This study showed that the main impact on Odonata species of removal of riparian vegetation for r... more This study showed that the main impact on Odonata species of removal of riparian vegetation for road building was on community composition, since species richness remained unaltered. This result, most evident in damselflies, was probably driven by the entry of generalist species that replaced specialist species after the impact.We collected adult odonates in forested and deforested streams in the surroundings of Manaus, Amazonas, northern Brazil. We collected 380 specimens belonging to 32 odonate species. Erythrodiplax fusca and Argia sp. 1 could be used in biomonitoring programs, since they were significantly
associated with deforested streams. Using odonate community composition and key species appears to be more efficient in biomonitoring programs than simply using species richness.
Environmental Integrity Effect on Fluctuating Asymmetry in Erythrodiplax basalis (Libellulidae: O... more Environmental Integrity Effect on Fluctuating Asymmetry in Erythrodiplax basalis (Libellulidae: Odonata) (Kirby). Constituted by simple and cheaply techniques, measures of changes in ontogenetic development are good biomonitoring tools. One of
these techniques commonly used is the Fluctuating Asymmetry (FA). In this study, we explore the effects of riparian vegetation removal on the levels of FA on hind wings traits of Erythrodiplax basalis (Kirby). The results showed that traits present normal distribution and zero mean, which allows us to assume that observe levels of asymmetry are FA. It was also evident that FA indexes are not correlated to the wing length, and present low levels of measurement error. There is no significantly evidence of increase in the FA levels in degraded areas in comparison with preserved areas for the
measured variables (wing length, wing width on the nodus level, distance between triangle and nodus and distance between anal loop and nodus). The hypothesis that individuals collected in altered areas present higher levels of FA in wing traits was not corroborated. This may result from the fact that E. basalis is a species with good dispersal capability, and the specimens sampled in disturbed areas may have developed elsewhere and were only using the areas as a point of foraging and therefore was not detected AF. Another factor that corroborates this prediction is the fact that other studies using Zygoptera species that have lower dispersal ability, significant levels of physical activities has been detected.
We evaluated the influence of environmental integrity and the potential as bioindicator of larval... more We evaluated the influence of environmental integrity and the potential as bioindicator of larval stages of species of Trichoptera in 20 streams of first to fourth order in the Pindaı´ba river basin, Mato Grosso, Central Brazil. We measured stream integrity with the habitat integrity index (HII), establishing three levels of conservation: preserved, altered and impacted environments. We used (i) simple regression to assess the effect of habitat integrity on species abundance of Trichoptera and (ii) the indicator species analysis (IndVal) to assess the potential as bioindicator of each species. We found that 12 morphospecies showed relationship with HII: six species were bioindicators of preserved and two species of altered environments. Morphospecies that showed relationship in the two analyses (i and ii) were considered strong bioindicators, considering that the other species supported higher environmental variation, becoming evident that loss of physical structure reduces the abundance of organisms specialized in preserved environments. The results showed that the distribution and abundance of trichopterans can be an indicator of habitat integrity. Trichopteran species have bioindicator potential, corroborating the hypotheses of this work that abundance
of organisms will be smaller in environments with low integrity, and that many species are specific to preserved environments, disappearing from impacted environments, and also characteristic species of altered environments.
Many hypotheses have been proposed to explain the origin and maintenance of
the Amazonian divers... more Many hypotheses have been proposed to explain the origin and maintenance of
the Amazonian diversity with special place for the theory of isolation by rivers and a set of
hypothesis related to contemporary environmental dissimilarity. We explore those
hypotheses here using the biogeographic distributional patterns of dragonflies in interfluve
areas of the Amazonian biome and also evaluate how differences among in dispersal
capabilities between the Anisoptera and Zygoptera suborders may contribute to those
patterns. We used distributional information of 392 odonate species in the Amazonian
forest in a cladistic analysis of distributions and endemism and the estimated faunistic
similarity among interfluves with the Sorensen index. The environmental similarity among
interfluves was analysed by discriminant analysis based on eight environmental metrics.
Different metrics for geographic distance (connectivity) among interfluves were evaluated
and their relation to the other variables tested by the Mantel test. The number of endemic
species was linearly correlated to the area of the interfluves. General endemism patterns
showed consistent resemblance to those reported for vertebrates, especially the similarity
among the Rondoˆnia and Inambari interfluves. Geographical distance has no predictive
value for dragonflies distribution, but the environmental similarity is a good predictor of
proportion of shared species. The low dispersal group (Zygoptera) presented more clear
patterns of distribution and a lower proportion of shared species among different interfluves.
The environmental similarity can be considered the determinant factor of the distribution
of dragonflies, possibly due to environmental specificity evolved during a long
history of some clades in this system. The low dispersal group (Zygoptera) retained more biogeographical information about possible historical factors that determine current
distribution. Also, the transport of larvae by macrophyte banks, the lateral change of river
courses, the reversal of the drainage basin, together with the capacity to disperse across
rivers for some species may be explanations for the lack of effect of isolation by rivers,
especially for Anisoptera.
Baetidae (Insecta, Ephemeroptera) of Cerrado streams in the state of Mato Grosso, Brazil, under d... more Baetidae (Insecta, Ephemeroptera) of Cerrado streams in the state of Mato Grosso, Brazil, under different levels of environmental preservation. The effect of different stream environmental preservation levels, in 1st to 4th orders, over the richness, abundance, similarity in the composition and the potential of Baetidae (Ephemeroptera) species as bioindicators were investigated in a Cerrado region located in the state of Mato Grosso, Brazil. A total of twenty species/morphospecies were catalogued from the 1752 samples of nymphs, resulting in a new record for two species in Brazil. Values of Habitat Integrity Index (HII) were categorized among damaged, modified, and preserved
environments. Species richness was different between sites, being greater in disturbed habitats. Total abundance was higher among preserved and altered environments, and differed significantly from the degraded areas. The NMDS analysis indicates that, in preserved and modified sites, the similarity in the composition of species differs from degraded areas. Four species showed a positive relationship with increasing values of HII. Baetidae showed environmental indicator species with different levels of preservation, with Zelusia principalis Lugo-Ortiz &
McCafferty, 1998 and Baetodes sp. being indicators of preserved environments and Aturbina nigra Salles, Boldrini & Shimano, 2011, Callibaetis sp. 2, Camelobaetidius aff. janae, Paracloeodes binodulus Lugo-Ortiz & McCafferty, 1996 and Waltzoyphius roberti Thomas & Peru, 2002 as indicators of modified environments. The knowledge on the ecology of species advances in terms of providing subsidies for the biomonitoring of
basins and the use of indicator species.
