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Interspecific hybridization plays an important role in plant evolution, contributing to taxonomic uncertainty through intermediate phenotypes or the emergence of novel traits. The characterization of hybridization is important to elucidate systematic relationships and its role in the diversification of lineages. The genus Cenostigma comprises neotropical legume trees with phylogenetic inconsistencies, and individuals showing intermediate morphology between sympatric species, suggesting natural hybridization. We tested this hypothesis by investigating two endemic species from the Caatinga dry forest in northeast Brazil (C. microphyllum and C. pyramidale) using molecular markers (nuclear and plastid SSRs), geometric morphometrics, non-targeted metabolomics, and ecological analyses. We detected a high plastidial genetic structure among populations, not related to species boundaries but to their geographic distribution. The geometric morphometric analysis showed a clustering of pure individuals of both species with hybrids in an intermediate position, demonstrating the hybridization of these species in Caatinga. Nuclear DNA and metabolite diversity supported the separation of the two species into three clusters, with a subdivision of C. pyramidale in populations from the north (Pernambuco) and south (Bahia). Metabolomics revealed a fourth group formed mostly by hybrids. Later generation hybrids were detected as intermediate morphological forms, and gene flow was assumed as asymmetric among species and populations, being higher from C. pyramidale to C. microphyllum in populations from Bahia State. Ecological data indicated niche overlap. Hence, interspecific gene flow occurs among Cenostigma tree species, contributing to the evolution of the dry forest. Given the karyotypic and genomic similarity among species, as well as molecular and ecological evidence, we infer that the hybrids are fertile, allowing introgression and contributing to systematic complexity in Cenostigma. Hybridization did not significantly increase chemodiversity in terms of novel compounds but differentiated hybrids from parental species. In summary, we highlight the importance of multiple evidence, particularly genetic, morphological, and metabolomic traits, in the identification of hybrids and its evolutionary impact in natural environments., (© 2024 Wiley‐VCH GmbH. Published by John Wiley & Sons Ltd.)

Habitat loss can lead to biotic homogenization (decrease in β diversity) or differentiation (increase in β diversity) of biological communities. However, it is unclear which of these ecological processes predominates in human-modified landscapes. We used data on vertebrates, invertebrates, and plants to quantify β diversity based on species occurrence and abundance among communities in 1367 landscapes with varying amounts of habitat (<30%, 30-60%, or >60% of forest cover) throughout the Brazilian Atlantic Forest. Decreases in habitat amount below 30% led to increased compositional similarity of vertebrate and invertebrate communities, which may indicate a process of biotic homogenization throughout the Brazilian Atlantic Forest. No pattern was detected in plant communities. We found that habitat loss was associated with a deterministic increase in faunal community similarity, which is consistent with a selected subset of species being capable of thriving in human-modified landscapes. The lack of pattern found in plants was consistent with known variation between taxa in community responses to habitat amount. Brazilian legislation requiring the preservation of 20% of Atlantic Forest native vegetation may be insufficient to prevent the biotic homogenization of faunal communities. Our results highlight the importance of preserving large amounts of habitat, providing source areas for the recolonization of deforested landscapes, and avoiding large-scale impacts of homogenization of the Brazilian Atlantic Forest., (© 2024 Society for Conservation Biology.)

Fire is a major disturbance affecting ecosystems globally, but its impact on mutualisms has received minimal attention. Here, we use a long-term field experiment to investigate the impact of different fire regimes on globally important ant-honeydew and ant-extrafloral nectar (EFN) mutualistic interactions in an Australian tropical savanna. These interactions provide ants with a key energy source, while their plant and hemipteran hosts receive protection services. We examined ant interactions on species of Eucalyptus (lacking EFNs) and Acacia (with EFNs) in three replicate plots each of burning every 2 and 3 years early in the dry season, burning late in the dry season every 2 years, and unburnt for > 25 years. The proportions of plants with ant-honeydew interactions in Acacia (44.6%) and Eucalyptus (36.3%) were double those of Acacia plants with ant-EFN interactions (18.9%). The most common ants, representing 85% of all interactions, were behaviourally dominant species of Oecophylla, Iridomyrmex and Papyrius. Fire promoted the incidence of ant interactions, especially those involving EFNs on Acacia, which occurred on only 3% of plants in unburnt plots compared with 24% in frequently burnt plots. Fire also promoted the relative incidence of behaviourally dominant ants, which are considered the highest quality mutualists. Contrary to expectations, frequent fire did not result in a switching of behaviourally dominant ant partners from forest-adapted Oecophylla to arid-adapted Iridomyrmex. Our findings that frequent fire increases ant interactions mediated by honeydew and extrafloral nectar, and promotes the quality of ant mutualists, have important implications for protective services provided by ants in highly fire-prone ecosystems., (© 2024. The Author(s).)

Chronic anthropogenic disturbance (CAD) and climate change represent two of the major threats to biodiversity globally, but their combined effects are not well understood. Here we investigate the individual and interactive effects of increasing CAD and decreasing rainfall on the composition and taxonomic (TD), functional (FD) and phylogenetic diversity (PD) of plants possessing extrafloral nectaries (EFNs) in semi-arid Brazilian Caatinga. EFNs attract ants that protect plants against insect herbivore attack and are extremely prevalent in the Caatinga flora. EFN-bearing plants were censused along gradients of disturbance and rainfall in Catimbau National Park in north-eastern Brazil. We recorded a total of 2243 individuals belonging to 21 species. Taxonomic and functional composition varied along the rainfall gradient, but not along the disturbance gradient. There was a significant interaction between increasing disturbance and decreasing rainfall, with CAD leading to decreased TD, FD and PD in the most arid areas, and to increased TD, FD and PD in the wettest areas. We found a strong phylogenetic signal in the EFN traits we analysed, which explains the strong matching between patterns of FD and PD along the environmental gradients. The interactive effects of disturbance and rainfall revealed by our study indicate that the decreased rainfall forecast for Caatinga under climate change will increase the sensitivity of EFN-bearing plants to anthropogenic disturbance. This has important implications for the availability of a key food resource, which would likely have cascading effects on higher trophic levels., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Under continuous human disturbance, regeneration is the basis for biodiversity persistence and ecosystem service provision. In tropical dry forests, edaphic ecosystem engineering by biological soil crusts (biocrusts) could impact regeneration by influencing erosion control and soil water and nutrient fluxes, which impact landscape hydrology, geomorphology, and ecosystem functioning. This study investigated the effect of cyanobacteria-dominated biocrusts on water infiltration and aggregate stability in a human-modified landscape of the Caatinga dry forest (NE Brazil), a system characterized by high levels of forest degradation and increasing aridity. By trapping dust and swelling of cyanobacterial filaments, biocrusts can seal soil surfaces and slow down infiltration, which potentially induces erosion. To quantify hydraulic properties and erosion control, we used minidisc-infiltrometry, raindrop-simulation, and wet sieving at two sites with contrasting disturbance levels: an active cashew plantation and an abandoned field experiencing forest regeneration, both characterized by sandy soils. Under disturbance, biocrusts had a stronger negative impact on infiltration (reduction by 42% vs. 37% during regeneration), although biocrusts under regenerating conditions had the lowest absolute sorptivity (0.042 ± 0.02 cm s -1/2 ) and unsaturated hydraulic conductivity (0.0015 ± 0.0008 cm s -1 ), with a doubled water repellency. Biocrusts provided high soil aggregate stability although stability increased considerably with progression of biocrust succession (raindrop simulation disturbed: 0.19 ± 0.22 J vs. regenerating: 0.54 ± 0.22 J). The formation of stable aggregates by early successional biocrusts on sandy soils suggests protection of dry forest soils even on the worst land use/soil degradation scenario with a high soil erosion risk. Our results confirm that biocrusts covering bare interspaces between vascular plants in human-modified landscapes play an important role in surface water availability and erosion control. Biocrusts have the potential to reduce land degradation, but their associated ecosystem services like erosion protection, can be impaired by disturbance. Considering an average biocrust coverage of 8.1% of the Caatinga landscapes, further research should aim to quantify the contribution of biocrusts to forest recovery to fully understand the role they play in the functioning of this poorly explored ecosystem., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Szyja, Felde, Lückel, Tabarelli, Leal, Büdel and Wirth.)

