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The rare genus Leptofoenus Smith, 1862 (Hymenoptera: Pteromalidae, Leptofoeninae): new records, and aspects of its distribution
Get PDFDespite being the largest and most remarkable species of Chalcidoidea, species of Leptofoeninae are very rarely collected. Here, we expand the distribution range extension of the Leptofoenus howardi (Ashmead, 1895) for Rondônia and Minas Gerais, Leptofoenus stephanoides (Roman, 1920) for Rondônia, Espírito Santo and São Paulo and Leptofoenus westwoodi (Ashmead, 1895) for Roraima, Amazonas, Rondônia, Bahia, Minas Gerais, Rio de Janeiro and Rio Grande do Sul
Gyrinus rhyssonotum sp. N., a new species of Gyrinidae (Coleoptera: Adephaga) from northern Brazil
No full textGyrinus rhyssonotum sp. n. is described and illustrated based on adult males and females collected in Barcelos County, Amazonas state, Brazil. The new species belongs to the subgenus Oreogyrinus Ochs, 1935 and it is compared with Gyrinus (Oreogyrinus) fittkaui Ochs, 1963 and G. (O.) opalinus Régimbart, 1883, both occurring in the Brazilian Amazonas and G. (O.) colombicus Régimbart, 1883 and G. (O.) venezolensis Ochs, 1954, these two latter alien to the Brazilian fauna but with which G. (O) rhyssonotum sp. n. seems to be more closely related, though the new species can be distinguished from both by a series of characteristics, mainly observed in the body shape, elytra, pronotum, and in male and female genitalia. Copyright © 2019 Magnolia Press
Efeitos da alteração ambiental sobre Bryconops giacopinii (Characidae) em igarapés de terra firme: dieta, fator de condição, parasitismo e reprodução
Get PDFChanges in aquatic environments trigger several effects on organisms, especially for fish. These effects can be observed in changes in the dynamics of resource availability, as well as the occurrence of unusual organisms in the natural environment, which in turn, affect the body state and compromise the fitness of individuals. The present study compared biological and parasitological parameters among populations of Bryconops giacopinii (Fernandez-Yépez, 1950) (Characiforms: Characidae) sampled in intact forest streams belonging to the Adolpho Ducke Forest Reserve and in altered streams by damming caused by the construction of the BR-174 highway. Dietary results showed predominance of allochthonous insects in the samples sampled from the intact forest streams, while the specimens obtained in the altered streams consumed larger proportions of autochthonous foods, with the predominance of detritus. The relative condition factor (Kn) was higher for the populations in intact forest streams. Digenetic parasites and nematodes occurred with much greater frequency and abundance in specimens of altered forest streams. There was a significant, but weak, relationship between parasitic abundance and condition factor in B. giacopinii populations from altered streams by BR-174. The fecundity (absolute and relative) of the females was significantly higher among the specimens, besides the occurrence of a positive and significant relationship between the fecundity and the size of the females only from altered streams. On the other hand, there was no difference in oocyte diameter among populations sampled in both types of environments. However, there is an indication of differences in the type of spawning among the populations of the evaluated environments. These results indicate that the changes caused by damming, had a significant influence on some biological and ecological parameters of the local populations of B. giacopinii, being observed the potential of adaptability of the individuals to the impacts generated in the environment. The observed differences indicate that the negative effects of damming are not homogeneous for the various biological aspects measured in the populations that occupy the altered streams by BR-174 highway.Alterações em ambientes aquáticos desencadeiam uma série de efeitos sobre os organismos, em especial aos os peixes. Esses efeitos podem ser observados em mudanças na dinâmica de disponibilidade de recursos, bem como da ocorrência de organismos incomuns em ambiente natural, que por sua vez, afetam o estado corporal e comprometem o fitness dos indivíduos. O presente estudo comparou