Richnnes and beta diversity of Baetidae (Ephemeroptera) in streams of the Pindaíba River, Mato Gr... more Richnnes and beta diversity of Baetidae (Ephemeroptera) in streams of the Pindaíba River, Mato Grosso. The expansion of agricultural activities has led to loss of habitat heterogeneity and fall of the richness and diversity of aquatic biota, especially in the macroinvertebrate community. The components of the order Ephemeroptera comprise a group of organisms sensitive to environmental changes and respond quickly to changes occurring in the system. The family Baetidae has become an important group of mayflies in studies assessing the integrity of streams, since they are among many advantages, relevant taxonomic knowledge. Given these facts, this work has with the main objective to verify the influence of streams with different levels of integrity work on the structure of the richness and beta diversity of species of Baetidae (Insecta: Ephemeroptera) in streams of eastern Mato Grosso. The nymphs were collected in tributaries of the 1st to 4th order in five streams of river basin Pindaíba. The physical integrity of the environment was expressed by using the Index of Habitat Integrity (HII) and water samples were also taken for physicochemical analysis. We identified 1752 individuals in the family Baetidae, distributed in 11 genera and 20 species / morphospecies. The values of the Index of Habitat Integrity (HII) varied between the different environments and tributaries of that stream. There was a higher species richness in environments with intermediate levels of integrity and local children had low integrity wealth. The beta diversity was similar between the maiority of the sites, though sites with low integrity tend to have low species diversity. The values of beta diversity HII and positive effect on beta diversity. The physico-chemical water had no effect on beta diversity, except pH. The results show that variations in the physical-chemical properties of water were not prevalent in the community structure Baetidae, and the physical changes in the system the main cause of disintegration of the community of aquatic insects.
Erythrodiplax fusca Rambur, 1842 libellulidae is a small, widely distributed in the Neotropical r... more Erythrodiplax fusca Rambur, 1842 libellulidae is a small, widely distributed in the Neotropical region, categorized as percher inhabiting lentic environments. The aim of this study was to record the occurrence of sympatric specimens of E. fusca with both
abdominal color patterns in a pond of Goiás.In July 2010 we collected 12 specimens of Erythrodiplax fusca in Samambaia lake in Goiânia-GO. Of these specimens, five presented with abdominal blue pattern and seven with red pattern. This work is a record of sympatric occurrence of both forms in a pond in central-western Brazil.
Habitat fragmentation is one of the main causes of environmental degradation and a great threat t... more Habitat fragmentation is one of the main causes of environmental degradation and a great threat to world biodiversity. Fragmentation can disrupt pollination processes, affecting directly or indirectly pollinators and plants. In Brazil, the Cerrado Biome has lost most part of its vegetation cover in the last four decades, becoming a highly fragmented landscape. Those remnants have high biological diversity with high level of endemism, but very little is known about the reproductive success of their species. Cardiopetalum calophyllum Schletdl. (Annonaceae) occurs in the Cerrado of Central Brazil, has dicogamy and is pollinated by small beetle called Lobiopa insularis. The reproductive success of C. calophyllum and the abundance of its pollinator were analyzed in fragments of different sizes from July 2009 to January 2010. The reproductive success was estimated using fruit and seed set rates. Flowers in anthesis were collected to quantify the pollinator abundance inside them. A positive correlation between reproductive success of C. calophyllum and the fragment size was found. However, no correlation was found between pollinator abundance and fragment size. The abundance of Lobiopa insularis seems to be more related to its generalist habits than to the fragment size. In our study, the effect of fragment size and reproductive success of C. calophyllum was stronger in fragments smaller than 10 ha. But fragments smaller than 20 ha also showed a decrease in their reproductive success.
Composition and distribution of Ephemeroptera (Insecta) in Cerrado-Amazônia transition area, Braz... more Composition and distribution of Ephemeroptera (Insecta) in Cerrado-Amazônia transition area, Brazil. The objective of this study was to respond if exist a pattern on the spatial distributions of Ephemeroptera nymphs in different streams and rivers from Suiá-Miçú Basin, MT, and how the streams are classifying according to the species composition. Were sample 12 streams and rivers, in three periods of the year. Were collected 1,356 individuals, distributed in seven families, 31 genus and 42 species and/or morphospecies. The most abundant locals were semi-lentics and with few shaded suggering that most light in the system offer, allochthonous material and autochthonous material like food resources. The greater estimates richness was found in lotic places, emphasizing that the Ephemeroptera presents greater richness in these places, once water current is essential for organic matter transporting. So much in the grouping analysis (TWINSPAM) as in the ordination (DCA) was observed the separation of lotic and semi-lentic environments as for species composition. It had a gradient in the composition similarity of lotic and small streams for lotic and big stream and for last, semilentics.
The results of this study show that the physic structure of aquatic environments affect species composition. In that way, retreat
of riparian vegetation and streams dam up can take significant losses in the diversity.
Effects of riparian vegetation removal on body size and wing fluctuating asymmetry (FA) of Argia ... more Effects of riparian vegetation removal on body size and wing fluctuating asymmetry (FA) of Argia tinctipennis Selys (Odonata: Coenagrionidae) were studied in the River Suiá-Miçú basin, which is part of the Xingu basin in Brazilian Amazonia. A total of 70 specimens (n033 from preserved and n037 from degraded areas) was measured. Five wing measures of each wing (totalizing ten measured characters) were taken. Preserved and degraded points presented non-overlapped variations of a Habitat Integrity Index, supporting the environmental differentiation between these two categories. FA increases in degraded areas approximately
four times for the width between the nodus and proximal
portion of the pterostigma of forewings (FW), two times for the width of the wing in the region of nodus of FW, and approximately 1.7 times for the number of postnodal cells of FW. The increase is almost five times for the width between the nodus and the proximal portion of the pterostigma of hind wings (HW), three times for the number of postnodal cells of HW, and approximately 1.6 times the width between quadrangle and nodus of HW. Individuals of preserved sites were nearly 3.3% larger than for degraded sites, based on mean hind wing length. Our results supports that the development of A. tinctipennis in degraded
areas is affected by riparian vegetation removal and may reflect in wing FA variations. Consequently, these FA measures may be a useful tool for bioassessment using Odonata insects as a model.
The composition, abundance and species diversity of Trichoptera immatures was studied in 12 tribu... more The composition, abundance and species diversity of Trichoptera immatures was studied in 12 tributaries of Suiá-Miçú River Basin, a mosaic of wetlands, streams and rivers tributary of the Xingu River in the Cerrado-Amazonian Forest transition zone in Mato Grosso, Brazil. The varying sizes, flow types and conservation levels of the tributaries were sampled through three periods between 2007 and 2008 by the use of fixed transects along the environments margins. A total of 867 larvae was collected (divided in seven families, 17 genera, 49 species/ morphospecies) with the most abundant and rich families being Hydropsychidae and Leptoceridae and the most abundant species Leptonema
sparsum (n = 370). There has been loss of species richness in impacted, large and lentic environments. Composition variations related to the flow, the vegetation type and the interaction between conservation levels and flow was detected. Conservation levels, width and the quantitative habitat integrity index (HII) did not influence the Trichoptera composition. These results may encourage further investigation of impact effects on aquatic
insect compositions and pattern of distribution in the transition area between the Cerrado and the Amazonian Forest.
