924 resultados para Ephemeroptera, Plecoptera and Tricoptera taxa


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A catalogue is provided with the type material of four superfamilies of "Acalyptrate" (Conopoidea, Diopsoidea, Nerioidea and Tephritoidea) held in the collection of the Museu de Zoologia da Universidade de São Paulo (MZUSP), São Paulo, Brazil. Concerning the taxa dealt with herein, the Diptera collection of MZUSP held 77 holotypes, 4 "allotypes" and 194 paratypes. In this paper, information about data labels, preservation and missing structures of the type specimens is given.

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Phylogeny and revision of the bee genus Rhinocorynura Schrottky (Hymenoptera, Apidae, Augochlorini), with comments on its female cephalic polymorphism. A taxonomic revision and a phylogeny for the species of Rhinocorynura are provided. Six species are recognized: R. briseis, R. crotonis, R. inflaticeps and R. vernoniae stat. nov., the latter removed from synonymy with R. inflaticeps, in addition to two newly described species, R. brunnea sp. nov. and R. viridis sp. nov. Lectotypes for Halictus crotonis Ducke, 1906 and Halictus inflaticeps Ducke, 1906 are hereby designated. Another available name included in Rhinocorynura, Corynuropsis ashmeadi Schrottky, 1909, is removed from the genus and treated as species inquerenda in Augochlorini. Rhinocorynura is monophyletic in the phylogenetic analysis and the following relationships were found among its species: (R. crotonis (R. briseis ((R. brunnea sp. nov. + R. viridis sp. nov.) (R. inflaticeps + R. vernoniae)))). Biogeographic relationships within the genus and comparisons with related taxa are presented. Females of all species exhibit pronounced variation in body size, in two of them, R. inflaticeps and R. vernoniae, with structural modifications possibly linked to division of labor. Identification key and illustrations for the species are provided.

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Partial DNA sequences from two mitochondrial (mt) and one nuclear gene (cytochrome b, 12S rRNA, and C-mos) were used to estimate the phylogenetic relationships among the six extant species of skinks endemic to the Cape Verde Archipelago. The species form a monophyletic unit, indicating a single colonization of the islands, probably from West Africa. Mabuya vaillanti and M. delalandii are sister taxa, as indicated by morphological characters. Mabuya fogoensis and M. stangeri are closely related, but the former is probably paraphyletic. Mabuya spinalis and M. salensis are also probably paraphyletic. Within species, samples from separate islands always form monophyletic groups. Some colonization events can be hypothesized, which are in line with the age of the islands. C-mos variation is concordant with the topology derived from mtDNA.

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The first list of the species of Ephemeroptera from Pernambuco State, Northeastern Brazil, is presented. The survey was based on collections from numerous rivers and streams of 17 counties. A total of five families, 28 genera, and 38 species were recorded, including 22 genera and 31 species newly recorded from Pernambuco State. Moreover, Farrodes tepui Domínguez, Molineri & Peters, 1996, Lisetta ernsti Thomas & Dominique, 2005, and Simothraulopsis (Maculognathus) sabalo Kluge, 2007 are recorded for the first time to Brazil.

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Study of the mayfly order Ephemeroptera (Insecta) in Brazil: a scienciometric review. Despite an increase in the number of studies in recent years of the aquatic insect order Ephemeroptera (the mayflies) much still remains to be learnt. In order to identify the current state of knowledge of this group in Brazil, we performed a scienciometric analysis with the purpose of identifying the strong and weak points of Brazilian research into the group. Our research used the "Institute for Scientific Information - ISI" database and was based on the abstracts, titles and keywords of manuscripts published between 1992 and 2011. We selected the papers with the combination of the words "Ephemeroptera" and "Brazil*" based on a search in February 2012. We analyzed 92 articles, and noted a lack of studies in some Brazilian states, no specific studies about some families, and an absence of phylogenetic studies. To improve ecological studies, it is necessary to fine-tune taxonomic resolution. Moreover, there is a lack of studies investigating the environmental variables which influence the distribution of mayflies. Despite these gaps, if the rate of publication with mayflies proceeds at the same pace, we anticipate that many of these knowledge gaps will be closed.

