In the present work, the reproductive ecology of nesting and the conservation history of the species of Podocnemis expansa were studied in a floodplain area called Ilha do Meio, in the lower Amazon River, West of Pará – Brazil. This island environment can be considered atypical for nesting, among others, because it is located on the bed of the Amazon River, a highly navigable region with intense movement of vessels, which suffers natural erosion, natural and anthropogenic predation. The site was monitored between October 2021 and January 2022, covering the stages of nesting, incubation and hatching/emergence of chicks. The nests were deposited in an area with fine grain size, at an average distance of 52.3 cm from the vegetation, an average final depth of 28 cm (±5.72 N=30) and an average of 97 eggs. Turtle mortality has been recorded due to burial, boat propeller accidents and exhaustion from physical exertion combined with excessive heat. The nests established in the nesting area were 100% flooded due to the low terrain and early onset of rain. This is the first work evaluating reproductive aspects of P. expansa on Ilha do Meio and may be the initial step towards understanding the existence and permanence of the chelonian population in this study area. The information presented here is part of the conservation protocol for the species P. expansa at the Ilha do Meio breeding site, which is published.

The general objective of the dissertation was to evaluate the beta diversity of Odonata adults based on the contribution of species (SCBD) and sites (LCBD). In addition to analyzing which environmental predictors are responsible for the variation of species composition. We collected biotic and abiotic variables in 117 streams in the eastern region of the Brazilian Amazon. All analyzes were performed separately for the order (Odonata) and for the suborders (Anisoptera/Zygoptera). We collected 4,187 individuals distributed in 156 species. Fifty-three sites had a high contribution to Odonata diversity. Forty-two sites contributed above average to Anisoptera diversity and fifty-four sites to Zygoptera. Forty species contributed above average to the diversity of Odonata. Since the Zygoptera species presented a greater contribution to the diversity than the Anisoptera species. The Odonata community was not influenced by any of the environmental variables analyzed. However, Anisoptera diversity was determined by dissolved oxygen and habitat integrity (HII). E of Zygoptera was determined by depth, water temperature, pH and HII. Our results suggest that there was a substitution of sensitive species for species tolerant to environmental changes, due to the suborders having presented opposite responses to the gradient of habitat integrity. The integrity of the habitat is closely related to the structure of the Odonata community, especially that of the suborders. From this relationship, it is possible to generate predictions about the processes that structure and maintain the community.

The capacity of species to adapt to different environmental gradients is essential for their survival, since the environment can present variations over space and time. These variations create different ecological niches, offering opportunities for different species to occur and remain in certain places, since the potential to withstand these conditions is related to the existence of adaptable attributes necessary for survival. Thus, our study sought to understand the relationship between an environmental variation gradient and the functional structure of adult Odonata assemblages in riparian zones of the Cerrado. Data were collected from 50 streams in eastern Maranhão and western Piauí, between May 2021 and January 2022. Five functional attributes were considered: total length, thorax width, abdomen length, forewing length and width, and environmental variables: canopy cover, channel width and depth. A total of 1.528 specimens of adult Odonata distributed in seven families, 30 genera and 74 species were collected. We found that more open areas or those with loss of vegetation had larger insects, with the cover of riparian vegetation adjacent to the channel being the main predictor of the structure of Odonata assemblages. As the size of organisms increases, their dependence on the sun's rays for heating also increases. Added to this, the selective pressure exerted by the environment drives the evolution and adaptation of wing shape in species. Thus, the selection of insects with specific characteristics is observed to the detriment of other groups according to the characteristics of the habitat. Additionally, this filtering can lead to the homogenization of biodiversity and loss of functionality in extreme or degraded environments, indicating that functional traits are relevant attributes for understanding the distribution of Odonata species, and that the conservation and proper management of riparian zones are indispensable to guarantee the survival of these species and of the different behavioral and ecophysiological groups that the order presents.