parâmetros biológicos e parasitológicos entre populações de Bryconops giacopinii (Fernandez-Yépez, 1950) (Characiformes: Characidae) amostradas em igarapés íntegros pertencentes a Reserva Florestal Adolpho Ducke e em igarapés alterados pelo represamento causado pela construção da rodovia BR-174. Os resultados referentes à dieta apresentaram predomínio de insetos alóctones nos exemplares amostrados nos igarapés íntegros, enquanto os exemplares obtidos nos igarapés alterados consumiram proporções maiores de alimentos autóctones, com a predominância de detrito. O fator de condição alométrico (Kn) foi superior para as populações em igarapés íntegros. Parasitos digenéticos e nematódeos ocorreram com frequência e abundância muito maiores nos exemplares de igarapés alterados. Houve uma relação significativa negativa, porém, fraca entre a abundância parasitária e o fator de condição nas populações de B. giacopinii nos igarapés alterados. A fecundidade (absoluta e relativa) das fêmeas foi significativamente mais alta entre os exemplares, além da ocorrência de relação positiva e significativa entre a fecundidade e o tamanho das fêmeas apenas nos igarapés alterados. Por outro lado, não houve diferença no diâmetro dos ovócitos entre as populações amostradas nos dois tipos de ambientes. Porém há um indicativo de diferenças no tipo de desova entre as populações dos ambientes avaliados. Estes resultados indicam que as alterações causadas pelo represamento influenciaram significativamente alguns parâmetros biológicos e ecológicos das populações de B. giacopinii presentes na BR-174, sendo observado o potencial de adaptabilidade dos indivíduos frente aos impactos gerados no ambiente. As diferenças observadas indicam que os efeitos negativos do represamento não são homogêneos para os diversos aspectos biológicos mensurados nas populações que ocupam os igarapés alterados pela rodovia BR-174
New Limonoids from Dictyoloma vandellianum and Sohnreyia excelsa: Chemosystematic considerations
Get PDFMolecular phylogenetic studies separated and united a group of genera that constituted the Spathelia-Ptaeroxylon clade, in which Dictyoloma and Sohnreyia have been included. Our taxonomic interest in the Dictyoloma vandellianum and Sohnreyia excelsa stimulated an investigation of both species searching for limonoids. Leaves from D. vandellianum afforded the new limonoid 1,2-dihydro-1α-hydroxy-8,30-epoxy-cneorin R, and heartwood yielded the new rearranged limonoid dictyolomin. Leaves from S. excelsa afforded the new protolimonoid 3β-angeloyloxy-7α,24,25-trihydroxy-21,23-oxide-14,18-cycloapotirucall-21-methoxycetal and the new cycloheptanyl ring C limonoid with carbonate substituent and named as sohnreyolide. The new limonoids from Sohnreyia and Dictyoloma show similarities with those from Rutaceae and Meliaceae, providing support for moving Spathelia-Ptaeroxylon clade near to these associated large families. ©2019 Sociedade Brasileira de Química
Variação espacial de atributos químicos em terra preta arqueológica sob cultivo de cacau na amazonia ocidental
Get PDFArcheological Dark Earths (ADEs) are fertility soils that are notoriously superior to the vast majority of soils typical of the Amazon region. The study on ADEs has intensified due to the good characteristics presented by these soils, such as high concentration of nutrients (phosphorus, calcium, magnesium). In this sense, the aim of this study was to evaluate the spatial distribution of soil chemical attributes in an area of black archeological earth soil under cocoa cultivation in the municipality of Apuí (AM). The mapping of a 42 x 88 m mesh, with irregular spacing of 6 x 8 m, totaling 88 points, was carried out, and then soil samples were collected at depths of 0.0-0.05; 0.05-0.10; (pH, O.C, Sto C, (H+Al), P, K, Ca, Mg, SB, CEC and V%). Data were analyzed using descriptive and geostatistical statistics techniques. The mean and median values were adjusted to the near values, indicating normal distribution, while the soil chemical attributes were adjusted to the spherical and exponential semivariograms models. The majority of the attributes presented coefficient of variation (CV) between 12.1 and 60%, characterized as average variability, the variables in the study presented different ranges and most of them had a strong spatial dependence. The geostatistical techniques used allowed the adjustments of the theoretical models that best represented the experimental semivariance, thus enabling the construction of thematic maps of the spatial distribution of the values of the attributes of the studied area. © 2019, Universidade Federal de Uberlandia. All rights reserved
