conditions.

Various factors, including environmental variables, influence the behavior of aquatic insects. However, our understanding of insect behavior and their relationships with these variables remains limited. One important variable is water turbidity, which may be exacerbated by soil erosion, directly impacting visibility in the water and potentially affecting the organism's behaviors. In this study, we investigated larval behavior across seven Odonata species under controlled conditions, examining variations in behavioral diversity (frequency and type) associated with sex and three levels of water turbidity. Our findings revealed that heightened water turbidity correlated with increased behavior frequency, possibly attributable to predator avoidance in darker, seemingly safer habitats. Furthermore, behavior diversity differed between sexes, being higher for males in certain categories and for females in others. Anisoptera species predominantly displayed behaviors like resting, eating, and prey capture, whereas Zygoptera larvae were often observed perching and walking, possibly indicative of distinct predator response strategies. Behaviors shared by Anisoptera larvae could be associated with similar responses to predators and capture of prey. Our study found an increased frequency of behaviors when the larvae are in water with higher turbidity. Behavior frequency disparities between the sexes were observed across various behaviors, likely influenced by species-specific activity levels and individual behavioral plasticity in response to environmental cues. Overall, individuals exhibited heightened behavioral activity in environments with elevated turbidity, potentially reflecting a perceived lower risk environment.

Variations in the Odonata Assemblages: How Do the Dry Season and Water Bodies Influence Them?

Diverse abiotic and biotic factors drive the ecological variation of communities across spatial and temporal dimensions. Within the Amazonian landscape, various freshwater environments exhibit distinct physicochemical characteristics. Thus, our study delved into the fluctuations of Odonata assemblages amidst distinct water bodies within Amazonia, encompassing two distinct climatic seasons. Comparative analysis was conducted on Odonata species diversity and assemblage composition across a blackwater pond, a lake, and a stream, spanning the initiation and culmination of the dry season in the southwestern Amazon region in Peru. Our methodology involved capturing adult Odonata using entomological nets on three separate occasions between 11:00 and 14:00 h for each water body in May (beginning of the dry season) and October (end of the dry season) of 2018. We also evaluated the influence of temperature, precipitation, and percent cloud cover on the abundance and richness of adult Odonata. Species richness and composition differed among the three water bodies in both periods of the dry season. No effect of the dry season periods on species richness and abundance was observed. However, except in the oxbow lake, the more abundant species were substituted to the end of the dry season. Our study highlights the influence of water body types on Odonata species diversity and composition. The effects of the sampling period during the dry season may not be immediately apparent in conventional diversity metrics, such as species richness and abundance. Instead, its effects manifest predominantly in the relative abundance of the species that compose these assemblages.

Do Methodological Differences in Experiments with Stream Shredders Imply Variability in Outputs? A Microcosm Approach.

Experiments are useful scientific tools for testing hypotheses by manipulating variables of interest while controlling for other factors that can bias or confuse the results and their interpretation. To ensures accuracy and reproducibility, experiments must have transparent and repeatable methodologies. Due to the importance of shredder invertebrates in organic matter processing, carbon cycling, and nutrient cycling, we tested experimentally the effect of different methodological approaches in microcosm experiments on the consumption and survival of shredders. We found that the shredder species, the presence or absence of the case, and the use or non-use of air-pumps in the microcosms did not affect shredder performance (i.e., consumption and survival). Furthermore, the type of water (stream or bottled) did not affect shredder performance. On the other hand, the amount of light had a negative effect on shredder performance, with constant light (i.e., 24 h) reducing shredder consumption and survival. Our results demonstrate that the use of different methodologies does not always result in changes in outcomes, thus ensuring comparability. However, luminosity is a critical factor that deserves attention when conducting microcosm experiments. Our findings provide valuable insights that can assist researchers in designing experiments with shredders from neotropical streams and conducting systematic reviews and meta-analyses.

Trichoptera Life Stages Present Distinct Responses to Environmental Conditions in Amazonian Streams.