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PREMISE OF THE STUDY: Numerous long-term studies in seasonal habitats have tracked interannual variation in first flowering date (FFD) in relation to climate, documenting the effect of warming on the FFD of many species. Despite these efforts, long-term phenological observations are still lacking for many species. If we could forecast responses based on taxonomic affinity, however, then we could leverage existing data to predict the climate-related phenological shifts of many taxa not yet studied. METHODS: We examined phenological time series of 1226 species occurrences (1031 unique species in 119 families) across seven sites in North America and England to determine whether family membership (or family mean FFD) predicts the sensitivity of FFD to standardized interannual changes in temperature and precipitation during seasonal periods before flowering and whether families differ significantly in the direction of their phenological shifts. KEY RESULTS: Patterns observed among species within and across sites are mirrored among family means across sites; early-flowering families advance their FFD in response to warming more than late-flowering families. By contrast, we found no consistent relationships among taxa between mean FFD and sensitivity to precipitation as measured here. CONCLUSIONS: Family membership can be used to identify taxa of high and low sensitivity to temperature within the seasonal, temperate zone plant communities analyzed here. The high sensitivity of early-flowering families (and the absence of early-flowering families not sensitive to temperature) may reflect plasticity in flowering time, which may be adaptive in environments where early-season conditions are highly variable among years.

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The distribution patterns of benthic algal assemblages in the Tinto, Odiel and Piedras rivers were analyzed during the winter of 2005 in 18 sampling stations. The main objective was to assess and compare the algal communities and parameters affecting them both in the zones affected by acid mine drainage (AMD) and in naturally alkaline waters. A total of 108 benthic diatom taxa and 31 non-diatom taxa were identi ed. Results showed large differences between algal communities in the two environments: Pinnularia acoricola, P. subcapitata and Eunotia exigua were the most frequent diatom taxa in regions affected by acid mine drainage, along with algae like Klebsormidium and Euglena mutabilis were the most relevant non-diatom taxa. In alkaline waters the dominant diatom taxa were Planothidium frequentissimum, Gomphonema angustum, Fragilaria capucina, and some species of Navicula (N. viridula, N. veneta or N. radiosa), accompanied by Oscillatoria and Anabaena as well as by streptophytes of the group of zygnemataceae and desmidiaceae

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Conservation of mayflies (Insecta, Ephemeroptera) in Espírito Santo, southeastern Brazil. Ephemeroptera exhibits great diversity among bodies of freshwater in the Atlantic Forest, a biome that is suffering from massive human impact. Within this context, the creation of conservation units using biological information is more recommended than economic, cultural, or political criteria. The distribution pattern of 76 Ephemeroptera species was analyzed using the biogeographical methods Parsimony Analysis of Endemicity and Network Analysis Method in order to infer relevant areas for conservation of the mayfly community in Espírito Santo. The results obtained from both analyses were largely congruent, and pointed out four relevant areas for conservation: two in the south of the state, where conservation units or priority areas for conservation are well established; and two in the north, a region in the state where little conservation efforts have been historically done. Therefore, based on our analyses on mayflies, we recommend the expansion of the existing APCs or the creation of new APCs on the north of Espírito Santo.

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The study of organisms and their resources is critical to further understanding population dynamics in space and time. Although drosophilids have been widely used as biological models, their relationship with breeding and feeding sites has received little attention. Here, we investigate drosophilids breeding in fruits in the Brazilian Savanna, in two contrasting vegetation types, throughout 16 months. Specifically, larval assemblages were compared between savannas and forests, as well as between rainy and dry seasons. The relationships between resource availability and drosophilid abundance and richness were also tested. The community (4,022 drosophilids of 23 species and 2,496 fruits of 57 plant taxa) varied widely in space and time. Drosophilid assemblages experienced a strong bottleneck during the dry season, decreasing to only 0.5% of the abundance of the rainy season. Additionally, savannas displayed lower richness and higher abundance than the forests, and were dominated by exotic species. Both differences in larval assemblages throughout the year and between savannas and gallery forests are consistent with those previously seen in adults. Although the causes of this dynamic are clearly multifactorial, resource availability (richness and abundance of rotten fruits) was a good predictor of the fly assemblage structure.

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ABSTRACTThis study reviewed the data on the Brazilian Ephemeroptera, based on the studies published before July, 2013, estimated the number of species still to be described, and identified which regions of the country have been the subject of least research. More than half the species are known from the description of only one developmental stage, with imagoes being described more frequently than nymphs. The Brazilian Northeast is the region with the weakest database. Body size affected description rates, with a strong tendency for the larger species to be described first. The estimated number of unknown Brazilian species was accentuated by the fact that so few species have been described so far. The steep slope of the asymptote and the considerable confidence interval of the estimate reinforce the conclusion that a large number of species are still to be described. This emphasizes the need for investments in the training of specialists in systematics and ecology for all regions of Brazil to correct these deficiencies, given the role of published papers as a primary source of information, and the fundamental importance of taxonomic knowledge for the development of effective measures for the conservation of ephemeropteran and the aquatic ecosystems they depend on.