The distribution and composition of aquatic insect communities in streams at a local scale are co... more The distribution and composition of aquatic insect communities in streams at a local scale are considered to be primarily determined by environmental factors and interactive relationships within the
system. Here, we evaluated the effects of forest fragmentation and forest cover changes on habitat characteristics of streamlets (igarape´s) in Amazonian forests and on the aquatic insect communities found there.Wealso developed a habitat integrity index (HII) based on Petersen’s protocol (1992) to evaluate
physical integrity of these streamlets and to determine its efficiency to interpret the environmental impacts on this system. We studied 20 small streams at the Biological Dynamics of Forest Fragments Project (BDFFP INPA/SI) study areas, Central Amazonia, 80 km north of Manaus, Amazonas State, Brazil. The
vegetation cover was estimated by using LANDSAT images and classified in the following categories: exposed soil, pastures, secondary forests (capoeiras), and primary forests. Stream habitat features were evaluated by using a HII based on visual assessment of local characteristics. Aquatic insects were sampled in four major stream substrates: litter deposited in pools
or backwaters, litter retained in riffles, sand, and marginal banks. Stream habitat characteristics were significantly correlated to land use and riparian forest condition. Overall aquatic insect richness and Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness were significantly lower in pasture streams, and their
taxonomic composition differed significantly from streams in forested areas. However, these metrics were not significantly correlated to the stream HII. Taxonomic composition of bank insect assemblages changed significantly between streams with low and high values of HII. There was no significant relationship
between the proportion of primary forest cover and the faunal metrics. Only drastic changes in the vegetal cover seem to induce significant changes in the aquatic insect community. Matrix habitat heterogeneity, distance to forest fragments, the presence of areas of secondary forest, and the intrinsic capacity to
disperse in many of the insect groups may have contributed to attenuate the effects of habitat disturbance on aquatic insect assemblages in streamlets.
Structural properties of aquatic habitats are the basis of several theories produced to explain t... more Structural properties of aquatic habitats are the basis of several theories produced to explain the functioning of aquatic environments. We predicted a longitudinal change of ecosystem
properties along the river, and also that potamal areas of the river are similar to lakes. In rivers with periodic floods we also expect a high degree of similarity due to increased environmental
similarity and increase dispersal of component species. Otherwise, rivers must be conceived as a landscape element with an intrinsic hierarchical nature and dispersal among its parts are constrained by this structure. Under this view, we also could expect that different basin or different ‘‘micro-basin’’ could present communities that are historically different in their general properties. Here, we aimed to describe odonate larval
communities in the Pantanal Mortes-Araguaia river basin in Brazil comparing the composition, species richness and community structure between lakes and rivers, and also the possible
differences among river basins. The field work was done in three rivers and three lakes chosen to conform to a paired experiment, each pair in a different river basin. An aggregated sampling unit
was used based on Ekman dredge and D-nets replicated on each site. We sampled 936 individuals distributed in 30 genera and a total of 34 morphotypes. There was no difference in species
richness among lakes and rivers, but a marked difference among basins. Samples from the same basin present a higher similarity of the species abundance relations than among river or lake
samples. We also did not observed differences in composition and community structure between large rivers and lakes, in the same basin. The results supported the concept of structural similarity
between large rivers and lakes and the differences observed among basins could indicate historical events in colonization that are shaping communities characteristics.
1. The Amazon region is formed primarily by a dense network of acid and nutrient-poor streamlets.... more 1. The Amazon region is formed primarily by a dense network of acid and nutrient-poor streamlets. The stability of environmental conditions coupled with spatial constraints to dispersal turns these streamlets into an interesting arena to compare neutral and niche drivers for community organisation. Here, we evaluated
the relative importance of local environmental conditions and regional dispersal limitation to determine beta-diversity and distributional patterns of species richness of the adult Odonata assemblage present in the Adolpho Ducke Forest Reserve (Manaus, Amazon) river basins.
2. Samples were taken in 24 streamlets distributed in four river sub-basins (pairwise distances up to 10 km) during the rainy season. The samples consisted of visual surveys for adult individuals of Odonata present in 100 m transects along each
streamlet; each transect was divided into 20 segments of 5 m.
3. A total of 17 species were observed and 23 (4.8) were estimated using a jackknife procedure. Four sub-basins were statistically similar based on species richness and beta-diversity. Distance among the streamlets had a low predictive power for species richness, while beta-diversity patterns were mainly explained by local environmental variables (channel width and depth). The low values of the beta-diversity index may be attributed to the high similarity of the environment, which presented little variation in abiotic conditions.
4. Low dispersal constraints and environmental stability are the primary explanations for low beta-diversity at this spatial extension. Nevertheless, the importance of local environmental variables to determine beta-diversity suggests its inclusion as criteria for setting conservation priorities for this group.
The aquatic and semi-aquatic Heteroptera represent a group of insects with a multitude of shapes,... more The aquatic and semi-aquatic Heteroptera represent a group of insects with a multitude of shapes, being the result of adaptations to a broad niche variety. Heteroptera were collected in five streams (from 1st to 4th order) in the Pindaíba River Basin, in order to, with different in the habitat integrity: (1) correlate the species richness with the Habitat Integrity Index and water physical-chemical parameters; and (2) to determine which species are capable to serve as bioindicators. In each stream, linear transects of 100m were demarcated. 1,425 specimens from 10 families, 30 genera and 67 morphospecies were collected. Nitrate negatively affected Nepomorpha and temperature with Gerromorpha species richness. The matrix of environmental variables showed no influence on the distribution of species. Three species (Rhagovelia trailli (White, 1879), Rhagovelia sp.4 and Tenagobia incerta Lundblad, 1928) were considered to be indicators of pristine sites. The results indicate that Gerromorpha can be an important tool to assess environmental habitat integrity and enhance conservation actions of riparian forests.
This study showed that the main impact on Odonata species of removal of riparian vegetation for r... more This study showed that the main impact on Odonata species of removal of riparian vegetation for road building was on community composition, since species richness remained unaltered. This result, most evident in damselflies, was probably driven by the entry of generalist species that replaced specialist species after the impact.We collected adult odonates in forested and deforested streams in the surroundings of Manaus, Amazonas, northern Brazil. We collected 380 specimens belonging to 32 odonate species. Erythrodiplax fusca and Argia sp. 1 could be used in biomonitoring programs, since they were significantly
associated with deforested streams. Using odonate community composition and key species appears to be more efficient in biomonitoring programs than simply using species richness.
Environmental Integrity Effect on Fluctuating Asymmetry in Erythrodiplax basalis (Libellulidae: O... more Environmental Integrity Effect on Fluctuating Asymmetry in Erythrodiplax basalis (Libellulidae: Odonata) (Kirby). Constituted by simple and cheaply techniques, measures of changes in ontogenetic development are good biomonitoring tools. One of
these techniques commonly used is the Fluctuating Asymmetry (FA). In this study, we explore the effects of riparian vegetation removal on the levels of FA on hind wings traits of Erythrodiplax basalis (Kirby). The results showed that traits present normal distribution and zero mean, which allows us to assume that observe levels of asymmetry are FA. It was also evident that FA indexes are not correlated to the wing length, and present low levels of measurement error. There is no significantly evidence of increase in the FA levels in degraded areas in comparison with preserved areas for the
measured variables (wing length, wing width on the nodus level, distance between triangle and nodus and distance between anal loop and nodus). The hypothesis that individuals collected in altered areas present higher levels of FA in wing traits was not corroborated. This may result from the fact that E. basalis is a species with good dispersal capability, and the specimens sampled in disturbed areas may have developed elsewhere and were only using the areas as a point of foraging and therefore was not detected AF. Another factor that corroborates this prediction is the fact that other studies using Zygoptera species that have lower dispersal ability, significant levels of physical activities has been detected.
