Metacommunity patterns of Amazonian Odonata: The role of environmental gradients and major rivers

Background. We identified and classified damselfly (Zygoptera) and dragonfly (Anisoptera) metacommunities in Brazilian Amazonia, relating species distribution patterns to known biological gradients and biogeographical history. We expected a random distribution of both Zygoptera and Anisoptera within interfluves. At the Amazonian scale, we expected Anisoptera metacommunities to be randomly distributed due to their higher dispersal ability and large environmental tolerance. In contrast, we expected Zygoptera communities to exhibit a Clementsian pattern, limited by the large Amazonia rivers due to their low dispersal ability. Methods. We used a dataset of 58 first-to-third order well-sampled streamlets in four Amazonian interfluves and applied an extension of the Elements of Metacommunity Structure (EMS) framework, in which we order Zygoptera and Anisoptera metacommunities by known spatial and biogeographic predictors. Results. At the Amazonian scale, both Zygoptera and Anisoptera presented a Clementsian pattern, driven by the same environmental and biogeographical predictors, namely biogeographic region (interfluve), annual mean temperature, habitat integrity and annual precipitation. At the interfluve scale, results were less consistent and only partially support our hypothesis. Zygoptera metacommunities at Guiana and Anisoptera metacommunities at Tapajós were classified as random, suggesting that neutral processes gain importance at smaller spatial scales. Discussion. Our findings were consistent with previous studies showing that environmental gradients and major rivers limit the distribution of Odonata communities, supporting that larger Amazonian rivers act as barriers for the dispersal of this group. In addition, the importance of habitat integrity indicates that intactness of riparian vegetation is an important filter shaping metacommunity structure of Amazonian stream Odonata.This work was supported by the Coordination for the Improvement of Higher Education Personnel—CAPES (120147/2016-01), Brazil National Council for Scientific and Technological Development—CNPq (303252/2013-8, 574008/2008-0, 305542/2010-9,478884/2008-7, 314523/2014-6), Brazilian Agriculture Research Corporation EMBRAPA (SEG 02.08.06.005.00), the UK Darwin Initiative (17023), The Nature Conservancy and the Natural Environment Research Council—NERC (NE/F01614X/1 and NE/G000816/1)

Changes of Phylogenetic and Taxonomic Diversity of Odonata (Insecta) in Response to Land Use in Amazonia

Changes in natural habitats for human use can alter the distribution of biodiversity, favoring species that are more tolerant to environmental disturbance. Usually, these species comprise clades of habitat generalists, which have biological mechanisms to colonize environments with different environmental conditions. However, such effects are still poorly understood for most biological groups, such as the Amazon odonates. Therefore, this study aims to evaluate the effects of land use along an environmental gradient on the phylogenetic and taxonomic diversity of Odonata in the Amazon. We tested the following hypotheses: In deforested areas (e.g., pasture for cattle, palm plantation, and logging), the Odonata community will be more taxonomically and phylogenetically impoverished than in forested areas. We assume that the modification of the natural habitat causes loss of specialist forest species and favors specialist species of open areas and/or habitat generalists. Data sampling was performed in 195 streams under different land-use types: livestock areas, palm monoculture, timber exploitation, and forest areas taken as reference sites. Our results showed that anthropogenic impacts affected the phylogenetic diversity of odonates and the increase in shrub vegetation was related to the increase in the phylogenetic diversity of communities. On the other hand, shrub vegetation is indicative of disturbed areas, where secondary vegetation predominates, with less canopy cover due to the absence or discontinuity of the native tree cover in these habitats. Nonetheless, species richness and abundance were not related to the effects of anthropogenic land use. Finally, our results suggest that the phylogenetic diversity of Amazonian odonates is related to riparian vegetation structure

EMERGENCE TRAP FOR THE COLLECTION OF EXUVIAE AND ADULT OF ODONATAs

Odonates have aquatic larval stages and terrestrial adults. The extreme change in habitat occupation during their life cycle means that combined collection methods, capable of providing data for both larvae and adults, are scarce and are often inefficient. Given this, we applied a method for the collection of specimens of both life phases using emergence traps. During fieldwork, 78 emergence events were recorded for 15 species. We also briefly discuss the emergence pattern of the recorded species. We believe the information obtained here provide an important contribution to the understanding of the ecology and basic biology of Neotropical odonate species, as well as helping to solve the taxonomic problems associated with the identification of larvae

In Neotropical savannas, altitude affects the diversity of the Anisoptera but not the Zygoptera (Insecta: Odonata)