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ABSTRACTIn order to expand the knowledge on the composition of Ephemeroptera from large rivers, we present, herein, the first survey of mayflies from the São Mateus River Basin, Espírito Santo State. Adults were collected biannually in 2012 and 2013 with the aid of Pennsylvania light trap in eleven points distributed in the main river of the river basin, São Mateus River and its two main tributaries, Cotaxé River (Braço Norte) and Cricaré River (Braço Sul). Thirty-three species were identified (22 nominal and 11 morphospecies) in 24 genera and five families. One genus and one species are reported for the first time from Brazil, three species from Southeastern Region of Brazil, and two species from the state. Five species and one genus not previously described were also found. Moreover, around 20% of the known species of mayfly registered from the state were found. This work reinforces the need to give more attention to research on large rivers due to the high potential for diversity, not only for Ephemeroptera, but also for other aquatic insects.

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ABSTRACT A detailed protocol for chemical clearing of bee specimens is presented. Dry specimens as well as those preserved in liquid media can be cleared using this protocol. The procedure consists of a combined use of alkaline solution (KOH or NaOH) and hydrogen peroxide (H2O2), followed by the boiling of the cleared specimens in 60–70% EtOH. Clearing is particularly useful for internal skeletal morphological research. This procedure allows for efficient study of internal projections of the exoskeleton (e.g., apodemes, furcae, phragmata, tentoria, internal ridges and sulci), but this process makes external features of the integument, as some sutures and sulci, readily available for observation as well. Upon completion of the chemical clearing process the specimens can be stored in glycerin. This procedure was developed and evaluated for the preparation of bees and other Apoidea, but modifications for use with other insect taxa should be straightforward after some experimentation on variations of timing of steps, concentration of solutions, temperatures, and the necessity of a given step. Comments on the long-term storage, morphological examination, and photodocumentation of cleared specimens are also provided.

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This editorial examines the actions undertaken in number 5 and announces two important changes for the numbers 6 and 7, namely frequency and languages. Furthermore, the use of some bibliometric indicators, such as impact factor and refusal rate, is critically analyzed.