Ants, an ecologically successful and numerically dominant group of animals, play key ecological roles as soil engineers, predators, nutrient recyclers, and regulators of plant growth and reproduction in most terrestrial ecosystems. Further, ants are widely used as bioindicators of the ecological impact of land use. We gathered information of ant species in the Atlantic Forest of South America. The ATLANTIC ANTS data set, which is part of the ATLANTIC SERIES data papers, is a compilation of ant records from collections (18,713 records), unpublished data (29,651 records), and published sources (106,910 records; 1,059 references), including papers, theses, dissertations, and book chapters published from 1886 to 2020. In total, the data set contains 153,818 ant records from 7,636 study locations in the Atlantic Forest, representing 10 subfamilies, 99 genera, 1,114 ant species identified with updated taxonomic certainty, and 2,235 morphospecies codes. Our data set reflects the heterogeneity in ant records, which include ants sampled at the beginning of the taxonomic history of myrmecology (the 19th and 20th centuries) and more recent ant surveys designed to address specific questions in ecology and biology. The data set can be used by researchers to develop strategies to deal with different macroecological and region-wide questions, focusing on assemblages, species occurrences, and distribution patterns. Furthermore, the data can be used to assess the consequences of changes in land use in the Atlantic Forest on different ecological processes. No copyright restrictions apply to the use of this data set, but we request that authors cite this data paper when using these data in publications or teaching events., (© 2021 The Authors. Ecology © 2021 The Ecological Society of America.)

Mutualisms may be more or less sensitive to environmental conditions depending on the diversity and responses of the species involved. Ants frequently form mutualistic associations with plants bearing extrafloral nectaries (EFNs): the ants protect the plants from herbivores and receive food resources (i.e., nectar) in return. As ectotherms, ants are strongly influenced by temperature, and temperature shifts can affect ant-plant interactions in ways that often depend on species functional traits. In this study, we explored the influence of EFN size and leaf surface temperature on ant-plant interactions in a Caatinga dry forest in Brazil. We observed the ants visiting 14 EFN-bearing plant species at different times of day over 12 sampling months; we also measured leaf surface temperatures during these periods. We next quantified EFN size for 68 individuals from the 14 plant species. The observational data were used to characterize the heat tolerance of the attendant ant species (i.e., based on levels of foraging activity). We then evaluated the mutualism's degree of functional resilience using two indices: functional redundancy (i.e., the number of ant species interacting with a given plant species) and thermal response diversity (i.e., variability in the heat tolerance of the ant species interacting with a given plant species). We found that leaf surface temperature, but not EFN size, had an influence on mutualism functional resilience. As temperatures increased, both functional redundancy and thermal response diversity decreased. This result implies that warmer global temperatures could heighten the vulnerability of facultative ant-plant mutualisms, regardless of plant traits., Competing Interests: Declarations. Conflict of interest: The authors declare that there is no conflict of interest/competing interests. This study does not contain any experiments using animal species that require ethical approval., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

For the development of efficient management and conservation strategies for wild rodent species, understanding the aspects related to their reproduction, including the interaction of this physiological function with the environment, is essential. This study aimed to evaluate the impacts of weather changes derived from a semiarid region's dry and rainy seasons on the epididymal sperm characteristics of red-rumped agouti (Dasyprocta leporina), a histricognath rodent, still little studied, which inhabits the Brazilian Caatinga. The sperm from the epididymal cauda of 14 agoutis were collected, seven individuals per season (dry and rainy). Samples were evaluated for kinetic parameters, membrane structural and functional integrity, mitochondrial activity, morphology, and morphometry. The environmental variables were measured: maximum air temperature, relative humidity, wind speed, solar radiation, and the total rainfall for dry and rainy seasons were, respectively, 36.2 and 34.1 °C, 66.8 and 80.1%, 4.0 and 1.9 m/s, 527.3 and 441.8 W/m 2 , and 0.2 and 517.7 mm. There were strong correlations between some sperm parameters and environmental variables, mainly those related to the acquisition of sperm mobility. Sperm concentration and the number of sperm collected were higher in the dry (1028.7 sperm/mL × 10⁶ and 1361.2 × 10 6 sperm) than in the rainy season (758.9 sperm × 10⁶/mL and 714.6 sperm × 10 6 ). During the rainy season, there were fewer sperm defects, higher sperm metrics, and higher membrane structural integrity with mitochondrial activity. Regarding motility patterns, the increases during the rainy season stand out in total and progressive motility, VAP, VSL, VCL, and subpopulations of rapid sperm. In summary, our results suggest that the adverse climatic conditions of the dry season in the semiarid region, mainly high solar radiation and temperature, considerably impair the epididymal sperm quality of red-rumped agoutis. On the contrary, the largest amount of sperm was obtained during this season, probably due to compensatory and adaptive mechanisms of the species to enable its reproduction throughout the year., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

High Andean butterflies in northern South America are subject to landscape change processes. Our study used models to assess the habitat suitability of three Satyrinae species in the Upper Bogotá River Basin, Colombia. These three species include Pedaliodes polla (Thieme), Pedaliodes phaea (Hewitson), and Pedaliodes phaeina (Staudinger), the last two are endemic to Colombia. We used MaxEnt software to assess the habitat quality of these species, analyze the bioclimatic requirements that most influence them, and propose priority conservation areas. Our results indicated that, in most cases, the contribution of cover is more significant than 60%, so this variable determines the habitat capacity to support the species under study. We identified that the areas with suitable habitats are reduced with values less than or equal to 25% and are located in areas with a medium degree of intervention, which allows the species to occur. On the other hand, the climatic variables with the most significant contribution to the models were Temperature Seasonality and Precipitation of Driest Quarter (May-July). Conservation efforts must be focused on the most suitable areas, given the reduction in habitat for these species. Our research emphasizes the need to safeguard well-connected remnants of the high Andean forest and natural cover in agricultural matrices to counter the impact of agricultural expansion., (© 2024. Sociedade Entomológica do Brasil.)

