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The lizards along the road BR-319 in the Purus-Madeira interfluve, Brazilian Amazonia (Squamata, Lacertilia)
Get PDFHere we present data on the identity and geographic distribution of lizard taxa in the Purus-Madeira interfluve, along the road BR-319 in Brazilian Amazonia. We sampled 10 modules located at least 40 kilometres from each other. Data collection was performed through active search on vegetation and leaf-litter along 250 m-long transects, and by occasional encounters. Twenty-five taxa from 16 genera and eight families were recorded. The present assessment reinforces the importance of this area to the conservation of Amazonian lizards and should be considered as basis for studies of ecology and environmental impact regarding lizard communities in this threatened region. © 2019, Societas Europaea Herpetologica. All rights reserved
Morphology and bionomy of immature stages and description of the adult male of Catachlorops (C.) rufescens (Fabricius, 1805) (Diptera: Tabanidae) from the Central Amazon, Brazil
No full textLarvae of Catachlorops (C.) rufescens (Fabricius) were sampled in streams in the municipalities of Iranduba, Manacapuru, Manaus, Novo Airão, Presidente Figueiredo, and Rio Preto da Eva in the state of Amazonas, Brazil. Sampling was conducted in 2002 and between July 2007 and October 2008. Larvae were found entangled in sand on the underwater roots of riparian vegetation. A total of 169 larvae were collected, from which 93 were reared to obtain 64 imagoes (33 males and 31 females). The larval and pupal stages lasted an average of 88.2 days (±64.7) and 12.6 days (±2.9), respectively. A total of sixteen larval instars were estimated according to Dyar's Law. The larva, pupa and adult male were described, while bionomic data were provided for the larval stage under natural and controlled environmental conditions. © 2018 Elsevier Gmb
Sedimentary Transport Influences on Diagenetic Processes at the Amazon Continental Shelf, Brazil
No full textA new species of macrostemum kolenati, 1859 from brazilian amazon and the immature stages of m. Brasiliense (fischer, 1970) (trichoptera: Hydropsychidae)
Get PDFMacrostemum is the second largest genus of Macronematinae with about 104 described species distributed in the Neotropical (18), Afrotropical (20), Australasian (7), Palearctic (2), Nearctic (3) and Oriental (54) regions. Despite its great diversity, knowledge about its immature stages is scarce: worldwide, only 7 species (6.7%) have larvae and/or pupae described. From the Neotropics, only one species, Macrostemum ulmeri (Banks, 1913), has described larvae and pupae. The objectives of this study are to describe and illustrate a new species, Macrostemum araca sp. nov., based on adult males and females from Serra do Aracá, Amazonas, Brazil, and the larvae and pupae of M. brasiliense (Fischer, 1970) from an Atlantic Forest fragment in São Paulo state using the metamorphotype method. In addition, this species is recorded for the first time for Minas Gerais state. © 2019, Museum National d'Histoire Naturelle. All rights reserved
Riverine people's knowledge of the Vulnerable Amazonian manatee Trichechus inunguis in contrasting protected areas
Get PDFTraditional knowledge gained through daily interactions with the environment can yield insights into processes at temporal or spatial scales that may be overlooked by conventional scientific research. Ninety interviews were conducted with riverine people in the vicinity of Anavilhanas National Park, Tapajós-Arapiuns Extractive Reserve and Tapajós National Forest in the Brazilian Amazon, with the aim to increase knowledge of the feeding habits of the Amazonian manatee Trichechus inunguis and evaluate its conservation status in contrasting protected areas. In Anavilhanas respondents identified 31 plant species consumed by the manatee, of which vines had the highest cognitive salience index value (the summed importance of each plant species), even though they are available to manatees only during the high-water season. In the Tapajós region 37 plant species were identified, with submerged species with floating leaves being the main component of the manatee's diet. Although hunting has declined it still occurs in Anavilhanas, which is susceptible to environmental crimes because of its proximity to urban centres. Manatee hunting seems to be infrequent in the Tapajós region, having little impact on the population. Given the broad knowledge within the local community about the Amazonian manatee, involvement of riverine people in manatee conservation activities is fundamental for reducing threats and increasing conservation effectiveness. Copyright © Fauna & Flora International 2019
Cross-reactivity between Potamotrygon motoro antivenoms and dorsal and stinger extracts of others stingrays (Chondrichthyes: Potamotrygonidae) from the Amazon basin
No full textIn this study, two mouse hyperimmune sera were produced, one using extract from the stinger of the stingray Potamotrygon motoro and the other using extract from the dorsal region of the same species and their cross-reactivity with extracts from the following species of stingrays from the Amazon basin was investigated using Western blot and dot ELISA: Paratrygon aiereba, Plesiotrygon iwamae, Potamotrygon orbignyi and Potamotrygon schroederi. The results show that the dorsal extract was as immunogenic as the stinger extract and induced high levels of antibodies, which reacted with homologous and heterologous antigens, indicating that both types of extract may be suitable for use in the production of antivenom to treat victims of envenomation by stingrays. © 2017, © 2017 Informa UK Limited, trading as Taylor & Francis Group