Observing and understanding how plant communities are assembled over a wide geographic space, taking into account a highly heterogeneous environment, which has been shown to be an extremely important factor in the origin and maintenance of ecological and evolutionary processes, will provide valuable information how to operate the assembly processes of communities. In this sense, we raise the following question: how do the local edaphic, climatic and hydrological gradients of the soil influence the patterns of the phylogenetic structure of the communities of the Zingiberales order throughout the entire Amazon region? For this, we downloaded occurrence data for Zingiberales throughout the entire Amazon region from the Global Biodiversity Information Facility (GBIF) and calculated the phylogenetic diversity metrics: Standardized effect size (SES) of mean pairwise distances (SES.MPD), mean nearest taxon distances (SES.MNTD) and Phylogenetic Diversity. And then we analyze the influence of edaphic, climatic and hydrological soil gradients on the patterns of the phylogenetic structure of the communities from the analysis of linear models. Thus, we observed that soil and climate affect the diversity and phylogenetic structure of communities. There are communities with higher SES.PD in regions where the soils are sandier and have a lower concentration of nitrogen and where the climate has less annual precipitation. We also observed an increase in phylogenetic grouping in regions with higher average annual temperature and more acidic soils (SES.MPD), and in regions with less sandy and clayey soils (SES.MNTD). The local hydrology condition did not significantly influence the phylogenetic relationships of plants in their communities. Therefore, we conclude that edaphic gradients strongly influence the diversity and phylogenetic structure of Zingiberales communities, both on a shallower (SES.PD) and deeper (SES.MPD) evolutionary time scale. Further reinforcing the importance of edaphic heterogeneity, which drives the distribution of floristic patterns in the Amazon region. In addition, we also emphasize the fact that our study covered a continental spatial scale and, probably thanks to this fact, we were able to identify the influence of the climate gradient on the phylogenetic structure of Amazonian herbaceous communities.

Environmental variables are important for structuring dung-beetle assemblages in mature native forests the Neotropics at the local scale. However, their relative importance in the context of land-use changes with crops of exotic forest species (i.e., eucalyptus) close to native forests is still not clear. In this study we argue: [i] how are dung-beetles assemblages influenced by environmental variables (i.e., soil texture, litter biomass, canopy opening), and distance to eucalyptus plantations? and [ii] which are the most important variables for structuring dung-beetles species composition? In order to assess such issues, we used GLMs, multivariate multiple regression and hierarchical partitioning analysis. The rarefied species richness of beetle has decreased with the increase of canopy opening and the percentage of sand in the soil. However, the distance to eucalyptus plantation alone and not soil texture or canopy opening, has significantly affected beetle abundance. Understanding the results of this study is important in a context of expansion of exotic tree plantations, which has been spreading through several Amazonian regions in the last decades, thus influencing the native fauna within native preserved forests nearby.

This study investigated the influence of the flood gradient on the variation of functional attributes in vegetative organs of Ischnosiphon puberulus for its establishment in the Amazonian riparian zone. The species was collected in the field and in a plant nursery to evaluate the effect of flooding and its suppression. The leaves, roots, and rhizomes were subjected to the usual methods of plant anatomy to quantify the variation in the functional attributes and their response to the flood gradient. In the field samples, the stomatal density on the abaxial surface of leaves had a positive relationship with waterlogging. In the roots, despite the presence of aerenchyma under any flooding conditions in the field, the individuals showed higher proportions of aerenchyma under more intense flooding conditions. With cultivation in the plant nursery, these proportions tended to decrease, or were absent. In the field, the cortex-to-pith ratio was higher in the individuals from more flooded plots than in less flooded areas, unlike the individuals in the plant nursery. Histochemical tests showed the presence of phenolic compounds in all the vegetative organs, as well as the starch in the leaves and rhizomes. The stomatal density of the abaxial surface of leaves and the aerenchyma-to-cortex ratio are the main functional attributes related to the most flooded plots. The leaf and rhizome functional attributes of plants subjected to flooding and its suppression did not vary between the field and plant nursery conditions. In the roots, the proportion of aerenchyma was the functional attribute with the highest plasticity, showing a positive correlation with field flooding and a negative correlation with its suppression in the nursery. This set of features allows I. puberulus to establish and spread along the entire flooding gradient, with the aerenchyma standing out as the most striking feature in response to flooding.