Interest in forest regeneration has increased as secondary forests in regeneration process are cited as the forests of the future. However, remaining forests are subjected to chronic anthropogenic disturbances, which may reorganize tropical biodiversity. This paper investigates the recovery of fruit-feeding butterfly assemblages following slash-and-burn agriculture in the Caatinga dry forest, assessing the roles that chronic disturbances, tree species richness and biomass play in their taxonomic and functional recovery during secondary succession. Butterflies were recorded monthly across old-growth forest stands and areas previously subjected to slash-and-burn agriculture, and with differing times since abandonment. While there was a high degree of similarity in community-level attributes among regenerating forests of different ages, secondary and old-growth forests supported relatively distinct assemblages, both taxonomically and functionally. As expected, chronic disturbance, forest biomass and trees species richness were excellent predictors of taxonomic and functional changes. Specifically, large-bodied and canopy-inhabiting butterflies reached higher abundances in more disturbed habitats, while those ocellus-bearing species that fly in the understory and feed on monocot as larvae responded negatively to disturbance, but benefited from increased forest biomass and tree species richness. Our findings suggest that although regenerating secondary forests can recover values of community-level attributes of fruit-feeding butterflies similar to those of old-growth forests, chronic anthropogenic disturbances across the landscape may be selecting only specific ecological groups that are tolerant to adverse conditions. Implications for insect conservation: Chronic disturbance can taxonomically and functionally alter butterfly assemblages across forest regeneration and consequently impact their ecological functions. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the mineral profile and histopathological findings in the liver of Leptodactylus macrosternum (white-lipped frog) and to assess the association between melanomacrophage areas and hepatic fungal granuloma with several factors such as weight, snout-cloacal length, sex, hepatosomatic index, season (dry and rainy), and condition factor K. A total of 135 frogs of different ages were collected from three areas in the city of Petrolina, Pernambuco, with varying land use (conventional agriculture, organic agriculture, and Caatinga stricto sensu). The liver of all specimens exhibited changes such as granulomatous lesions, inflammatory cell infiltrate, blood vessel congestion, and sinusoid dilation. The melanomacrophage areas were influenced by weight, snout-cloacal length, and hepatosomatic index. Our findings revealed a positive correlation between body size (weight and snout-cloacal length) and melanomacrophage/hepatic granuloma, while the hepatosomatic index showed a negative relationship. For the condition factor K, only age presents relationship. Eleven elements were quantified for the mineral profile, with aluminum (Al), iron (Fe), and zinc (Zn) being the most abundant in both liver and muscle. Although the histopathological findings and mineral profile of the liver and muscle in this study indicate an effect on the health of L. macrosternum in different collection areas, confirming the relationship between environmental characteristics and these findings requires future studies. Furthermore, long-term studies would be necessary to allow the monitoring of all stages of development of these populations, from tadpoles to adults, for a better evaluation of these effects in L. macrosternum., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction: Prosopis juliflora (Sw.) DC. substantially threatens dry rangelands due to its invasive attributes, exacerbated by climate change, land-use practices, and anthropogenic activities. Despite the urgent need to understand its ecological impacts, comprehensive studies examining the relationship between its functional traits and reproductive fitness across diverse habitats and land-use scenarios are lacking. This study investigated the functional traits and fitness of Prosopis juliflora in the Afar region of Ethiopia, focusing on three land-use types: dry-season grazing lands, wet-season grazing lands, and wildlife reserves. Methods: Plant samples were collected from 192 plots to assess their adaptive potential and genetic variation, alongside relevant physiographic and climatic data. This approach aims to elucidate the contributions of these factors to the observed variation and plasticity of Prosopis juliflora across three rangeland types differing in land use intensity. Generalized linear mixed models and co-occurrence networks were employed to analyze the complex interaction. Results: Our findings revealed significant variation in fruiting onset and duration, with wet-season grazing lands demonstrating a shorter duration compared to dry-season grazing lands and wildlife reserves. Genetic variation was significant for total seed mass and number, indicating robust adaptability. The relative growth rate was higher in wildlife reserves compared to dry-season grazing lands, highlighting adaptive advantages in nutrient-rich environments. Additionally, climatic and physiographic analysis identified soil type as a critical factor influencing trait performance. Conclusions: This study underscores the urgent need for targeted management strategies to mitigate the ecological impacts of Prosopis juliflora, emphasizing the critical role of soil nutrients in reproductive fitness. Our findings offer valuable insights into the dynamics of invasive species in dry ecosystems and inform conservation efforts. [ABSTRACT FROM AUTHOR]

The study was conducted to characterize the physicochemical properties of honey produced from underground nesting stingless bees (Meliponula beccarii) in the Dandi and Meta Robi districts of the West Shewa zone, Ethiopia. A total of 27 honey samples, including 24 samples collected through careful investigation and excavation of natural nests and 3 samples purchased from the market, were analyzed in the laboratory. The evaluated physicochemical properties showed an overall mean of 306.64±87.95 meq./kg free acidity, 28.05±3.52% moisture content, 1.31±0.44 mS/cm electrical conductivity, 3.29±0.16 pH, 0.89±1.14 mg/kg HMF, 0.63±0.24% mineral (ash), 9.39±4.26% glucose, 0.24±0.01 g/100g sucrose, 10.81±4.95 g/100g maltose, and 16.57±2.55 g/100g fructose, turanose (0.20 ± 0.00 g/100g). The differences between the two district's honey samples were significant (p > 0.05) for fructose value and considerable for free acidity, moisture content, and pH values. The honey samples purchased from the market showed similar physicochemical properties to the honey from the feral nests, with a mean of 314.33±88.72 meq./kg free acidity, 27.73±2.52% moisture content, 1.43±0.41 mS/cm electrical conductivity, 3.26±0.13 pH, 0.95±1.23 mg/kg HMF, 0.59±0.19% mineral (ash), 10.11±4.11% glucose, 0.25±0.02 g/100g sucrose, 11.23±4.52 g/100g maltose, and 16.33±2.41 g/100g fructose. The study found that the stingless bee honey from the study areas had distinctive low HMF, high free acidity, and low pH values, which may indicate the honey's potential medicinal properties. The high free acidity in the Meliponula beccarii honey appear unusually elevated compared to other stingless bee honey and the Codex Alimentarius standards for Apis honey, suggesting increased fermentation that can originate from the bee species, plant and geographical origins, improper handling, and high moisture content. This study demonstrated that the honey in the study areas has distinctive physicochemical properties from A. mellifera-produced honey, which may support its traditional medicinal uses. Further detailed studies on ground-nesting and other stingless species' honey medicinal values are recommended to provide scientific evidence. [ABSTRACT FROM AUTHOR]

The family Agaricaceae is one of the most diverse and species-rich families within the phylum Basidiomycota with a variety of fruiting body morphologies (agaricoid, secotioid, and gasteroid), ecological roles (e.g., saprotrophs and ant mutualists), and products of economic value (e.g., as food and medicine). The latest classification based on morphology and molecular data recognized around 59 genera within this family. The classification of Agaricaceae has, however, changed through time and is still in continuous review. Here, we used a multilocus approach sequencing the markers ITS, LSU, RPB2, and TEF1 for most of the type species of genera traditionally included in the Agaricaceae using taxa from Tricholomataceae and Lyophyllaceae as outgroups. Based on our taxon-dense phylogenetic analyses, we propose Agaricaceae to be divided into tribes following and expanding on Singer's (1986) classification: Agariceae, Coprineae, Cystolepioteae, Leucocoprineae, Lepioteae, Lycoperdeae, Macrolepioteae, and Tulostomateae. Furthermore, we conclude that the family Lycoperdaceae should be included within Agaricaceae and that Nidulariaceae should remain a separate family outside Agaricaceae. This is the first study of this family including agaricoid as well as secotioid and gasteroid species representatives, confirming their position within Agaricaceae. Our results further clarify the classification of this important mushroom family supporting previous morphological work as well as novel relationships. Nevertheless, the classification of various species within the genera Agaricus, Leucoagaricus, Leucocoprinus, Macrolepiota, and Morganella remain unresolved, and we suggest further studies may be needed with more data (genome-level phylogenies) as well as relevant species to resolve pending relationships within those particular genera. [ABSTRACT FROM AUTHOR]