We evaluated the influence of environmental integrity and the potential as bioindicator of larval... more We evaluated the influence of environmental integrity and the potential as bioindicator of larval stages of species of Trichoptera in 20 streams of first to fourth order in the Pindaı´ba river basin, Mato Grosso, Central Brazil. We measured stream integrity with the habitat integrity index (HII), establishing three levels of conservation: preserved, altered and impacted environments. We used (i) simple regression to assess the effect of habitat integrity on species abundance of Trichoptera and (ii) the indicator species analysis (IndVal) to assess the potential as bioindicator of each species. We found that 12 morphospecies showed relationship with HII: six species were bioindicators of preserved and two species of altered environments. Morphospecies that showed relationship in the two analyses (i and ii) were considered strong bioindicators, considering that the other species supported higher environmental variation, becoming evident that loss of physical structure reduces the abundance of organisms specialized in preserved environments. The results showed that the distribution and abundance of trichopterans can be an indicator of habitat integrity. Trichopteran species have bioindicator potential, corroborating the hypotheses of this work that abundance
of organisms will be smaller in environments with low integrity, and that many species are specific to preserved environments, disappearing from impacted environments, and also characteristic species of altered environments.
Many hypotheses have been proposed to explain the origin and maintenance of
the Amazonian divers... more Many hypotheses have been proposed to explain the origin and maintenance of
the Amazonian diversity with special place for the theory of isolation by rivers and a set of
hypothesis related to contemporary environmental dissimilarity. We explore those
hypotheses here using the biogeographic distributional patterns of dragonflies in interfluve
areas of the Amazonian biome and also evaluate how differences among in dispersal
capabilities between the Anisoptera and Zygoptera suborders may contribute to those
patterns. We used distributional information of 392 odonate species in the Amazonian
forest in a cladistic analysis of distributions and endemism and the estimated faunistic
similarity among interfluves with the Sorensen index. The environmental similarity among
interfluves was analysed by discriminant analysis based on eight environmental metrics.
Different metrics for geographic distance (connectivity) among interfluves were evaluated
and their relation to the other variables tested by the Mantel test. The number of endemic
species was linearly correlated to the area of the interfluves. General endemism patterns
showed consistent resemblance to those reported for vertebrates, especially the similarity
among the Rondoˆnia and Inambari interfluves. Geographical distance has no predictive
value for dragonflies distribution, but the environmental similarity is a good predictor of
proportion of shared species. The low dispersal group (Zygoptera) presented more clear
patterns of distribution and a lower proportion of shared species among different interfluves.
The environmental similarity can be considered the determinant factor of the distribution
of dragonflies, possibly due to environmental specificity evolved during a long
history of some clades in this system. The low dispersal group (Zygoptera) retained more biogeographical information about possible historical factors that determine current
distribution. Also, the transport of larvae by macrophyte banks, the lateral change of river
courses, the reversal of the drainage basin, together with the capacity to disperse across
rivers for some species may be explanations for the lack of effect of isolation by rivers,
especially for Anisoptera.
Baetidae (Insecta, Ephemeroptera) of Cerrado streams in the state of Mato Grosso, Brazil, under d... more Baetidae (Insecta, Ephemeroptera) of Cerrado streams in the state of Mato Grosso, Brazil, under different levels of environmental preservation. The effect of different stream environmental preservation levels, in 1st to 4th orders, over the richness, abundance, similarity in the composition and the potential of Baetidae (Ephemeroptera) species as bioindicators were investigated in a Cerrado region located in the state of Mato Grosso, Brazil. A total of twenty species/morphospecies were catalogued from the 1752 samples of nymphs, resulting in a new record for two species in Brazil. Values of Habitat Integrity Index (HII) were categorized among damaged, modified, and preserved
environments. Species richness was different between sites, being greater in disturbed habitats. Total abundance was higher among preserved and altered environments, and differed significantly from the degraded areas. The NMDS analysis indicates that, in preserved and modified sites, the similarity in the composition of species differs from degraded areas. Four species showed a positive relationship with increasing values of HII. Baetidae showed environmental indicator species with different levels of preservation, with Zelusia principalis Lugo-Ortiz &
McCafferty, 1998 and Baetodes sp. being indicators of preserved environments and Aturbina nigra Salles, Boldrini & Shimano, 2011, Callibaetis sp. 2, Camelobaetidius aff. janae, Paracloeodes binodulus Lugo-Ortiz & McCafferty, 1996 and Waltzoyphius roberti Thomas & Peru, 2002 as indicators of modified environments. The knowledge on the ecology of species advances in terms of providing subsidies for the biomonitoring of
basins and the use of indicator species.
Richnnes and beta diversity of Baetidae (Ephemeroptera) in streams of the Pindaíba River, Mato Gr... more Richnnes and beta diversity of Baetidae (Ephemeroptera) in streams of the Pindaíba River, Mato Grosso. The expansion of agricultural activities has led to loss of habitat heterogeneity and fall of the richness and diversity of aquatic biota, especially in the macroinvertebrate community. The components of the order Ephemeroptera comprise a group of organisms sensitive to environmental changes and respond quickly to changes occurring in the system. The family Baetidae has become an important group of mayflies in studies assessing the integrity of streams, since they are among many advantages, relevant taxonomic knowledge. Given these facts, this work has with the main objective to verify the influence of streams with different levels of integrity work on the structure of the richness and beta diversity of species of Baetidae (Insecta: Ephemeroptera) in streams of eastern Mato Grosso. The nymphs were collected in tributaries of the 1st to 4th order in five streams of river basin Pindaíba. The physical integrity of the environment was expressed by using the Index of Habitat Integrity (HII) and water samples were also taken for physicochemical analysis. We identified 1752 individuals in the family Baetidae, distributed in 11 genera and 20 species / morphospecies. The values of the Index of Habitat Integrity (HII) varied between the different environments and tributaries of that stream. There was a higher species richness in environments with intermediate levels of integrity and local children had low integrity wealth. The beta diversity was similar between the maiority of the sites, though sites with low integrity tend to have low species diversity. The values of beta diversity HII and positive effect on beta diversity. The physico-chemical water had no effect on beta diversity, except pH. The results show that variations in the physical-chemical properties of water were not prevalent in the community structure Baetidae, and the physical changes in the system the main cause of disintegration of the community of aquatic insects.
Erythrodiplax fusca Rambur, 1842 libellulidae is a small, widely distributed in the Neotropical r... more Erythrodiplax fusca Rambur, 1842 libellulidae is a small, widely distributed in the Neotropical region, categorized as percher inhabiting lentic environments. The aim of this study was to record the occurrence of sympatric specimens of E. fusca with both
abdominal color patterns in a pond of Goiás.In July 2010 we collected 12 specimens of Erythrodiplax fusca in Samambaia lake in Goiânia-GO. Of these specimens, five presented with abdominal blue pattern and seven with red pattern. This work is a record of sympatric occurrence of both forms in a pond in central-western Brazil.