Lentic and lotic habitats, combined with varying altitudes, may have differential effects on communities of the Order Odonata. We sampled adult odonates at 94 waterbodies of the Orinoquía region of eastern Colombia. Our hypothesis was that species composition and richness, as well as abundance, would be affected by both altitude and habitat. Overall, 70 of the 100 species recorded in the study were sampled in both lotic and lentic environments, with 16 species (5 in the Suborder Zygoptera and 11 in the Suborder Anisoptera) occurring only in lentic habitats and 14 occurring exclusively in lotic habitats (13 Zygoptera, 1 Anisoptera). The results of the analysis indicated that the species richness and abundance of anisopterans were affected by altitude, whereas the diversity of zygopterans was not affected in any way. Despite these mixed findings, the results for anisopterans were consistent with the results of previous studies, which have indicated altitude as a primary determinant of the Odonata diversity through its effect on the dynamics of water flow and the shift from lentic to more lotic environments. Further studies over a more ample altitudinal gradient should provide more conclusive evidence, particularly regarding the role played by both altitude and habitat on the local diversity of odonates

EMERGENCE TRAP FOR THE COLLECTION OF EXUVIAE AND ADULT OF ODONATAs

Odonates have aquatic larval stages and terrestrial adults. The extreme change in habitat occupation during their life cycle means that combined collection methods, capable of providing data for both larvae and adults, are scarce and are often inefficient. Given this, we applied a method for the collection of specimens of both life phases using emergence traps. During fieldwork, 78 emergence events were recorded for 15 species. We also briefly discuss the emergence pattern of the recorded species. We believe the information obtained here provide an important contribution to the understanding of the ecology and basic biology of Neotropical odonate species, as well as helping to solve the taxonomic problems associated with the identification of larvae

Prey availability and temporal partitioning modulate felid coexistence in Neotropical forests

Carnivores have long been used as model organisms to examine mechanisms that allow coexistence among ecologically similar species. Interactions between carnivores, including competition and predation, comprise important processes regulating local community structure and diversity. We use data from an intensive camera-trapping monitoring program across eight Neotropical forest sites to describe the patterns of spatiotemporal organization of a guild of five sympatric cat species: jaguar (Panthera onca), puma (Puma concolor), ocelot (Leopardus pardalis), jaguarundi (Herpailurus yagouaroundi) and margay (Leopardus wiedii). For the three largest cat species, we developed multi-stage occupancy models accounting for habitat characteristics (landscape complexity and prey availability) and models accounting for species interactions (occupancy estimates of potential competitor cat species). Patterns of habitat-use were best explained by prey availability, rather than habitat structure or species interactions, with no evidence of negative associations of jaguar on puma and ocelot occupancy or puma on ocelot occupancy. We further explore temporal activity patterns and overlap of all five felid species. We observed a moderate temporal overlap between jaguar, puma and ocelot, with differences in their activity peaks, whereas higher temporal partitioning was observed between jaguarundi and both ocelot and margay. Lastly, we conducted temporal overlap analysis and calculated species activity levels across study sites to explore if shifts in daily activity within species can be explained by varying levels of local competition pressure. Activity patterns of ocelots, jaguarundis and margays were similarly bimodal across sites, but pumas exhibited irregular activity patterns, most likely as a response to jaguar activity. Activity levels were similar among sites and observed differences were unrelated to competition or intraguild killing risk. Our study reveals apparent spatial and temporal partitioning for most of the species pairs analyzed, with prey abundance being more important than species interactions in governing the local occurrence and spatial distribution of Neotropical forest felids

Distribuição de Heteroptera Aquáticos (Insecta) em Diferentes Tipos de Substratos de Córregos do Cerrado Matogrossense