Meristematic fungi are mainly defined as having aggregates of thick-walled, melanised cells enlarging and reproducing by isodiametric division. Dothideomycetes black meristematic and meristematic-like fungi have been allied to Myriangiales, which currently has two accepted families, Myriangiaceae and Elsinoaceae, with fungi mainly regarded as pathogens, parasites, saprobes and epiphytes of different plant species. This study aimed to verify the phylogenetic position using four nuclear markers (SSU, LSU, ITS and RPB2) of the incertae sedis genera associated with Myriangiales, namely Endosporium, Gobabebomyces, Lembosiniella and Phaeosclera, and the new genus, Endophytium gen. nov. (including E. albocacti sp. nov. and E. cacti sp. nov.), established for endophytic fungi occurring in cacti in Brazil. Based on morphology, lifestyle and phylogenetic inferences, these black meristematic and meristematic-like fungi cannot be accommodated in Myriangiales. Combining these results, three new orders and two new families are introduced: Endophytiales ord. nov. (including Endophytiaceae fam. nov. for Endophytium gen. nov.), Endosporiales ord. nov. (including Endosporiaceae for Endosporium) and Phaeosclerales ord. nov. (including Phaeoscleraceae fam. nov. for Phaeosclera). Gobabebomyces and Lembosiniella remained incertae sedis due to their disposition in the phylogenetic tree, that moved among clades accordingly with the gene analysed. Our results show that the inclusion of endophytic fungi obtained from plants in dry forests can contribute to the discovery of new taxa, clarify the phylogenetic position of allied taxa and confer information to the estimation of national and global fungal diversity. [ABSTRACT FROM AUTHOR]

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Species in dry environments may adjust their anatomical and physiological behaviors by adopting safer or more efficient strategies. Thus, species distributed across a water availability gradient may possess different phenotypes depending on the specific environmental conditions to which they are subjected. Leaf and vascular tissues are plastic and may vary strongly in response to environmental changes affecting an individual's survival and species distribution. To identify whether and how legumes leaves vary across a water availability gradient in a seasonally dry tropical forest, we quantified leaf construction costs and performed an anatomical study on the leaves of seven legume species. We evaluated seven species, which were divided into three categories of rainfall preference: wet species, which are more abundant in wetter areas; indifferent species, which are more abundant and occur indistinctly under both rainfall conditions; and dry species, which are more abundant in dryer areas. We observed two different patterns based on rainfall preference categories. Contrary to our expectations, wet and indifferent species changed traits in the sense of security when occupying lower rainfall areas, whereas dry species changed some traits when more water was available, such as increasing cuticle and spongy parenchyma thickness, or producing smaller and more numerous stomata. Trischidium molle, the most plastic and wet species, exhibited a similar strategy to the dry species. Our results corroborate the risks to vegetation under future climate change scenarios as stressed species and populations may not endure even more severe conditions., (© 2023. The Author(s) under exclusive licence to The Botanical Society of Japan.)

Several barriers contribute to reproductive isolation between plant species, which can be classified as pre- or post-pollination. Understanding the strength of these barriers could clarify the factors that maintain reproductive isolation and thus species integrity. In this study, we quantified reproductive isolation between two bat-pollinated co-occurring Bauhinia species (B. acuruana and B. pentandra) with similar flower morphology. Over the course of 18 months, we assessed reproductive isolation between these two Bauhinia species by quantifying the individual strengths and absolute contributions of five pre- and post- pollination barriers. Our data showed that both species are completely isolated in their reproduction by a combination of several barriers. Although they co-occur in a few populations, we found a high degree of geographic isolation between them. And although their flowering periods overlap, there is a significant difference in flowering peaks. Both species have the same pollinating bats, but the interspecific transfer of pollen between the plant species may be reduced due to the different length of the flower stamens, resulting in different pollen deposition on the bats' bodies. We have documented complete incompatibility between taxa and conclude that pre- and post-pollination barriers are important factors in preventing gene flow, even in contact zones between these two species of Bauhinia. We highlight that our work is the first study to use methods to estimate the strength of reproductive isolation barriers between bat-pollinated species., (© 2023. The Author(s) under exclusive licence to The Botanical Society of Japan.)

Ecological interactions in tropical ecosystems are being modified by chronic anthropogenic disturbances (CAD) and climate change. Pollination is a key mutualistic interaction that can be affected by disturbance and climate change due to alterations in the composition, diversity, and distribution of plants, floral resources, and pollinators. We tested if increasing CAD and aridity induces changes in pollen traits and female reproductive success of Tacinga palmadora, a self-compatible cactus that performs as an important food source for nectar-feeding and fruit-eating animals, in the Caatinga dry forest. The study was carried out in eight plots at the Catimbau National Park, northeastern Brazil. Each plot had a different level of disturbance and aridity, used as predictor variables against pollen traits (total pollen production, pollen viability, and pollen-ovule ratio) and female reproductive success (fruit- and seed-set by both open and spontaneous self-pollination) in generalized linear models. All pollen traits were negatively associated with increasing CAD and aridity intensity, while the seed- and fruit-set by open pollination were positively associated with increasing CAD and aridity, respectively. Spontaneous self-pollination was not influenced by increasing CAD and aridity. Our results revealed that even though pollen traits decrease with higher CAD and aridity, pollination of T. palmadora is maintained or even increased in the most arid and disturbed areas of the park. We conclude that, in terms of pollination effectiveness, T. palmadora might be thriving under disturbances and aridity in the Caatinga dry forest. [ABSTRACT FROM AUTHOR]

Myracrodruon urundeuva, popularly known as 'aroeira-do-sertão', a large tree, with a tall trunk. Belonging to the Anacardiaceae family, it occurs in the 'caatinga' and dry forests of Brazil, from Ceará to the states of Paraná and Mato Grosso do Sul. The present study aimed to analyse the whitening and antioxidant activities of the aqueous extract of the leaves of Myracrodruon urundeuva (AELMU). Inhibition of the tyrosinase enzyme, as well as its copper chelating capacity and antioxidant effect were evaluated. The AELMU (at 2000 µg/mL) showed excellent inhibitory action (83.76%) on tyrosinase by chelating the copper ion while kojic acid at the same concentration inhibited 97.81%. Moreover, the extract displayed important antioxidant activity (inhibited 76,46% of the 2,2-diphenyl-1-picrylhydrazyl radical - DPPH; 49,59% of thiobarbituric acid reactive substances and 51,07% of the hydroxyl radical). Thus, the extract under study is promising for use in cosmetics, given its multifactorial action. [ABSTRACT FROM AUTHOR]