Habitat fragmentation is one of the main causes of environmental degradation and a great threat t... more Habitat fragmentation is one of the main causes of environmental degradation and a great threat to world biodiversity. Fragmentation can disrupt pollination processes, affecting directly or indirectly pollinators and plants. In Brazil, the Cerrado Biome has lost most part of its vegetation cover in the last four decades, becoming a highly fragmented landscape. Those remnants have high biological diversity with high level of endemism, but very little is known about the reproductive success of their species. Cardiopetalum calophyllum Schletdl. (Annonaceae) occurs in the Cerrado of Central Brazil, has dicogamy and is pollinated by small beetle called Lobiopa insularis. The reproductive success of C. calophyllum and the abundance of its pollinator were analyzed in fragments of different sizes from July 2009 to January 2010. The reproductive success was estimated using fruit and seed set rates. Flowers in anthesis were collected to quantify the pollinator abundance inside them. A positive correlation between reproductive success of C. calophyllum and the fragment size was found. However, no correlation was found between pollinator abundance and fragment size. The abundance of Lobiopa insularis seems to be more related to its generalist habits than to the fragment size. In our study, the effect of fragment size and reproductive success of C. calophyllum was stronger in fragments smaller than 10 ha. But fragments smaller than 20 ha also showed a decrease in their reproductive success.
Composition and distribution of Ephemeroptera (Insecta) in Cerrado-Amazônia transition area, Braz... more Composition and distribution of Ephemeroptera (Insecta) in Cerrado-Amazônia transition area, Brazil. The objective of this study was to respond if exist a pattern on the spatial distributions of Ephemeroptera nymphs in different streams and rivers from Suiá-Miçú Basin, MT, and how the streams are classifying according to the species composition. Were sample 12 streams and rivers, in three periods of the year. Were collected 1,356 individuals, distributed in seven families, 31 genus and 42 species and/or morphospecies. The most abundant locals were semi-lentics and with few shaded suggering that most light in the system offer, allochthonous material and autochthonous material like food resources. The greater estimates richness was found in lotic places, emphasizing that the Ephemeroptera presents greater richness in these places, once water current is essential for organic matter transporting. So much in the grouping analysis (TWINSPAM) as in the ordination (DCA) was observed the separation of lotic and semi-lentic environments as for species composition. It had a gradient in the composition similarity of lotic and small streams for lotic and big stream and for last, semilentics.
The results of this study show that the physic structure of aquatic environments affect species composition. In that way, retreat
of riparian vegetation and streams dam up can take significant losses in the diversity.
Effects of riparian vegetation removal on body size and wing fluctuating asymmetry (FA) of Argia ... more Effects of riparian vegetation removal on body size and wing fluctuating asymmetry (FA) of Argia tinctipennis Selys (Odonata: Coenagrionidae) were studied in the River Suiá-Miçú basin, which is part of the Xingu basin in Brazilian Amazonia. A total of 70 specimens (n033 from preserved and n037 from degraded areas) was measured. Five wing measures of each wing (totalizing ten measured characters) were taken. Preserved and degraded points presented non-overlapped variations of a Habitat Integrity Index, supporting the environmental differentiation between these two categories. FA increases in degraded areas approximately
four times for the width between the nodus and proximal
portion of the pterostigma of forewings (FW), two times for the width of the wing in the region of nodus of FW, and approximately 1.7 times for the number of postnodal cells of FW. The increase is almost five times for the width between the nodus and the proximal portion of the pterostigma of hind wings (HW), three times for the number of postnodal cells of HW, and approximately 1.6 times the width between quadrangle and nodus of HW. Individuals of preserved sites were nearly 3.3% larger than for degraded sites, based on mean hind wing length. Our results supports that the development of A. tinctipennis in degraded
areas is affected by riparian vegetation removal and may reflect in wing FA variations. Consequently, these FA measures may be a useful tool for bioassessment using Odonata insects as a model.
The composition, abundance and species diversity of Trichoptera immatures was studied in 12 tribu... more The composition, abundance and species diversity of Trichoptera immatures was studied in 12 tributaries of Suiá-Miçú River Basin, a mosaic of wetlands, streams and rivers tributary of the Xingu River in the Cerrado-Amazonian Forest transition zone in Mato Grosso, Brazil. The varying sizes, flow types and conservation levels of the tributaries were sampled through three periods between 2007 and 2008 by the use of fixed transects along the environments margins. A total of 867 larvae was collected (divided in seven families, 17 genera, 49 species/ morphospecies) with the most abundant and rich families being Hydropsychidae and Leptoceridae and the most abundant species Leptonema
sparsum (n = 370). There has been loss of species richness in impacted, large and lentic environments. Composition variations related to the flow, the vegetation type and the interaction between conservation levels and flow was detected. Conservation levels, width and the quantitative habitat integrity index (HII) did not influence the Trichoptera composition. These results may encourage further investigation of impact effects on aquatic
insect compositions and pattern of distribution in the transition area between the Cerrado and the Amazonian Forest.
The distribution and composition of aquatic insect communities in streams at a local scale are co... more The distribution and composition of aquatic insect communities in streams at a local scale are considered to be primarily determined by environmental factors and interactive relationships within the
system. Here, we evaluated the effects of forest fragmentation and forest cover changes on habitat characteristics of streamlets (igarape´s) in Amazonian forests and on the aquatic insect communities found there.Wealso developed a habitat integrity index (HII) based on Petersen’s protocol (1992) to evaluate
physical integrity of these streamlets and to determine its efficiency to interpret the environmental impacts on this system. We studied 20 small streams at the Biological Dynamics of Forest Fragments Project (BDFFP INPA/SI) study areas, Central Amazonia, 80 km north of Manaus, Amazonas State, Brazil. The
vegetation cover was estimated by using LANDSAT images and classified in the following categories: exposed soil, pastures, secondary forests (capoeiras), and primary forests. Stream habitat features were evaluated by using a HII based on visual assessment of local characteristics. Aquatic insects were sampled in four major stream substrates: litter deposited in pools
or backwaters, litter retained in riffles, sand, and marginal banks. Stream habitat characteristics were significantly correlated to land use and riparian forest condition. Overall aquatic insect richness and Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness were significantly lower in pasture streams, and their
taxonomic composition differed significantly from streams in forested areas. However, these metrics were not significantly correlated to the stream HII. Taxonomic composition of bank insect assemblages changed significantly between streams with low and high values of HII. There was no significant relationship
between the proportion of primary forest cover and the faunal metrics. Only drastic changes in the vegetal cover seem to induce significant changes in the aquatic insect community. Matrix habitat heterogeneity, distance to forest fragments, the presence of areas of secondary forest, and the intrinsic capacity to
disperse in many of the insect groups may have contributed to attenuate the effects of habitat disturbance on aquatic insect assemblages in streamlets.
Structural properties of aquatic habitats are the basis of several theories produced to explain t... more Structural properties of aquatic habitats are the basis of several theories produced to explain the functioning of aquatic environments. We predicted a longitudinal change of ecosystem
properties along the river, and also that potamal areas of the river are similar to lakes. In rivers with periodic floods we also expect a high degree of similarity due to increased environmental
similarity and increase dispersal of component species. Otherwise, rivers must be conceived as a landscape element with an intrinsic hierarchical nature and dispersal among its parts are constrained by this structure. Under this view, we also could expect that different basin or different ‘‘micro-basin’’ could present communities that are historically different in their general properties. Here, we aimed to describe odonate larval
communities in the Pantanal Mortes-Araguaia river basin in Brazil comparing the composition, species richness and community structure between lakes and rivers, and also the possible
differences among river basins. The field work was done in three rivers and three lakes chosen to conform to a paired experiment, each pair in a different river basin. An aggregated sampling unit
was used based on Ekman dredge and D-nets replicated on each site. We sampled 936 individuals distributed in 30 genera and a total of 34 morphotypes. There was no difference in species
richness among lakes and rivers, but a marked difference among basins. Samples from the same basin present a higher similarity of the species abundance relations than among river or lake
samples. We also did not observed differences in composition and community structure between large rivers and lakes, in the same basin. The results supported the concept of structural similarity
between large rivers and lakes and the differences observed among basins could indicate historical events in colonization that are shaping communities characteristics.