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ABSTRACT The role of chromosomal rearrangements in the speciation process is much debated and many theoretical models have been developed. The shrews of the Sorex araneus group offer extraordinary opportunities to study the relationship between chromosomal variation and speciation. Indeed, this group of morphologically very similar species received a great deal of attention due to its karyotypic variability, which is mainly attributed to Robertsonian fusions. To explore the impact of karyotypic changes on genetic differentiation, we first studied the relationship between genetic and karyotypic structure among Alpine species and among chromosome races of the S. araneus group using Bayesian admixture analyses. The results of these analyses confirmed the taxonomic status of the studied species even though introgression can still be detected between species. Moreover, the strong spatial sub-structure highlighted the role of historical factors (e.g. geographical isolation) on genetic structure. Next, we studied gene flow at the chromosome level to address the question of the impact of chromosomal rearrangements on genetic differentiation. We used flow sorted chromosomes from three different karyotypic taxa of the S. araneus group to map microsatellite markers at the chromosóme arm level. We have been able to map 24 markers and to show that the karyotypic organisation of these taxa is well conserved, which suggests that these markers can be used for further inter-taxa studies. A general prediction of chromosomal speciation models is that genetic differentiation between two taxa should be larger across rearranged chromosomes than across chromosomes common to both taxa. We combined two approaches using mapped microsatellites to test this prediction. First, we studied the genetic differentiation among five shrew taxa placed at different evolutionary levels (i.e. within and among species). In this large scale study, we detected an overall significant difference in genetic structure between rearranged vs. common chromosomes. Moreover, this effect varied among pairwise comparisons, which allowed us to differentiate the role of the karyotypic complexity of hybrids and of the evolutionary divergence between taxa. Secondly, we compared the levels of gene flow measured across common vs. rearranged chromosomes in two karyotypically different hybrid zones (strong vs. low complexity of hybrids), which show similar levels of genetic structure. We detected a significantly stronger genetic structure across rearranged chromosomes in the hybrid zone showing the highest level of hybrid complexity. The large variance observed among loci suggested that other factors, such as the position of markers within the chromosome, also certainly affects genetic structure. In conclusion, our results strongly support the role of chromosomal rearrangements in the reproductive barrier and suggest their importance in speciation process of the S. araneus group. RESUME Le rôle des réarrangements chromosomiques dans les processus de spéciation est fortement débattu et de nombreux modèles théoriques ont été développés sur le sujet. Les musaraignes du groupe Sorex araneus présentent de nombreuses opportunités pour étudier les relations entre les variations chromosomiques et la spéciation. En effet, ce groupe d'espèces morphologiquement très proches a attiré l'attention des chercheurs en raison de sa variabilité caryotypique principalement attribuée à des fusions Robertsoniennes. Pour explorer l'impact des changements caryotypiques sur la différenciation génétique, nous avons tout d'abord étudié les relations entre la structure génétique et caryotypique de races chromosomiques et d'espèces alpine du groupe S. araneus en utilisant des analyses Bayesiennes d' « admixture ». Les résultats de ces analyses ont confirmé le statut taxonomique des espèces étudiées bien que nous ayons détecté de l'introgression entre espèces. L'observation d'une sous structure spatiale relativement forte souligne l'importance des facteurs historiques (telle que l'isolation géographique) sur la structure génétique de ce groupe. Ensuite, nous avons étudié le flux de gène au niveau des chromosomes pour aborder de manière directe la question de l'impact des réarrangements chromosomiques sur la différenciation génétique. En conséquence, nous avons utilisé des tris de chromosomes de trois taxons du groupe S. araneus pour localiser des marqueurs microsatellites au niveau du bras chromosomique. Au cours de cette étude, nous avons pu localiser 24 marqueurs et montrer une forte conservation dans l'organisation du caryotype de ces taxa. Ce résultat suggère que leur utilisation est appropriée pour des études entre taxa. Une prédiction générale à tous les modèles de spéciation chromosomique correspond à la plus grande différenciation génétique des chromosomes réarrangés que des chromosomes communs. Nous avons combiné deux approches utilisant des microsatellites localisés au niveau du bras chromosomique pour tester cette prédiction. Premièrement, nous avons étudié la différenciation génétique entre cinq taxa du groupe S. araneus se trouvant à des niveaux évolutifs différents (i.e. à l'intérieur et entre espèce). Au cours de cette étude, nous avons détecté une différenciation globale significativement plus élevée sur les chromosomes réarrangés. Cet effet varie entre les comparaisons, ce qui nous a permis de souligner le rôle de la complexité caryotypique des hybrides et du niveau de divergence évolutive entre taxa. Deuxièmement, nous avons comparé le flux de gènes des chromosomes communs et réarrangés dans deux zones d'hybridation caryotypiquement différentes (forte vs. Faible complexité des hybrides) mais présentant un niveau de différenciation génétique similaire. Ceci nous a permis de détecter une structure génétique significativement plus élevée sur les chromosomes réarrangés au centre de la zone d'hybridation présentant la plus grande complexité caryotypic. La forte variance observée entre loci souligne en outre le fait que d'autres facteurs, tel que la position du marqueur sur le chromosome, affectent probablement aussi la structure génétique mesurée. En conclusion, nos résultats supportent fortement le rôle des réarrangements chromosomiques dans la barrière reproductive entre espèces ainsi que leur importance dans les processus de spéciation des musaraignes du groupe S. araneus.

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Previous studies have shown that arbuscular mycorrhizal fungi (AMF) can influence plant diversity and ecosystem productivity. However, little is known about the effects of AMF and different AMF taxa on other important community properties such as nutrient acquisition, plant survival and soil structure. We established experimental grassland microcosms and tested the impact of AMF and of different AMF taxa on a number of grassland characteristics. We also tested whether plant species benefited from the same or different AMF taxa in subsequent growing seasons. AMF enhanced phosphorus acquisition, soil aggregation and survival of several plant species, but AMF did not increase total plant productivity. Moreover, AMF increased nitrogen acquisition by some plant species, but AMF had no effect on total N uptake by the plant community. Plant growth responses to AMF were temporally variable and some plant species obtained the highest biomass with different AMF in different years. Hence the results indicate that it may be beneficial for a plant to be colonized by different AMF taxa in different seasons. This study shows that AMF play a key role in grassland by improving plant nutrition and soil structure, and by regulating the make-up of the plant community.