Background: Synchronopatric plant species, coexisting and flowering simultaneously, often engage in intense competition for pollen deposition on shared pollinators. This study focuses on the intricate dynamics of chiropterophilous flowers within the neotropical bat-pollination plant guild, specifically investigating the mechanical fit of reproductive structures to pollinating bats at the community level. Methods: Utilizing a diverse guild of bat-pollinated plant species from the Caatinga, the largest dry forest in the Neotropics, our research integrates various key components. Initially, we identified specific contact sites for floral reproductive structures on the bat's body, exploring diverse pollen placement strategies. Subsequent efforts involved characterizing floral traits within the guild and examining their associations with different pollen placement strategies. Precision in the contact of floral reproductive structures was estimated, and findings were integrated by associating pollen placement strategies and precision with the investment in pollen production. Results: We found that certain bat body parts, particularly the face and neck, were more frequently contacted by reproductive structures. The three identified categories of pollen placement strategies were evenly distributed among plant species, each linked to specific floral traits. Notably, the absence of oriented herkogamy prevailed in 70% of the species. Morphometric analyses unveiled significant variations in operative distances among species, emphasizing exceptional variability in certain outliers. While precision in pollen transfer was influenced by key factors, surprisingly, investment in pollen production did not differ among plants with distinct pollen placement strategies. Furthermore, it showed no correlation with fundamental accuracy. Conclusions: The subsequent exploration delves into the intricate associations between distinct floral characteristics and various pollen placement strategies, shaping the complex pollen landscape on bat bodies. This research provides valuable insights into the community-level dynamics of chiropterophilous flowers in the Caatinga Dry Forest, emphasizing the role of different pollen deposition strategies in facilitating the coexistence of multiple plant species within the chiropterophilous guild. [ABSTRACT FROM AUTHOR]

Bats are unique among mammals in their capacity for powered flight and present high species diversity and feeding habits in the Neotropical region. Despite the remarkable increase in knowledge on the distribution of neotropical bats in recent decades, information on the species' occurrence throughout Brazil is still widely heterogeneous, with significant knowledge gaps in many biomes. The Ubajara National Park (PNU), northwestern Ceará, is an area of extreme biodiversity in the Caatinga biome, characterized by several natural caves associated with a noticeable bat community. Herein, we carried out a complementary inventory of bat diversity in the PNU, focusing on six caves and their surrounding foraging sites. Two surveys totaling 36 sampling nights were conducted using complementary methods such as mist nets, harp trap, roosting searches, and acoustic monitoring. Thirty species of bats belonging to eight families were recorded. We found significant complementarity between the sampling methods resulting in the stabilization of the rarefaction curve. Eight species were found in roosting colonies in at least one of the sampled cavities. A total of 965 individuals from 18 species, with the majority belonging to the family Phyllostomidae, were recorded using active sampling techniques. Passive acoustic monitoring yielded 14 different sonotypes of species from the Emballonuridae, Mormoopidae, Molossidae, Vespertilionidae, and Noctilionidae families. The acoustic activity of bats from distinct families was higher in the dry season and varied throughout the night. Two species registered with passive acoustic monitoring were among the captured ones, thus reinforcing the importance of diversifying methodologies to obtain more complete bat inventories. [ABSTRACT FROM AUTHOR]

The connection between plant species and nest site preference for the Asian weaver ant Oecophylla smaragdina remains poorly understood despite their common occurrence in the urban areas of tropical regions. We predicted that plant species with specific leaf characteristics influence the nesting preference of Asian weaver ants, given that plant foliage is the main component of their nest structure. We studied the leaf characteristics of the tree species in which their nests were detected, including leaf shape, leaf apex shape, and leaf arrangement. Of the 206 total trees among the 20 tree species sampled, 185 trees from 18 tree species had at least one nest. Trees of the genus Lagerstroemia had the highest median nest abundance, whereas all Roystonea regia and Caryota no trees, and some Samanea saman trees, were not occupied by O. smaragdina. For the trees found to have O. smaragdina nests, the nest abundance in each tree ranged between 1 and 16 nests, with the majority having fewer than 10 nests per tree (4.38 ± 4.45). Based on nest abundance, the oblong and elliptic leaf shapes (LS), the cuspidate leaf apex shape (LX), and the opposite leaf arrangement (LR) were the most used for nest construction, consisting of more than 50% of the total in each respective category. A Kruskal-Wallis test revealed that O. smaragdina nest site preference is influenced by LX and LR but not by LS. Additionally, O. smaragdina nest abundance was negatively correlated to leaf surface ratio but insignificant for leaf surface area. These preferred qualitative and quantitative leaf characteristics determine the species of plants used as nesting sites to facilitate nest-building efficiency and the establishment of Asian weaver ant colonies. [ABSTRACT FROM AUTHOR]

Background: Zoology's dark matter comprises hyperdiverse, poorly known taxa that are numerically dominant but largely unstudied, even in temperate regions where charismatic taxa are well understood. Dark taxa are everywhere, but high diversity, abundance, and small size have historically stymied their study. We demonstrate how entomological dark matter can be elucidated using high-throughput DNA barcoding ("megabarcoding"). We reveal the high abundance and diversity of scuttle flies (Diptera: Phoridae) in Sweden using 31,800 specimens from 37 sites across four seasonal periods. We investigate the number of scuttle fly species in Sweden and the environmental factors driving community changes across time and space. Results: Swedish scuttle fly diversity is much higher than previously known, with 549 putative specie) detected, compared to 374 previously recorded species. Hierarchical Modelling of Species Communities reveals that scuttle fly communities are highly structured by latitude and strongly driven by climatic factors. Large dissimilarities between sites and seasons are driven by turnover rather than nestedness. Climate change is predicted to significantly affect the 47% of species that show significant responses to mean annual temperature. Results were robust regardless of whether haplotype diversity or species-proxies were used as response variables. Additionally, species-level models of common taxa adequately predict overall species richness. Conclusions: Understanding the bulk of the diversity around us is imperative during an era of biodiversity change. We show that dark insect taxa can be efficiently characterised and surveyed with megabarcoding. Undersampling of rare taxa and choice of operational taxonomic units do not alter the main ecological inferences, making it an opportune time to tackle zoology's dark matter. [ABSTRACT FROM AUTHOR]

Palm swamp forests are wetland ecosystems typical of the Brazilian Cerrado, which in recent decades have undergone intense changes due to land use alterations and climate change. As a result of these disturbances, many palm swamps have been experiencing significant drying, which can also affect adjacent vegetation. In the present study, we evaluated whether the drying of palm swamps affects the structure of plant–herbivore networks located in adjacent savanna areas in Brazil. Our results show that savanna areas adjacent to dry zones of palm swamps have fewer interactions, fewer interacting species, and a less specialized topology, which corroborates our expectations. Our findings indicate that the drying of palm swamps also has propagated impacts on adjacent savanna vegetation, impairing more specialized interactions in these environments. On the other hand, contrary to expectations, plant–herbivore networks in dry zones displayed higher modularity, lower nestedness and lower robustness than those in wet zones, suggesting that in dry environments, species tend to compartmentalize their interactions, even with lower interaction specialization. This is the first study to investigate the impacts of environmental drying on the structure of plant–herbivore networks in tropical ecosystems, highlighting the complexity of these effects and their differential impact on specialized and generalized interactions. Understanding these dynamics is crucial for developing effective conservation and management strategies in the face of ongoing environmental changes. [ABSTRACT FROM AUTHOR]