1. The Amazon region is formed primarily by a dense network of acid and nutrient-poor streamlets.... more 1. The Amazon region is formed primarily by a dense network of acid and nutrient-poor streamlets. The stability of environmental conditions coupled with spatial constraints to dispersal turns these streamlets into an interesting arena to compare neutral and niche drivers for community organisation. Here, we evaluated
the relative importance of local environmental conditions and regional dispersal limitation to determine beta-diversity and distributional patterns of species richness of the adult Odonata assemblage present in the Adolpho Ducke Forest Reserve (Manaus, Amazon) river basins.
2. Samples were taken in 24 streamlets distributed in four river sub-basins (pairwise distances up to 10 km) during the rainy season. The samples consisted of visual surveys for adult individuals of Odonata present in 100 m transects along each
streamlet; each transect was divided into 20 segments of 5 m.
3. A total of 17 species were observed and 23 (4.8) were estimated using a jackknife procedure. Four sub-basins were statistically similar based on species richness and beta-diversity. Distance among the streamlets had a low predictive power for species richness, while beta-diversity patterns were mainly explained by local environmental variables (channel width and depth). The low values of the beta-diversity index may be attributed to the high similarity of the environment, which presented little variation in abiotic conditions.
4. Low dispersal constraints and environmental stability are the primary explanations for low beta-diversity at this spatial extension. Nevertheless, the importance of local environmental variables to determine beta-diversity suggests its inclusion as criteria for setting conservation priorities for this group.
The aquatic and semi-aquatic Heteroptera represent a group of insects with a multitude of shapes,... more The aquatic and semi-aquatic Heteroptera represent a group of insects with a multitude of shapes, being the result of adaptations to a broad niche variety. Heteroptera were collected in five streams (from 1st to 4th order) in the Pindaíba River Basin, in order to, with different in the habitat integrity: (1) correlate the species richness with the Habitat Integrity Index and water physical-chemical parameters; and (2) to determine which species are capable to serve as bioindicators. In each stream, linear transects of 100m were demarcated. 1,425 specimens from 10 families, 30 genera and 67 morphospecies were collected. Nitrate negatively affected Nepomorpha and temperature with Gerromorpha species richness. The matrix of environmental variables showed no influence on the distribution of species. Three species (Rhagovelia trailli (White, 1879), Rhagovelia sp.4 and Tenagobia incerta Lundblad, 1928) were considered to be indicators of pristine sites. The results indicate that Gerromorpha can be an important tool to assess environmental habitat integrity and enhance conservation actions of riparian forests.
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Papers by Leandro Juen
associated with deforested streams. Using odonate community composition and key species appears to be more efficient in biomonitoring programs than simply using species richness.
these techniques commonly used is the Fluctuating Asymmetry (FA). In this study, we explore the effects of riparian vegetation removal on the levels of FA on hind wings traits of Erythrodiplax basalis (Kirby). The results showed that traits present normal distribution and zero mean, which allows us to assume that observe levels of asymmetry are FA. It was also evident that FA indexes are not correlated to the wing length, and present low levels of measurement error. There is no significantly evidence of increase in the FA levels in degraded areas in comparison with preserved areas for the
measured variables (wing length, wing width on the nodus level, distance between triangle and nodus and distance between anal loop and nodus). The hypothesis that individuals collected in altered areas present higher levels of FA in wing traits was not corroborated. This may result from the fact that E. basalis is a species with good dispersal capability, and the specimens sampled in disturbed areas may have developed elsewhere and were only using the areas as a point of foraging and therefore was not detected AF. Another factor that corroborates this prediction is the fact that other studies using Zygoptera species that have lower dispersal ability, significant levels of physical activities has been detected.
of organisms will be smaller in environments with low integrity, and that many species are specific to preserved environments, disappearing from impacted environments, and also characteristic species of altered environments.
the Amazonian diversity with special place for the theory of isolation by rivers and a set of
hypothesis related to contemporary environmental dissimilarity. We explore those
hypotheses here using the biogeographic distributional patterns of dragonflies in interfluve
areas of the Amazonian biome and also evaluate how differences among in dispersal
capabilities between the Anisoptera and Zygoptera suborders may contribute to those
patterns. We used distributional information of 392 odonate species in the Amazonian
forest in a cladistic analysis of distributions and endemism and the estimated faunistic
similarity among interfluves with the Sorensen index. The environmental similarity among
interfluves was analysed by discriminant analysis based on eight environmental metrics.
Different metrics for geographic distance (connectivity) among interfluves were evaluated
and their relation to the other variables tested by the Mantel test. The number of endemic
species was linearly correlated to the area of the interfluves. General endemism patterns
showed consistent resemblance to those reported for vertebrates, especially the similarity
among the Rondoˆnia and Inambari interfluves. Geographical distance has no predictive
value for dragonflies distribution, but the environmental similarity is a good predictor of
proportion of shared species. The low dispersal group (Zygoptera) presented more clear
patterns of distribution and a lower proportion of shared species among different interfluves.
The environmental similarity can be considered the determinant factor of the distribution
of dragonflies, possibly due to environmental specificity evolved during a long
history of some clades in this system. The low dispersal group (Zygoptera) retained more biogeographical information about possible historical factors that determine current
distribution. Also, the transport of larvae by macrophyte banks, the lateral change of river
courses, the reversal of the drainage basin, together with the capacity to disperse across
rivers for some species may be explanations for the lack of effect of isolation by rivers,
especially for Anisoptera.
environments. Species richness was different between sites, being greater in disturbed habitats. Total abundance was higher among preserved and altered environments, and differed significantly from the degraded areas. The NMDS analysis indicates that, in preserved and modified sites, the similarity in the composition of species differs from degraded areas. Four species showed a positive relationship with increasing values of HII. Baetidae showed environmental indicator species with different levels of preservation, with Zelusia principalis Lugo-Ortiz &
McCafferty, 1998 and Baetodes sp. being indicators of preserved environments and Aturbina nigra Salles, Boldrini & Shimano, 2011, Callibaetis sp. 2, Camelobaetidius aff. janae, Paracloeodes binodulus Lugo-Ortiz & McCafferty, 1996 and Waltzoyphius roberti Thomas & Peru, 2002 as indicators of modified environments. The knowledge on the ecology of species advances in terms of providing subsidies for the biomonitoring of
basins and the use of indicator species.
abdominal color patterns in a pond of Goiás.In July 2010 we collected 12 specimens of Erythrodiplax fusca in Samambaia lake in Goiânia-GO. Of these specimens, five presented with abdominal blue pattern and seven with red pattern. This work is a record of sympatric occurrence of both forms in a pond in central-western Brazil.