Climate change accelerated by human actions puts the survival of many living beings at risk. Thus, understanding how such changes can alter the geographic distribution of environmentally suitable areas for species that are notably susceptible to extinction in the future is essential to mitigate the negative effects of climate change on biodiversity. In this study, we investigated how climate change may influence the survival of two species of harlequin frogs, Atelopus hoogmoedi and Atelopus manauensis in the Brazilian Amazon, and which environmental factors contribute to the distribution of these species. In addition, we investigated whether there is a niche overlap between the studied species. We used 115 occurrence records of A. hoogmoedi and 37 records of A. manauensis and a set of climatic, edaphic, and topographical variables to project the areas potentially suitable for each species in different future climates scenarios. We considered the present climate and two climate change scenarios for the year 2070. In the most optimistic scenario, the projections showed a loss of suitable areas of 85.02% for A. hoogmoedi and 100% for A. manauensis, and in the most pessimistic one, a loss of 95.55% and 100% for A. hoogmoedi and A. manauensis, respectively. The potential losses of Areas of Environmental Suitability indicate that the survival of harlequin toads in Brazil is
under threat. The current environmental niche similarity of the species was slight, and the variables that most explain the distribution are related to temperature. Measures for conserving these species include preserving areas that harbor populations in the present and areas that indicate suitability in the future. For A. manauensis, considering the lack of future environmental suitability if the climatic scenarios materialize, only measures that stop climate change can increase the species' chances of survival.

Sustainable Use Protected Areas (SU-PAs) are a subgroup of PAs in Brazil that allows both the conservation of biodiversity and the sustainable exploration of natural resources, which are regulated by Management Plans that create zones to avoiding conflicts of interest. SU-PAs are key to maintaining biodiversity for their big size, and offer a great opportunity for conserving medium and large-bodied mammals (e.g., armadillos, large rodents, ungulates, large carnivores), especially in the Amazon. However, SU-PAs are usually affected both by internal and external pressures, and different parts of the same SU-PA may present distinct conservation values. We sampled mammals using camera traps in areas with distinct histories of human occupation in the Tapajós National Forest (TNF), and show differences in species richness, assemblage structure, number of records per species, and levels of defaunation and conservation. Although we cannot infer a causal effect, a compilation of other studies conducted in similar sites of the TNF suggest that human activities may have driven populations of some large-bodied mammal species such as the tapir and white-lipped peccary to very low levels. Local differences in human occupation uses within the same SU-PA are common in the Amazon, especially those with an extensive area, which demands specific actions from public authorities to minimize impacts on wildlife caused by both legal and illegal activities.

Gerromorpha (Insecta: Hemiptera: Heteroptera) comprises semiaquatic, - predatory stink bugs, that inhabit both lentic and lotic environments, usually gliding or walking on water or aquatic plants. Worldwide, more than 2100 species are described, of which 236 are registered in Brazil, with 126 of these species occurring in the North and 85 species in Pará state. These numbers, for Brazil, and especially for the North region and Pará, demonstrate that the knowledge about the diversity and distribution of Gerromorpha is still insufficient, considering the enormous territorial extension of the region. In Pará, there are still areas in need of fauna surveys, such as the metropolitan region of Santarém, which, so far, does not have an inventory for several groups of aquatic insects, including Gerromorpha -, which has been losing natural resources through human activities. Our objective was to reduce the lack of knowledge (Wallacean and Linnean deficits) about this group, inventorying the Gerromorpha fauna of the metropolitan region of Santarém. For this, manual collections were carried out with the aid of aquatic nets in 33 aquatic ecosystems, covering streams, waterfalls, pools, phytotelmata and lakes, between the months of July 2019 and October 2020. As results, we presented a commented and illustrated list of Gerromorpha species occurring in the study area, new records, we expanded the geographic distribution areas of known species and, we described new species. 44 species of Gerromorpha were collected, three new species of the genus Microvelia Westwood, 1834: M. belterrensis sp. nov., M. hamadae sp. nov. and M. sousorum sp. nov.; two new records were made for Brazil: Microvelia aschnakiranae Makhan, 2014 and Rhagovelia graziae Galindo-Malagón, Morales & Moreira, 2021; two new records for Pará state: Microvelia longipes Uhler, 1894 and Paravelia dilatata Polhemus & Polhemus, 1984, and; 15 new records for the metropolitan region of Santarém: Brachymetra lata Shaw, 1933, B. shawi Hungerford & Matsuda, 1957, Tachygerris adamsoni (Drake, 1942), Microvelia pulchella Westwood, 1834, Rhagovelia brunae Magalhães & Moreira, 2016, R. evidis Bacon, 1948, R. jubata Bacon, 1948, Callivelia conata (Hungerford, 1929a), Oiovelia cunucunumana Drake & Maldonado- Capriles, 1952, Paravelia bullialata Polhemus & Polhemus, 1984, Stridulivelia alia (Drake, 1957), S. stridulata (Hungerford , 1929b), S. strigosa (Hungerford, 1929b), S. tersa (Drake & Harris, 1941b) and S. transversa (Hungerford, 1929b). These results expand the knowledge about Gerromorpha in Pará state by 16% and the knowledge for the metropolitan region of Santarém by 50%; and demonstrate the importance and the need for fauna and taxonomic studies for the real knowledge of our biodiversity, as they can subsidize ecological studies, among others, by naming and understanding the distribution of species.