Understanding the ecological relationship between fungi and insects is essential for elucidating interactions in biodiverse regions such as South American biomes. This study aimed to evaluate the influence of biome, host species, and microhabitat on the community structure of yeasts (using culture-dependent methods) and fungi (culture-independent methods) in bees and to identify the functional characteristics of isolated strains. Samples were collected from the body, hive, honey, and beebread of bees from the genera Trigona, Scaptotrigona, Tetragona, Apis, Meliponas, and Tetragonisca in the Pantanal, Amazon, and Cerrado biomes. We isolated 176 strains representing 46 yeast species, predominantly from the genera Starmerella (44.32%), Hanseniaspora (5.16%), and Wickerhamiella (4.38%). Starmerella etchellsii (32%) was the most abundant species, while Aureobasidium leucospermi (< 0.01%) was the least abundant. Only S. etchellsii and S. apicola (11%) were present in all bee species. The composition and abundance of yeasts were significantly influenced by biome and host species (PERMANOVA, p < 0.05). Alpha diversity varied significantly among microhabitats (Dunn's p < 0.05), bee species, and biomes (Duncan p < 0.05). Culture-independent methods identified 234 Ascomycota ASVs, 18 Basidiomycota ASVs, and 1 Mucoromycete ASV across 90 genera and 108 species. Saccharomycetales accounted for approximately 72% of the fungal abundance, with S. apicola (14.64%) and S. meliponinorum (11.21%) being the most abundant. Additionally, barcoding identified 100 ASVs of plants associated with bees, grouped into 22 families and 24 species, predominantly Asteraceae, Anacardiacea, Elaeocarpaceae, and Solanaceae. The functional characteristics of the yeasts showed potential for industrial applications, varying according to the strain. [ABSTRACT FROM AUTHOR]

Due to agriculture and logging, Costa Rica has lost many primary forests, making reforestation an important task. To judge the progress of reforestation, it is important to follow the reassembly of organismal communities within restored habitats. The COBIGA project near La Gamba, in the Golfo Dulce region of Costa Rica, aims at reforestation of lowland sites with native tree species. Ants, as ubiquitous and highly abundant terrestrial organisms, have a substantial influence on tropical ecosystems. The multiple roles include scavenging, predation, herbivory, and mutualistic interactions. We examined ant community responses to reveal the status of community regeneration and functional integrity. We compared the composition and diversity of the ant assemblages at three different age reforestation sites (2, 8, and 10 years old) with those at an old-growth forest as a reference site. By offering canned tuna fish at ground level along replicated transects, we observed 43 ant species representing six functional groups during the 2 months of sampling. Most of the observed ant species were omnivorous, but old-growth forests harbored a substantial number of other functional groups, such as generalized predators, arboreal predators, and arboreal omnivores. In contrast, the youngest reforestation site harbored a severely impoverished ant assemblage comprising mostly generalized polygynous and polydomous ant species from lower trophic levels. The within-site heterogeneity of the ant assemblages increased from the youngest to the oldest forest. In addition, our results show the importance of monitoring the progress of forest recovery to avoid the spread of invasive species into primary habitats. [ABSTRACT FROM AUTHOR]

Rivers interlinking by transposition projects have multiplied in the world, altering the landscape and flow regime of continental water systems. Recently, an intermittent river in northeastern Brazil has been artificially connected to the São Francisco River basin in a water transfer project. Thus, this study aims to provide an inventory of the fish parasites from the Jaguaribe River basin in the scenarios of pre- and post-transposition, and to evaluate the short-term impacts on the parasite fauna. Of the analyzed fishes, belonging to 31 species, about 30% were parasitized. A total of 47 parasite taxa were recovered, including monogeneans (17), digeneans (9), nematodes (9), acanthocephalans (3) and crustaceans (6), and unidentified cysts of Acanthocephala, Cestoda and Digenea, representing the description of 30 new geographic records and 104 new parasite-host associations. By expanding the range of the geographic distribution of fish parasites and increasing the list of hosts, the study contributes to the knowledge of fish parasites biodiversity in the semi-arid region of Brazil and in the Caatinga domain. Considering all parasite species, significant differences were observed in total prevalence, total mean abundance, diversity index and host specificity index; the highest values of total prevalence and total mean abundance were observed in the post-transposition, while the diversity index and host specificity index was higher in the pre-transposition period. This is the first study evaluating fish parasites before and after a major water transfer event and the results will allow further evaluation of middle and long-term changes in the specific composition of fish and parasites from the receiver drainages. [ABSTRACT FROM AUTHOR]

Background: The interplay between different uses of woody plants remains underexplored, obscuring our understanding of how a plant's value for one purpose might shield it from other, more harmful uses. This study examines the protection hypothesis by determining if food uses can protect woody plants (trees and shrubs) from wood uses. We approached the hypothesis from two distinct possibilities: (1) the protective effect is proportional to the intensity of a species' use for food purposes, and (2) the protective effect only targets key species for food purposes. Methods: The research was conducted in a rural community within "Restinga" vegetation in Northeast Brazil. To identify important food species for both consumption and income (key species) and the collection areas where they naturally occur, we conducted participatory workshops. We then carried out a floristic survey in these areas to identify woody species that coexist with the key species. Voucher specimens were used to create a field herbarium, which, along with photographs served as visual stimuli during the checklist interviews. The interviewees used a five-point Likert scale to evaluate the species in terms of perceived wood quality, perceived availability, and use for food and wood purposes. To test our hypothesis, we used Cumulative Link Mixed Models (CLMMs), with the wood use as the response variable, food use, perceived availability and perceived quality as the explanatory variables and the interviewee as a random effect. We performed the same model replacing food use for key species food use (a binary variable that had value 1 when the information concerned a key species with actual food use, and value 0 when the information did not concern a key species or concerned a key species that was not used for food purposes). Results: Consistent with our hypothesis, we identified a protective effect of food use on wood use. However, this effect is not directly proportional to the species' food use, but is confined to plants with considerable domestic food importance. Perceived availability and quality emerged as notable predictors for wood uses. Conclusion: We advocate for biocultural conservation strategies that enhance the food value of plants for their safeguarding, coupled with measures for non-edible woody species under higher use-pressure. [ABSTRACT FROM AUTHOR]

Seasonally Dry Tropical Forests (SDTFs) have long suffered from chronic, intensive and extensive landscape transformations due to human activities, challenging biodiversity conservation in this biome. The Caatinga is the largest Neotropical SDTF, serving as an excellent model to understand how land use changes modulate ecological communities. In this study, we assessed the effects of landscape configuration and composition on the abundance and diversity of Chrysomeloidea in a region of Caatinga. We sampled beetles in 10 landscape units, in which we measured landscape configuration (patch size, edge density) and composition (landscape diversity, patch richness). Hill numbers (q0, q1, q2) were used to analyze the diversities of Chrysomeloidea. A total of 484 individuals belonging to 82 species were collected. Landscape configuration affected Chrysomeloidea assemblages with a positive correlation between edge density and Chrysomeloidea diversity. We provide a new perspective regarding the spatial distribution of Chrysomeloidea in Caatinga and conclude that landscape configuration, but not composition, directly affects Chrysomeloidea assemblages. [ABSTRACT FROM AUTHOR]