The results of this study show that the physic structure of aquatic environments affect species composition. In that way, retreat
of riparian vegetation and streams dam up can take significant losses in the diversity.
four times for the width between the nodus and proximal
portion of the pterostigma of forewings (FW), two times for the width of the wing in the region of nodus of FW, and approximately 1.7 times for the number of postnodal cells of FW. The increase is almost five times for the width between the nodus and the proximal portion of the pterostigma of hind wings (HW), three times for the number of postnodal cells of HW, and approximately 1.6 times the width between quadrangle and nodus of HW. Individuals of preserved sites were nearly 3.3% larger than for degraded sites, based on mean hind wing length. Our results supports that the development of A. tinctipennis in degraded
areas is affected by riparian vegetation removal and may reflect in wing FA variations. Consequently, these FA measures may be a useful tool for bioassessment using Odonata insects as a model.
sparsum (n = 370). There has been loss of species richness in impacted, large and lentic environments. Composition variations related to the flow, the vegetation type and the interaction between conservation levels and flow was detected. Conservation levels, width and the quantitative habitat integrity index (HII) did not influence the Trichoptera composition. These results may encourage further investigation of impact effects on aquatic
insect compositions and pattern of distribution in the transition area between the Cerrado and the Amazonian Forest.
system. Here, we evaluated the effects of forest fragmentation and forest cover changes on habitat characteristics of streamlets (igarape´s) in Amazonian forests and on the aquatic insect communities found there.Wealso developed a habitat integrity index (HII) based on Petersen’s protocol (1992) to evaluate
physical integrity of these streamlets and to determine its efficiency to interpret the environmental impacts on this system. We studied 20 small streams at the Biological Dynamics of Forest Fragments Project (BDFFP INPA/SI) study areas, Central Amazonia, 80 km north of Manaus, Amazonas State, Brazil. The
vegetation cover was estimated by using LANDSAT images and classified in the following categories: exposed soil, pastures, secondary forests (capoeiras), and primary forests. Stream habitat features were evaluated by using a HII based on visual assessment of local characteristics. Aquatic insects were sampled in four major stream substrates: litter deposited in pools
or backwaters, litter retained in riffles, sand, and marginal banks. Stream habitat characteristics were significantly correlated to land use and riparian forest condition. Overall aquatic insect richness and Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness were significantly lower in pasture streams, and their
taxonomic composition differed significantly from streams in forested areas. However, these metrics were not significantly correlated to the stream HII. Taxonomic composition of bank insect assemblages changed significantly between streams with low and high values of HII. There was no significant relationship
between the proportion of primary forest cover and the faunal metrics. Only drastic changes in the vegetal cover seem to induce significant changes in the aquatic insect community. Matrix habitat heterogeneity, distance to forest fragments, the presence of areas of secondary forest, and the intrinsic capacity to
disperse in many of the insect groups may have contributed to attenuate the effects of habitat disturbance on aquatic insect assemblages in streamlets.
properties along the river, and also that potamal areas of the river are similar to lakes. In rivers with periodic floods we also expect a high degree of similarity due to increased environmental
similarity and increase dispersal of component species. Otherwise, rivers must be conceived as a landscape element with an intrinsic hierarchical nature and dispersal among its parts are constrained by this structure. Under this view, we also could expect that different basin or different ‘‘micro-basin’’ could present communities that are historically different in their general properties. Here, we aimed to describe odonate larval
communities in the Pantanal Mortes-Araguaia river basin in Brazil comparing the composition, species richness and community structure between lakes and rivers, and also the possible
differences among river basins. The field work was done in three rivers and three lakes chosen to conform to a paired experiment, each pair in a different river basin. An aggregated sampling unit
was used based on Ekman dredge and D-nets replicated on each site. We sampled 936 individuals distributed in 30 genera and a total of 34 morphotypes. There was no difference in species
richness among lakes and rivers, but a marked difference among basins. Samples from the same basin present a higher similarity of the species abundance relations than among river or lake
samples. We also did not observed differences in composition and community structure between large rivers and lakes, in the same basin. The results supported the concept of structural similarity
between large rivers and lakes and the differences observed among basins could indicate historical events in colonization that are shaping communities characteristics.
the relative importance of local environmental conditions and regional dispersal limitation to determine beta-diversity and distributional patterns of species richness of the adult Odonata assemblage present in the Adolpho Ducke Forest Reserve (Manaus, Amazon) river basins.
2. Samples were taken in 24 streamlets distributed in four river sub-basins (pairwise distances up to 10 km) during the rainy season. The samples consisted of visual surveys for adult individuals of Odonata present in 100 m transects along each
streamlet; each transect was divided into 20 segments of 5 m.
3. A total of 17 species were observed and 23 (4.8) were estimated using a jackknife procedure. Four sub-basins were statistically similar based on species richness and beta-diversity. Distance among the streamlets had a low predictive power for species richness, while beta-diversity patterns were mainly explained by local environmental variables (channel width and depth). The low values of the beta-diversity index may be attributed to the high similarity of the environment, which presented little variation in abiotic conditions.
4. Low dispersal constraints and environmental stability are the primary explanations for low beta-diversity at this spatial extension. Nevertheless, the importance of local environmental variables to determine beta-diversity suggests its inclusion as criteria for setting conservation priorities for this group.
associated with deforested streams. Using odonate community composition and key species appears to be more efficient in biomonitoring programs than simply using species richness.
these techniques commonly used is the Fluctuating Asymmetry (FA). In this study, we explore the effects of riparian vegetation removal on the levels of FA on hind wings traits of Erythrodiplax basalis (Kirby). The results showed that traits present normal distribution and zero mean, which allows us to assume that observe levels of asymmetry are FA. It was also evident that FA indexes are not correlated to the wing length, and present low levels of measurement error. There is no significantly evidence of increase in the FA levels in degraded areas in comparison with preserved areas for the
measured variables (wing length, wing width on the nodus level, distance between triangle and nodus and distance between anal loop and nodus). The hypothesis that individuals collected in altered areas present higher levels of FA in wing traits was not corroborated. This may result from the fact that E. basalis is a species with good dispersal capability, and the specimens sampled in disturbed areas may have developed elsewhere and were only using the areas as a point of foraging and therefore was not detected AF. Another factor that corroborates this prediction is the fact that other studies using Zygoptera species that have lower dispersal ability, significant levels of physical activities has been detected.
of organisms will be smaller in environments with low integrity, and that many species are specific to preserved environments, disappearing from impacted environments, and also characteristic species of altered environments.
the Amazonian diversity with special place for the theory of isolation by rivers and a set of
hypothesis related to contemporary environmental dissimilarity. We explore those
hypotheses here using the biogeographic distributional patterns of dragonflies in interfluve
areas of the Amazonian biome and also evaluate how differences among in dispersal
capabilities between the Anisoptera and Zygoptera suborders may contribute to those
patterns. We used distributional information of 392 odonate species in the Amazonian
forest in a cladistic analysis of distributions and endemism and the estimated faunistic
similarity among interfluves with the Sorensen index. The environmental similarity among
interfluves was analysed by discriminant analysis based on eight environmental metrics.