A comunidade de Heteroptera de córregos do cerrado do Leste Matogrossense foi analisada para determinar os tipos de substratos que contemplam a maior variação de composição de espécies. Foram realizadas coletas nos substratos de folhiço de corredeira e remanso, raiz, cascalho, pedra (matacão), areia e na superfície d’água (camada de tensão superficial) das nascentes, trechos médios e foz dos córregos Santo Antônio e Colher em dezembro/2004 e julho/2005, com cada substrato representado por seis subamostras. Foram coletados 333 indivíduos distribuídos em 11 famílias, 20 gêneros e 30 morfoespécies (17 Nepomorpha e 13 Gerromorpha), sendo os Gerromorpha mais abundantes (172 indivíduos). A riqueza estimada de Gerromorpha nos substratos foi superior em coletas na superfície d’água, enquanto Nepomorpha apresentou maior riqueza em raiz, seguido por cascalho e folhiço de corredeira. Os substratos inorgânicos (pedra e areia) apresentaram reduzida riqueza de Heteroptera. Entre os Gerromorpha, Limnogonus aduncus aduncus Drake & Harris, Rhagovelia elegans Uhler, Neogerris lubricus White e Brachymetra sp.1 foram associados com coletas de superfície e Stridulivelia anta Polhemus & Spangler com substrato raiz. Em Nepomorpha, Martarega chinai Hynes foi associado com coletas de superfície, enquanto que Ambrysus sp. 1 mostrou associação ao folhiço de corredeira, de remanso, raiz e superfície. Com esses resultados ressaltamos que trabalhos que visem levantamentos rápidos da comunidade de Heteroptera devem priorizar coletas de superfície para Gerromorpha e de raiz para Nepomorpha, pois esses substratos abrigam as maiores riquezas de cada infraordem, contemplando 83% e 64% da riqueza de espécie desses grupos respectivamente. Distribution of Aquatic Heteroptera (Insecta) From Different Types of Streams Substrate of Cerrado in Mato Grosso Abstract. The Heteroptera community of Cerrado streams in east of Mato Grosso was analyzed to determine the types of substrate that contemplate the largest variation in species composition. Samples were performed in the leaf litter substrates from rapids and backwaters, root, gravel, stone (boulder), sand and on the water surface (surface tension layer) of springs, mean stretches and mouths of the Santo Antônio and Colher streams on December/2004 and July/2005, with six subsamples each substrate. Were collected 333 specimens distributed in 11 families, 20 genus and 30 morphospecies (17 Nepomorpha and 13 Gerromorpha), being Gerromorpha the most abundant (172 specimens). The estimated richness of Gerromorpha in the substrates was higher in samples from water surface, while Nepomorpha showed higher richness in root, followed by gravel and leaf litter from rapids. The inorganic substrates (stone and sand) showed lower richness of Heteroptera. Among Gerromorpha, Limnogonus aduncus aduncus Drake & Harris, Rhagovelia elegans Uhler, Neogerris lubricus White and Brachymetra sp.1 were associated to surface samples and Stridulivelia anta Polhemus & Spangler to root substrate. In Nepomorpha, Martarega chinai Hynes was associated to surface samples, while Ambrysus sp. 1 showed association to leaf litter from rapids, backwaters, root and surface. The results suggest that studies which aim for rapid surveys of Heteroptera community should prioritize surface samples for Gerromorpha and root samples for Nepomorpha, because these substrates shelter the greatest richness of each infra-order, contemplating 83% and 64% of species richness in these groups respectively

INSETOS AQUÁTICOS BIOINDICADORES DE MUDANÇAS DE USO DA TERRA NO PARÁ, BRASIL: EVIDÊNCIAS E PERSPECTIVAS

Esta revisão teve como objetivo avaliar o histórico da utilização de alguns grupos de Insetos Aquáticos como bioindicadores de alteração ambiental no estado do Pará, assim como discutir as perspectivas futuras dessa temática à luz das novas tecnologias. Verificou-se consideráveis avanços no uso das Ordens Ephemeroptera, Plecoptera, Trichoptera, Heteroptera e Odonata para monitorar a qualidade ambiental de riachos impactados por diversas atividades antrópicas. Os impactos ambientais mais proeminentes são oriundos de atividades como pecuária, agricultura, mineração, extração de madeira e urbanização. Além dos tradicionais métodos de estudos de espécies indicadoras, constatou-se que o uso de mudanças na estrutura das comunidades, em facetas como a riqueza de espécies, abundância de indivíduos e diversidade beta para monitorar a qualidade ambiental foi eficiente. Em perspectivas futuras, precisa-se conhecer melhor a biologia das espécies para que aspectos comportamentais e funcionais sejam utilizados conjuntamente com as medidas taxonômicas tradicionais para o monitoramento ambiental. Isso possibilitará uma visão mais completa de como os ecossistemas aquáticos são afetados, permitindo o planejamento de medidas mais eficazes de monitoramento e de mitigação dos impactos provocados pelas alterações ambientais na biodiversidade aquática, em especial dos insetos.  This review aimed to evaluate the history of the use of some groups of aquatic insects as environmental bioindicators in Pará State, as well as to discuss the future perspectives of this theme in the light of new technologies. Considerable advances have been made in the use of Ephemeroptera, Plecoptera, Trichoptera, Heteroptera and Odonata Orders to monitor the environmental quality of streams impacted by various anthropic activities. The most prominent environmental impacts come from activities such as livestock, agriculture, mining, logging and urbanization. In addition to the traditional methods of studying indicator species, we found that the use of the community structure, such as species richness, individual abundances and beta diversity to monitor environmental quality, were efficient. In future perspectives, it is necessary to better understand the species biology so that behavioral and functional aspects can be used together with the traditional taxonomic measures for environmental monitoring. This will enable a more complete view of how aquatic ecosystems are affected, allowing the planning of more effective measures for monitoring, and mitigating the impacts caused by environmental changes on aquatic biodiversity, especially insects