Background: Sicariidae is a small family of cryptic and recluse spiders, with 178 species grouped into three genera: Hexophtalma, Loxosceles and Sicarius. Only the last two occur in Brazil, where 29 species are recorded, with a greater number of records in the Southeast and South regions. To date, there is no regionalized study of the distribution of these spiders in the Northeast of Brazil. We presented more than four decades of data on the distribution of sicariid spiders in the state of Bahia. Our research aimed to identify and evaluate the distribution of sicariid species in this region, characterizing them in their biomes and phytophysiognomies. Methods: Data covers a period from 1983 to 2024, obtained from articles describing species recorded in Bahia and from three scientific collections from Brazilian institutions: Universidade Federal da Bahia (MHNBA); Instituto Butantan (IBSP); Universidade Federal de Minas Gerais (UFMG). Maps were produced using the QGIS 3.34.1 software, based on geographic coordinates obtained from the original literature, when provided. Species without information on geographic coordinates were georeferenced using the SpeciesLink (geoLoc tool) for the municipalities. Biomes were consulted on the georeference Brazilian institute website and the phytophysiognomies were ignored when not specified in the data of collections or original literature. Results: We confirmed 14 species of sicariid spiders in the state of Bahia, eight from the genus Loxosceles (i) and six from Sicarius. The species were recorded in 48 municipalities, located mainly in the Caatinga biome. We recorded a distribution expansion of seven species: Loxosceles amazonica, L. chapadensis, L. karstica, L. similis, Sicarius cariri, S. ornatus and S. tropicus. There is a difference in species composition in the two regions separated by the São Francisco River, an important geographic barrier especially for small invertebrates. More than 75% of the species were registered in the east side and about 20% exclusively in the west side: L. boqueirao, L. cardosoi, L. carinhanha. This suggests the need for future studies to evaluate additional variables that determine community structure, especially considering their low vagility and reclusive behavior. Although Sicarius are found almost exclusively in the Caatinga, there are isolated records from Restinga and dry forest enclaves in the Cerrado domain and Atlantic Forest areas. This reinforces the possibility of them being able to adapt to slightly wetter environments erase colonize and survive in seasonally dry rainforest areas. Unlike Sicarius (i), Loxosceles (i) occupy a wide variety of habitats in natural, urban and domiciliary situations. Many of the records here such as for Loxosceles boqueirao, L. cardosoi, L. carinhanha, L. chapadensis, L. karstica and L. troglobia were obtained at caves or nearby areas, which appear to be attractive habitats for these nocturnal spiders. [ABSTRACT FROM AUTHOR]

Aim: Plant herbivory and disease, which are often associated with each other but subject to different processes, are pivotal in biodiversity maintenance and ecosystem function. Although drivers of plant herbivory and disease have been widely studied separately, their relationships, patterns and determinants remain unclear in fragmented landscapes. Methods: We surveyed incidence and severity of foliar herbivory and disease of 2,027 adult trees within 30 sites in 17 tropical forest fragments in Xishuangbanna, southwestern China. We aim to explore the relationship of plant herbivory and disease, and effects of local environmental variables (forest type, plant richness, elevation, slope, soil properties) and landscape environmental variables (patch size, edge distance, isolation). Results: We found that incidence, but not severity of disease was positively correlated with that of herbivory. Herbivory severity and incidence were more associated with local variables; both increased with plant richness but decreased with soil nutrients and pH. In contrast, the landscape variable isolation was the dominant driver of disease, with lower severity and incidence in contiguous forests than forest fragments. Conclusion: In summary, we show that herbivory and disease are associated with drivers at different scales in fragmented landscapes. Herbivory is mainly driven by local-scale variables, while disease is mainly driven by landscape-scale variables. To control plant herbivory and disease in fragmented landscapes, increasing landscape connectivity and conserving different forest types are urgently required to maintain ecosystem functions under global land use change. [ABSTRACT FROM AUTHOR]

Habitat fragmentation and ecosystem changes have the potential to affect animal populations in different ways. To effectively monitor these changes, biomonitoring tools have been developed and applied to detect changes in population structure and/or individual traits that reflect such changes. Fluctuating asymmetry (FA) represents random deviations from perfect symmetry in bilateral traits from perfect symmetry in response to genetic and/or environmental stresses. In this study, we evaluated the use of FA as a tool to monitor stress caused by forest fragmentation and edge formation, using the tropical butterfly M. helenor (Nymphalidae) as a model species. We collected adult butterflies from three fragments of Atlantic Forest in Brazil encompassing both edge and interior habitats. Four wing traits (wing length, wing width, ocelli area, and ocelli diameter) were evaluated. Butterflies captured at edge sites exhibited higher FA values for wing length and wing width compared to those captured at interior sites, whereas traits related to ocelli did not show differences between the two habitat types. Our results suggest that the differences in abiotic and biotic conditions between forest interior and edges can act as a source of stress, impacting the symmetry of flight-related traits. On the other hand, as ocelli are crucial for butterfly camouflage and counter-predator strategies, our results indicate that this trait may be more conserved. By employing FA, we identified trait-specific responses to habitat fragmentation, thus suggesting its potential as a biomarker for environmental stress that can be used in butterflies to monitor habitat quality and change., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Fauna inventories reduce biodiversity knowledge gaps by providing comprehensive data on species distribution, richness, and abundance. Furthermore, they identify undocumented species and enhance understanding of ecosystem dynamics and conservation needs. The richness and abundance of amphibian species were studied in two Semideciduous Seasonal Forest areas in the municipalities of Potiraguá (Serra Azul) and Itarantim (Serra do Mandim) in southwestern Bahia, Brazil. Active visual and acoustic surveys were conducted in 24 forest interior transects, two stream transects, and two permanent ponds investigated in the study area. Opportunistic encounters during team movements were also recorded. The richness was 46 amphibian species distributed in 14 families and 26 genera. Approximately half of the species were shared between the two areas, while 11 species were exclusive to Serra Azul and another nine were found only in Serra do Mandim. Cluster analysis for 42 locations in Atlantic Forest, Caatinga, and Cerrado, in a presence/absence matrix with 216 species, revealed that the composition of the amphibians found in Serra do Mandim and Serra Azul is similar to other sampled locations in the northeastern region of Minas Gerais, close to the study site, which are considered transitional between the Atlantic Forest and the Caatinga. Our results demonstrate that the remaining forest fragments in the region, although small and isolated, still sustain a high richness of amphibians with species restricted to the Atlantic Forest and Bahia, such as Bahius bilineatus, Ololygon strigilata, Aplastodiscus weygoldti and Vitreorana eurygnatha, and others considered typical of the Caatinga, such as Leptodactylus troglodytes and Physalaemus cicada. Additionally, we sampled potential new species, filled occurrence gaps, and expanded the geographical range of Pseudis fusca. [ABSTRACT FROM AUTHOR]

The Brazilian Amazon has undergone an intense process of urbanization responsible for changes in the land use and land cover patterns in the last decades. Therefore, understanding the impacts resulting from the urbanization of Amazon become urgent, both to preserve biodiversity and associated ecosystem functions and services, since Amazon region comprise a key ecosystem regarding biodiversity and ecological dynamics. We studied, for the first time, the impact of urbanization on dung beetles, a recognized bioindicator group, in an Amazonian landscape. For this, we assessed the dung beetle taxonomic and functional responses along a preserved-rural-urban habitat gradient in an Amazonian city, and how landscape predictors affect dung beetle diversity. We found a consistent shift in species composition and reduction of both taxonomic and functional diversity from forest patches located outside the city towards those located in the city core. In addition, forest cover was the main driver of dung beetle responses at the landscape scale, where the increase of forest cover positively affected dung beetle diversity. Our results provide evidence that urbanization negatively impacts the dung beetle taxonomic and functional diversity in Amazonian cities, and reinforce the importance of maintaining forest cover to conserve dung beetles in tropical forests. Finally, the development of sustainable initiatives for the conservation of biodiversity in urban landscapes, such as public policies aimed at the maintenance of urban forest fragments, can help to maintain biodiversity and ecosystem processes within cities and to mitigate the urbanization impacts. [ABSTRACT FROM AUTHOR]