Different metrics for geographic distance (connectivity) among interfluves were evaluated
and their relation to the other variables tested by the Mantel test. The number of endemic
species was linearly correlated to the area of the interfluves. General endemism patterns
showed consistent resemblance to those reported for vertebrates, especially the similarity
among the Rondoˆnia and Inambari interfluves. Geographical distance has no predictive
value for dragonflies distribution, but the environmental similarity is a good predictor of
proportion of shared species. The low dispersal group (Zygoptera) presented more clear
patterns of distribution and a lower proportion of shared species among different interfluves.
The environmental similarity can be considered the determinant factor of the distribution
of dragonflies, possibly due to environmental specificity evolved during a long
history of some clades in this system. The low dispersal group (Zygoptera) retained more biogeographical information about possible historical factors that determine current
distribution. Also, the transport of larvae by macrophyte banks, the lateral change of river
courses, the reversal of the drainage basin, together with the capacity to disperse across
rivers for some species may be explanations for the lack of effect of isolation by rivers,
especially for Anisoptera.
environments. Species richness was different between sites, being greater in disturbed habitats. Total abundance was higher among preserved and altered environments, and differed significantly from the degraded areas. The NMDS analysis indicates that, in preserved and modified sites, the similarity in the composition of species differs from degraded areas. Four species showed a positive relationship with increasing values of HII. Baetidae showed environmental indicator species with different levels of preservation, with Zelusia principalis Lugo-Ortiz &
McCafferty, 1998 and Baetodes sp. being indicators of preserved environments and Aturbina nigra Salles, Boldrini & Shimano, 2011, Callibaetis sp. 2, Camelobaetidius aff. janae, Paracloeodes binodulus Lugo-Ortiz & McCafferty, 1996 and Waltzoyphius roberti Thomas & Peru, 2002 as indicators of modified environments. The knowledge on the ecology of species advances in terms of providing subsidies for the biomonitoring of
basins and the use of indicator species.
abdominal color patterns in a pond of Goiás.In July 2010 we collected 12 specimens of Erythrodiplax fusca in Samambaia lake in Goiânia-GO. Of these specimens, five presented with abdominal blue pattern and seven with red pattern. This work is a record of sympatric occurrence of both forms in a pond in central-western Brazil.
The results of this study show that the physic structure of aquatic environments affect species composition. In that way, retreat
of riparian vegetation and streams dam up can take significant losses in the diversity.
four times for the width between the nodus and proximal
portion of the pterostigma of forewings (FW), two times for the width of the wing in the region of nodus of FW, and approximately 1.7 times for the number of postnodal cells of FW. The increase is almost five times for the width between the nodus and the proximal portion of the pterostigma of hind wings (HW), three times for the number of postnodal cells of HW, and approximately 1.6 times the width between quadrangle and nodus of HW. Individuals of preserved sites were nearly 3.3% larger than for degraded sites, based on mean hind wing length. Our results supports that the development of A. tinctipennis in degraded
areas is affected by riparian vegetation removal and may reflect in wing FA variations. Consequently, these FA measures may be a useful tool for bioassessment using Odonata insects as a model.
sparsum (n = 370). There has been loss of species richness in impacted, large and lentic environments. Composition variations related to the flow, the vegetation type and the interaction between conservation levels and flow was detected. Conservation levels, width and the quantitative habitat integrity index (HII) did not influence the Trichoptera composition. These results may encourage further investigation of impact effects on aquatic
insect compositions and pattern of distribution in the transition area between the Cerrado and the Amazonian Forest.
system. Here, we evaluated the effects of forest fragmentation and forest cover changes on habitat characteristics of streamlets (igarape´s) in Amazonian forests and on the aquatic insect communities found there.Wealso developed a habitat integrity index (HII) based on Petersen’s protocol (1992) to evaluate
physical integrity of these streamlets and to determine its efficiency to interpret the environmental impacts on this system. We studied 20 small streams at the Biological Dynamics of Forest Fragments Project (BDFFP INPA/SI) study areas, Central Amazonia, 80 km north of Manaus, Amazonas State, Brazil. The
vegetation cover was estimated by using LANDSAT images and classified in the following categories: exposed soil, pastures, secondary forests (capoeiras), and primary forests. Stream habitat features were evaluated by using a HII based on visual assessment of local characteristics. Aquatic insects were sampled in four major stream substrates: litter deposited in pools
or backwaters, litter retained in riffles, sand, and marginal banks. Stream habitat characteristics were significantly correlated to land use and riparian forest condition. Overall aquatic insect richness and Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness were significantly lower in pasture streams, and their
taxonomic composition differed significantly from streams in forested areas. However, these metrics were not significantly correlated to the stream HII. Taxonomic composition of bank insect assemblages changed significantly between streams with low and high values of HII. There was no significant relationship
between the proportion of primary forest cover and the faunal metrics. Only drastic changes in the vegetal cover seem to induce significant changes in the aquatic insect community. Matrix habitat heterogeneity, distance to forest fragments, the presence of areas of secondary forest, and the intrinsic capacity to
disperse in many of the insect groups may have contributed to attenuate the effects of habitat disturbance on aquatic insect assemblages in streamlets.
properties along the river, and also that potamal areas of the river are similar to lakes. In rivers with periodic floods we also expect a high degree of similarity due to increased environmental
similarity and increase dispersal of component species. Otherwise, rivers must be conceived as a landscape element with an intrinsic hierarchical nature and dispersal among its parts are constrained by this structure. Under this view, we also could expect that different basin or different ‘‘micro-basin’’ could present communities that are historically different in their general properties. Here, we aimed to describe odonate larval
communities in the Pantanal Mortes-Araguaia river basin in Brazil comparing the composition, species richness and community structure between lakes and rivers, and also the possible
differences among river basins. The field work was done in three rivers and three lakes chosen to conform to a paired experiment, each pair in a different river basin. An aggregated sampling unit
was used based on Ekman dredge and D-nets replicated on each site. We sampled 936 individuals distributed in 30 genera and a total of 34 morphotypes. There was no difference in species
richness among lakes and rivers, but a marked difference among basins. Samples from the same basin present a higher similarity of the species abundance relations than among river or lake
samples. We also did not observed differences in composition and community structure between large rivers and lakes, in the same basin. The results supported the concept of structural similarity
between large rivers and lakes and the differences observed among basins could indicate historical events in colonization that are shaping communities characteristics.
the relative importance of local environmental conditions and regional dispersal limitation to determine beta-diversity and distributional patterns of species richness of the adult Odonata assemblage present in the Adolpho Ducke Forest Reserve (Manaus, Amazon) river basins.
2. Samples were taken in 24 streamlets distributed in four river sub-basins (pairwise distances up to 10 km) during the rainy season. The samples consisted of visual surveys for adult individuals of Odonata present in 100 m transects along each
streamlet; each transect was divided into 20 segments of 5 m.
3. A total of 17 species were observed and 23 (4.8) were estimated using a jackknife procedure. Four sub-basins were statistically similar based on species richness and beta-diversity. Distance among the streamlets had a low predictive power for species richness, while beta-diversity patterns were mainly explained by local environmental variables (channel width and depth). The low values of the beta-diversity index may be attributed to the high similarity of the environment, which presented little variation in abiotic conditions.
4. Low dispersal constraints and environmental stability are the primary explanations for low beta-diversity at this spatial extension. Nevertheless, the importance of local environmental variables to determine beta-diversity suggests its inclusion as criteria for setting conservation priorities for this group.