The Phaegopterina moths includes approximately 750 species registered in Brazil, for the Cerrado 254 species are registered and for the Amazon 469. In the present study we present an inventory with an annotated list of Phaegopterina species and distribution recorded for Maranhão. The material examined comes from collections in 10 municipalities in Maranhão. After analyzing the material in this study, we have a list of 116 species of Phaegopterina, distributed in 56 genera for Maranhão, with 25 species being new records. Updating the number of Phaegopterina records for Maranhão, after this study, we totaled 116 Phaegopterina species recorded for the state. Ongoing inventory efforts for Arctinae in Maranhão will contribute to an increase and understanding of the diversity of Lepidoptera in the Cerrado and Amazon.

Investigating the effects of environmental gradients on assemblage spatial structure is relevant to understand mechanisms and processes affecting biodiversity. Environmental gradients may act as ecological filters limiting species occurrence and abundance, which generates non-random patterns of habitat occupancy. Environmental filtering-mediated biodiversity emerges from relationships between environmental gradients and estimates of α- and β-diversity. Such relationships have been widely demonstrated in frog assemblages occupying forests in Amazonia but are rarely assessed in non-forest ecosystems such as macrophyte banks in lakes. Macrophyte banks may vary spatially in terms of width, height, and species composition, in response to physicochemical parameters of water. Therefore, it is reasonable to expect spatially heterogeneous frog assemblages in response to variation in habitat vertical stratification and perch shape. In this study we sampled 50 plots covering 15 km2 of continuous macrophyte banks to test the effects of distance from the lake bank, water depth, macrophyte height and composition (proportions of morphotype occupancy), pH, dissolved oxygen and temperature on frog α-diversity and β-diversity estimates. We found 16 species, for which local distribution was not random but characterized by α-diversity positively affected by macrophyte height, and β-diversity affected by macrophyte height and composition, and water depth. Our results suggest environmental filtering as a major factor structuring frog assemblages even in relatively small and regionally rare ecosystems. These findings are highly relevant to ecology and conservation because they suggest that aquatic macrophyte banks should be considered as distinct biogeographic units from adjacent habitats.

Ferns and lycophytes are seedless plants of ancient origin. Its dispersion through spores occurs by the wind, which makes them possible to occur in several places. They are important environmental indicators, becoming a special group when it comes to conservation. The Lower Tapajós region, located in the western region of Pará state, in the Tapajós River basin, has a large diversity of ferns and lycophytes, but all this richness is under threat from constant human actions such as fires in Protected Areas and construction of dams in the Tapajós river . The objective of this work was to analyze collection gaps, sampling biases, richness distribution and assess if protected areas in the Lower Tapajós are contributing to the conservation of the flora using ferns and lycophytes as model group. For this, a database was built from information of each fern and lycophyte specimen collected in the region and deposited in scientific collections or available in published works. These records were verified for location accuracy and correctness and were georeferenced when necessary. The records were checked and identified using a dichotomous key. The relationship between sampling effort and species richness was evaluated as well as whether records were biased towards areas close to access routes (defined as roads or navigable rivers). A comparison of species composition was made between the study areas and sixteen other areas that have fern and lycophyte inventories in the Brazilian Amazon. Here we present the first checklist for the ferns of the Baixo Tapajós basin, as well as for the four Conservation Units that presented records of these plants. It was possible to identify the conservation status of the species as well as places that had collection gaps. The sampling bias was also verified from the access routes in rivers and roads and it was possible to verify a collection density restricted to areas with easy access and close to large municipalities. Because it is a target region of destructive actions and a study group so sensitive to environmental changes, the information obtained from the research is of paramount importance to aid in the conservation of the flora of the Lower Tapajós region. Obtaining this data from an herbarium collection further enhances the preciousness of these scientific collections, and how much it is capable of storing and recording the history of the flora of a given region. Based on this study on information about the distribution of these plants, it is possible for managers of protected areas to use this information to develop species protection policies, so as to minimize conflicts of devastation in forest areas caused by human action.