Biological communities have their biodiversity patterns affected by environmental, spatial, and biogeographic factors that vary from taxa to taxa, and often between life stages. This is especially true when there are differences in the habitat the species use in each of them. Individuals of the insect order Trichoptera are mostly aquatic in their larval stage and terrestrial in their adult stage, which may result in different behaviors and environmental requirements. Our goal was to evaluate the congruence between the larval and adult stages of Trichoptera in Amazonian streams regarding their abundance, richness, and assemblage composition. Additionally, we tried to identify the main environmental factors related to each life stage. For this, larvae and adults of Trichoptera were sampled in the same sites at 12 streams in the Caxiuanã National Forest, Pará state, Brazil. Adult assemblages had greater richness of genera and abundance of individuals than the larval ones, and there was no congruence in the genera composition between these life stages. Our results also showed that different environmental variables structured Trichoptera larvae and adults. Since the sampling of larvae and adults proved to be complementary in the studied streams, we advise that Trichoptera diversity surveys consider both life stages of these organisms.

Total environment sentinels: Dragonflies as ambivalent/amphibiotic bioindicators of damage to soil and freshwater.

Discerning the impact of anthropogenic impacts requires the implementation of bioindicators that quantify the susceptibilities and vulnerabilities of natural terrestrial and aquatic ecosystems to perturbation and transformation. Although legal regulations in Brazil recognize the value of bioindicators in monitoring water quality, the depreciation of soil conditions has yet to receive adequate attention. Thus, our study aimed to evaluate the potential of odonates (dragonflies and damselflies) as amphibiotic bioindicators to reflect the correlation between the degradation of aquatic and terrestrial habitats in pasture-dominated landscapes. We assessed the relationship between the biotic indices of Odonata and the conservation status of preserved riparian landscapes adjacent to anthropogenically altered pastures in 40 streams in the Brazilian savannah. Our results support the hypothesis that Odonata species composition may be a surrogate indicator for soil and water integrity, making them promising sentinels for detecting environmental degradation and guiding conservation strategies in human-altered landscapes. Importantly, while the Zygoptera/Anisoptera species ratio is a useful bioindicator tool in Brazilian forest, it is less effective in the open savannah here, and so an alternative index is required. Importantly, while the Zygoptera/Anisoptera species ratio is a useful bioindicator tool in Brazilian forest, it is less effective in the open savannah here, and so an alternative index is required. On the other hand, our results showed the Dragonfly Biotic Index to be a suitable tool for assessing freshwater habitats in Brazilian savannah. We also identified certain bioindicator species at both ends of the environment intactness spectrum.

Systematic challenges and opportunities in insect monitoring: a Global South perspective.

Insect monitoring is pivotal for assessing biodiversity and informing conservation strategies. This study delves into the complex realm of insect monitoring in the Global South-world developing and least-developed countries as identified by the United Nations Conference on Trade and Development-highlighting challenges and proposing strategic solutions. An analysis of publications from 1990 to 2024 reveals an imbalance in research contributions between the Global North and South, highlighting disparities in entomological research and the scarcity of taxonomic expertise in the Global South. We discuss the socio-economic factors that exacerbate the issues, including funding disparities, challenges in collaboration, infrastructure deficits, information technology obstacles and the impact of local currency devaluation. In addition, we emphasize the crucial role of environmental factors in shaping insect diversity, particularly in tropical regions facing multiple challenges including climate change, urbanization, pollution and various anthropogenic activities. We also stress the need for entomologists to advocate for ecosystem services provided by insects in addressing environmental issues. To enhance monitoring capacity, we propose strategies such as community engagement, outreach programmes and cultural activities to instill biodiversity appreciation. Further, language inclusivity and social media use are emphasized for effective communication. More collaborations with Global North counterparts, particularly in areas of molecular biology and remote sensing, are suggested for technological advancements. In conclusion, advocating for these strategies-global collaborations, a diverse entomological community and the integration of transverse disciplines-aims to address challenges and foster inclusive, sustainable insect monitoring in the Global South, contributing significantly to biodiversity conservation and overall ecosystem health. This article is part of the theme issue 'Towards a toolkit for global insect biodiversity monitoring'.