Numerous studies have examined the effect of invasive species on biodiversity in urban environments, however, few of them have investigated the role of native species while turning into invasive pests. In Colombia, Atta cephalotes, a native leaf-cutting ant (LCA), has responded successfully to the conversion of natural ecosystems to agricultural-rural environments and, most recently, to residential and urban development. In this study, we illustrate the incidence and distribution of this native ant species in an environment where animal life must face urban disturbs in the physical environment, resource availability, and ecosystem processes associated with human urbanization in Cali, the third most important city in Colombia. For this, A. cephalotes nests were georeferenced in public green areas located in 12 communes across the city of Cali, southern Colombia. Vegetation and soil cover, urban settings, foraging trails and plants foraged by the ants were recorded. A. cephalotes nests were present in all green areas and, even in human dwellings; the ants harvested both native and introduced plant species. Despite being well adapted to strongly modified urban environments, this ant species appears to be dependent on human-subsidized resources. Given the wide distribution of leaf-cutting ants in Latin America, it is plausible to expect that similar processes are underway in other countries where these ants are found. Hence, this study also proposes to alert the academic and social communities to direct future research towards evaluating both the responses and impacts of these ants in relation to changes in the urban landscape. [ABSTRACT FROM AUTHOR]

Seed dispersal by ants plays a major role globally in plant dynamics for many angiosperms and can be influenced by multiple factors. One of those factors is competition between ants and other organisms for gaining access to seeds. A habitat with high abundance of potential competitors for ants is forests in marine coast ecosystem, where there is a high abundance of terrestrial crabs that functionally act as seed predators. In a coastal forest on Coiba Island, Panama, we measured seed removal rates at increasing intervals from the coast towards the interior of the forest, representing a decreasing gradient in ant–crab competition. We found that seed removal was dominated by hermit crabs near the coast, and while ants moved more seeds as the distance from the coast increased. We expect that this differential removal should generate varying levels of seed predation and seedling establishment, with crabs acting mainly as seed and seedling predators. This study provides insights into how ant–crab dynamics may play a role in maintaining the vegetation gradients in coastal ecosystems. [ABSTRACT FROM AUTHOR]

Social insects demonstrate two fundamentally different modes of reproduction, independent colony foundation (ICF) by single fertilized queens or dependent colony foundation (DCF) by fissioning of existing colonies into two or several new colonies (swarms). In some species, both reproductive modes occur in parallel. The benefits and disadvantages of DCF vs. ICF have been widely discussed and been subject to empirical studies, but a formal theoretical treatment of the topic is still incomplete. Taking honey bees as example, we provide a resource allocation model of colony dynamics to analyze the ecological conditions under which DCF may be favored over ICF. Using mathematical and numerical methods, we show that it critically depends on the survivorship function linking swarm size to the probability of swarm establishment whether ICF or DCF results in a higher output of surviving new colonies. Because building larger swarms requires larger inter-swarm time intervals, DCF can only be a better strategy if this disadvantage is over-compensated for by a strong size-dependent swarm survivorship and survival of single queens is very low. Colony growth rate has no effect on this decision and the impact of maximum possible colony size is negligible. Further, there is a discontinuity in the optimal swarm size, so that either a swarm size of 1 (ICF) is the best strategy, or emitting swarms of considerable size (DCF). Consequently, a direct evolutionary transition from ICF to DCF appears unlikely and may have been triggered by selective pressures promoting movement of complete nests or distributing single colonies over several nests (polydomy). [ABSTRACT FROM AUTHOR]

The response of soil microorganisms and plants in soil ecosystems to biochar is well recognised. However, biochars' impact on large soil animal, such as ants, is inadequately understood, with only limited studies focusing on the abundance and mortality rates of some specific ant species. In this study, soil physicochemical properties, and ant community diversity and functional characteristics were compared between experimental plots with and without biochar application. No significant differences in soil (soil physicochemical properties) or ants (ant community richness, species abundance, and morphological characteristics) were observed between the two plots before biochar application. However, the biochar-treated plot soil surface temperatures, pH, and soil water content were significantly higher after 48 weeks. Biochar application promoted Cardiocondyla nuda (by 426%) and Formica japonica abundance (by 93%), but decreased Solenopsis invicta invasive ant species richness (by 54%), consistent with the fact that changes in soil properties were more beneficial to the former two species. In addition, in biochar-treated plots, F. japonica and S. invicta generally showed larger body size (18% and 6.7%), larger eyes (2.7% and 4.0%), and longer femurs (6.3% and 7.9%), which enabled them to respond better to potential barriers, such as plants. Our results highlighted that, besides species abundance and community structure, certain ant functional morphological indicators were also informative in evaluating biochar ecological implications. Highlights: Biochar application enhanced soil temperature, pH, and water content. Ants showed larger body size, larger eyes, and longer femurs with biochar application. Biochar promoted ant richness by creating ant-preferred habitats. [ABSTRACT FROM AUTHOR]

Leaf-cutting ants are the most important pests in several cropping systems in the Neotropics. Granulated baits containing active ingredients, considered hazardous by the Stockholm Convention, are the usual method to control these ants. Isocycloseram is a new insecticide molecule with high safety margin for mammals, but without registration for the ants in general. Thus, this study investigated the effectiveness of granulated baits with isocycloseram in leaf-cutting ants control under laboratory and field conditions. Initially, the mortality of Atta sexdens workers, fed with dehydrated citrus pulp paste containing different concentrations of isocycloseram was evaluated in the laboratory for 21 days, for toxicological classification. Subsequently, the loading, devolution, and incorporation of baits with different concentrations of isocycloseram and the mortality of A. sexdens colonies were evaluated in the laboratory. After that, the percentages of loading and devolution of baits, foraging activity, and colony mortality treated with 0.05, 0.1, 0.2, and 0.3% of isocycloseram were evaluated for the species A. sexdens, A. laevigata, and Acromyrmex lundii in field conditions. All concentrations of isocycloseram killed more than 15% of ants in 24 h and more than 90% in 21 days in the laboratory, being classified as a fast-acting and highly effective active ingredient. Baits with 0.001 to 0.03% of isocycloseram were highly loaded and exhibited low rate of devolution. The mortality of A. sexdens colony was higher at concentrations between 0.075 and 0.3%, in the laboratory. Baits containing isocycloseram at concentrations of 0.2 and 0.3% were highly loaded, presented low devolution rates, and were highly efficient in controlling A. sexdens, A. laevigata, and A. lundii in the field, at dosages of 6, 10, and 12 g/m² of nest. This is the first report of the use of isocycloseram against leaf-cutting ants, contributing to the development of efficient and toxicologically safer ant baits. [ABSTRACT FROM AUTHOR]

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