We conducted an inventory of the fern, lycophyte and non-palm monocotyledon ground-herbs of terra firme riparian forests in the lower Tapajós River basin of the Brazilian Amazon. Eight 1.5 x 250 m plots, totaling 0.3 hectares, were surveyed along the watersheds of the Cupari and Curuá-Una tributaries of the Tapajós River, Floresta Nacional do Tapajós, Para, Brazil. To characterize the ground-herb community, we calculated species richness, abundance and Fisher’s alpha for each plot. To analyze floristic dissimilarity, we calculated the Bray-Curtis distance. In total, we sampled 3,130 individuals, 58 species, 27 genera and 20 families of riparian ground- herbs. Marantaceae (14 spp) was the richest family and Poaceae the most abundant family (738 individuals). The fern Triplophyllum glabrum (Tectariaceae) was the most frequent species, observed in 87.5 % of plots. Plots that showed the highest values for richness and species diversity were located in the Cupari River basin. The ground-herb community composition observed in the riparian zone here resembles that of other non-riparian forested sites in the Amazon with the plant families Marantaceae, Pteridaceae and Poaceae generally being the most commonly represented in the Amazonian ground-herb stratum.

Amphibian diversity can be influenced by many factors and quantifying the variation in biodiversity over time or space is a challenge. Beta diversity estimates are very useful for this purpose, as they quantify differences in species composition, functional or phylogenetic traits among multiple communities located in distinct portions of geographic and environmental gradients. However, beta diversity results may vary according to the variables used, but all available methods tend towards the general objective of identifying ecological, biogeographic and evolutionary factors that affect the variation in the composition of biodiversity across environments. Here, we investigate the factors that affect biodiversity in South America. For that, we selected the Sphaenorhynchini tribe, because it seems to be an ideal representative because it occurs in very different plant formations in relation to climate and vegetation, and some species seem to have been historically isolated by biogeographic barriers, such as large rivers and the expansion of the Brazilian Cerrado. Our main objective was to quantify the effects of evolutionary (phylogenies), historical (rivers as barriers) and ecological (geographical distance, environmental gradients) processes that have affected beta diversity in South America. Our results indicate that both taxonomic and beta diversity Phylogenetics of Sphaenorhynchini revealed two distinct clusters, corresponding to the Amazon and Atlantic Forest. In the Amazon, the effects of phylogenetic diversity were stronger than in the Atlantic Forest, which demonstrates that evolutionary processes have played a greater role in determining regional communities. In the Atlantic Forest, environmental variation seems more important. In both biomes, beta diversity was affected by environmental gradients, while in Amazon precipitation was the most important variable, tree cover was more relevant in the Atlantic Forest.

The combination of techniques capable of discriminating plant species that are difficult to circumscribe is essential to the proper understanding of biodiversity. The genus Microgramma C.Presl (Polypodiaceae), for example, due to the great complexity of forms associated with the wide area of occurrence, becomes a group highly suggestive to the taxonomic investigation. Thus, we aim to propose processes of discrimination in species of neotropical ferns through integrative tools of great interest in the taxonomic field. We used near-infrared spectroscopy (FT-NIR) in thirteen species (M. baldwinii, M. crispata, M. dictyophylla, M. geminata, M. lindbergii, M. lycopodioides, M. megalophylla, M. percussa, M. persicariifolia, M. reptans, M. squamulosa, M. thurnii, and M. vacciniifolia) and
morphometric analysis with four species (M. crispata, M. geminata, M. mauritiana, and M. vacciniifolia). These are important methods for the discrimination of botanical species in association with multivariate analyzes, such as Discriminant Analysis, cross-validations, Canonical Discriminant Analysis (CDA), and Cluster Analysis (CA). Based on multivariate analyzes, the morphometric technique supported the existence of all previously recognized
taxa, as well as the Near-Infrared Spectroscopy (FT-NIR), with which we recovered more than 95% of correct prediction. Both applied techniques demonstrated a high potential for discrimination between the proposed species, demonstrating that the use of different approaches can favor greater reliability in the delimitation between controversial groups.