Caracterização da cadeia produtiva de brássicas no Brasil
Get PDFBrassica crops worldwide provide the greatest diversity of products used by man derived from a single genus. Collectively, leafy, flower and root vegetables can be eaten fresh, cooked and processed. The production of these vegetables in Brazil has been growing exponentially in the last decades, due to its economic importance, with major production volumes in several states and a quick monetary return for growers in areas considered of small acreage. With expansion, a number of aspects, including demands for quality and safety of these foods introduce themselves, strictly attached to the forms of production, logistics and their appearance. To meet the challenges and list the trends within the activities of different agents, a multiple case study was held in the states of Amazon, Minas Gerais, Paraná and Rio de Janeiro. Altogether, 55 stakeholders were interviewed, along with the compilation of different sources of data to characterize this productive chain. Changes in the scenario are imperative in order to maintain the activity of overcoming years, being related to cultivars adaptation, plant health, productions costs and difficulties during the establishment of crops. To overcome these adversities, a collective effort in terms of organization, technology transfer and R&D from official and private agents, technical assistance, and regional sanitary inspection is imperative, aiming, especially, in actions regarding themes like protected cultivation, mechanization/automation and adding value to products by processing and packaging, listed by stakeholders as priority. © 2019, Sociedade de Olericultura do Brasil. All rights reserved
Description of a new Hemigrammus Gill (Characiformes: Characidae) from the río Madeira basin in Peru and Bolivia
No full textWe described herein a new Hemigrammus from the río Madre de Dios and rio Mamoré basins in southeastern Peru and Bolivia. The new species possess a color pattern similar to those belonging to the Hemigrammus lunatus species-group, i.e., a broad longitudinal dark stripe across the eye and a conspicuous, narrow dark stripe along the anal-fin basis. It can be easily diagnosed from the species belonging to this group by presenting the combination of the following characters: an oval, horizontally elongated humeral blotch, 6-7 upper branch and 10-12 lower branch gill-rakers, up to five cusps on broader maxillary teeth, and by lacking a midlateral dark stripe. Comments on its putative relationships are provided. Additionally, we updated the geographical distribution of Hemigrammus lunatus and H. machadoi based on an exhaustive survey of material deposited in collections. [Species Zoobank registration: urn:lsid:zoobank.org:act:A2ED5D61-8434- 4A0F-BC5B-B496FB3DC191]. Copyright © 2019 Magnolia Press
Analise de proteína de estresse térmico em Aedes aegypti Linnaeus, 1762 (Diptera: Culicidae), mantido em microcosmos, simulando as condições climáticas para o 2100
No full textLength-weight relationships of five fish species from lakes of the Central Amazonian floodplains
No full textParameters of the length-weight relationship (LWR) were calculated for five fish species from Amazon Basin. Samplings were carried out in ten lakes of the Solimões River floodplains during the four seasons of the hydrological cycle: rising water, high water, receding water, and low water, during two periods. The first period of eight years included samplings performed from 2001 to 2008 and the second sampling period of two years was from 2012 to 2013. Specimens were captured using gillnets (mesh sizes ranging from 30 to 120 mm between opposite knots) and standardized dimension of 20 m in length × 2 m in height. This study provides the LWR parameters for Acarichthys heckelii, Leporinus trifasciatus, Brycon amazonicus, Curimatella meyeri and Osteoglossum bicirrhosum. © 2019 Blackwell Verlag Gmb