Recognition and delimitation of taxonomic categories of biological organisms are still challenging and full of controversies. Traditional categorization of species may hamper the continuous variation of entities in nature. The assessment of morphometric and spectral variation of individuals along geographical and environmental gradients can be used to understand how homogeneous or grouped is the variation and may underscore the delimitation of natural units. We used Ischnosiphon (Marantaceae) as a model to test these ideas due to its great morphological variation and broad distribution. Species of this genus are terrestrial rhizomatous herbs, occurring in the understories of tropical forests from Nicaragua to southern Bolivia and Brazil. Here we apply an individual-based approach to test how variation of 22 wide or narrowly distributed species of Ischnosiphon is related to ecological factors and geographical distribution, besides describing morphological and spectral variation patterns. We demonstrate great diversity and morphological complexity among Ischnosiphon, and proposed a replicable and analytical framework to accommodate individual variability in species diagnosis on morphologically diverse plant groups. Additionally, we show that range size is not a good predictor of phenotypic variance and that climatic distance is often more relevant to morphological and spectral variation than geographic distance. These results provide evidence of how our interpretation and recognition of species is prone to underestimation of the role of individual variability, and how environmental gradients influence phenotypic variation of widely distributed organisms. Finally, we discuss the relevance of phenotypic variability explorations on systematics, evolutionary and ecological studies.

Savannas in the Amazon are restricted to only about 3% of the Amazon basin, and knowledge about fish diversity in these areas is still incipient, which is the least studied group of organisms. Environmental changes generate changes in aquatic habitat, so changes in the fish community are expected over time, but when they do not profoundly affect water quality, some resistance from communities is expected. To determine the composition of the ichthyofauna, three samplings were performed in 13 first and second order streams inserted in forest fragments surrounded by a savannah matrix on the left bank of the lower Tapajós River. May and the last in October 2018. To investigate the effects on the change of environmental characteristics on the taxonomic composition of fish, a set of ten streams from the October 2006 and 2018 samplings were used. A standardized effort protocol was used. A total of 6,094 individuals were collected distributed in 43 species, belonging to 21 families and eight orders, Characiformes and Cichliformes being the most representative orders. The community composition of these streams is different from nearby areas, corresponding to an important set for regional diversity. The intensity and direction of the temporal change of the datasets between 2006 and 2018 were analyzed. Changes in some structural and limnological characteristics of the streams between the years were detected, showing a decrease in the environmental integrity. There was no change in the taxonomic composition of the community. Although fish are able to withstand the current level of environmental degradation on these streams, there are variations in the total abundance of some species-related changes in specific microhabitats, it is likely that changes in the use of streams that intensify the loss of water quality. may lead to diversity losses. Therefore, investigations are needed to quantify this kind of effect and monitor its changes.

Spatial variation in morphological traits emerges in response to different selective pressures experienced when geographic range crosses heterogeneous habitats. In seasonally flooded habitats, animal adaptation is conspicuously demonstrated by the ability to swim among tops of hills that form islands during flooding, or by the ability to climb treetops above the water level. We have noticed that a widely distributed terrestrial snake is forced to climb treetops in flooded várzea forests of eastern Amazonia. We hypothesized that seasonal flooding of habitats selects morphotypes by the levels of adaptation to use treetops as foraging and resting sites. We measured seven morphological variables on 30 Bothrops atrox specimens from floodable várzea forests, and 25 specimens from non-floodable terra firme forests. Models of Discriminant Analysis of Principal Components (DAPC) separately by sex showed morphological differences between these habitat types, which were independent of geographic distance. We found longer tail and wider head in females and lower head and slimmer body in males from the várzea forests sampled. Despite sex-biased divergences in selected morphological traits, our results converge to natural selection toward arboreality in seasonally flooded habitats. We ultimately show an intermediary stage of evolutionary divergence, although speciation is not clear as in island-isolated populations.