Phylogeography of the endangered sand dune whiptail lizard Glaucomastix abaetensis (Dias, Rocha & Vrcibradic, 2002) with the description of a new species
No full textSeveral species of Glaucomastix lizards have been described over the past decade, most of these inhabit inland Brazil. Glaucomastix abaetensis is a threatened whiptail endemic to Brazilian coastal “restinga” (sandy habitats) from Bahia State to Sergipe, with a distribution limited by riverine barriers. In order to investigate the differentiation and relationships in G. abaetensis, we integrated phylogeographic analysis, Bayesian species delimitation and morphological data to detect geographical patterns and historical events responsible for its present distribution. We recovered two highly divergent clades along its range, one of them unnamed. Glaucomastix itabaianensis sp. nov. has a a yellowish green tail, 13-16 scales in the lateral flank, 22-33 scales around tail, 28-35 femoral pores and usually four supraocular scales with the smaller one disposed posteriorly. Our results retrieved the monophyly of Glaucomastix, with G. venetacauda and G. cyanurus being sister species to a clade formed by G. littoralis and G. abaetensis. Divergence between Glaucomastix abaetensis and the new species occurred roughly 2.39 Myr ago; posterior shallow genetic divergences occurred mainly in Pleistocene. Finally, we present data on the conservation of this clade of whiptail lizards. Copyright © 2019 Magnolia Pres
Is the Phasmatodea male genitalia useful for systematics? A case study in Creoxylus and Prexaspes (Insecta: Phasmatodea) from the Brazilian Amazon Basin
No full textThe male genitalia have been neglected in Phasmatodea studies over the years. There are few works describing and illustrating this organ and no studies demonstrating its usage. Concerned by this matter, this paper aimed to investigate whether the male genitalia of Phasmatodea is useful for systematics. First, by describing a new species of Creoxylus Audinet-Serville (Creoxylus duckei sp. nov.) and including the description of its male genitalia, along with the differentiation from the male genitalia of the know species Creoxylus spinosus (Fabricius). By comparing these two genitalia, the first case of chirality in Phasmatodea was reported. Secondly, by describing the genitalia of two Prexaspes Stål species (Prexaspes viridipes Stål and another identified to genus level) and making the differentiation between them. Finally, by comparing all four described genitalia. Results showed that the male genitalia are useful to differentiation and identification of species/genera. It is discussed what knowledge can be drawn from these genitalia descriptions in terms of phylogeny of Xerosomatinae and Phasmatodea as a whole, as well as homologies with previous literature. © 201
Variação espacial das concentrações de metais-traço no solo e liteira de uma área de floresta natural
Get PDFTo consider that a certain soil is free of contamination, it is necessary to know the metal contents in this soil in natural conditions, without anthropic introduction, as well as in the vegetation, due to the importance of the biogeochemical cycle in the Amazon. Therefore, the determination of natural levels of metals in soil and litter is essential for the construction of a parameter that serves as a basis for the monitoring and remediation of contaminated areas and that is adequate to the local pedological and floristic reality. In this context, the objective of this research was to determine the natural calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), aluminum (Al), boron (B), barium (Ba), cobalt Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), silicon (Si), strontium (Sr), titanium V), zinc (Zn) and cadmium (Cd), as a reference base of quality for soils and for litter in a forest in central Amazonia, in the State of Amazonas. According to the results, the concentrations of the exchangeable or assimilable chemical elements in the soil followed the order: Al> Ca> Mg> K> Na, in which, in general, the majority was found in greater concentration in the Plateau / Slope. For the metallic elements a PCA was obtained, in which the main components 1 and 2, explained 89.12% and 10.87%, respectively, of the total variability of the data. The loadings of the main component 1 correlated positively with the majority of the metals, except for B, Cr, Mo, Ni, and these were positively correlated in the main component 2 (lower representativity). The mean macronutrient contents in the litter in decreasing order for plateau and valley area were Ca> K> Mg> Na. For the micronutrients, the order was from Al> Mn> Fe> Sr> Zn> Cu> Ba> Cr> Ni> Co> Cd for Plateau and Al> Mn> Fe> Sr> Zn> Cu> Ba> Cr> Ni > Cd> Co for the valley. Among the fractions, Ca had its highest concentration in the woody material; the K in the reproductive material, while the Mg, Na and Al had higher concentrations in the leaf fraction. The other elements were in very low concentrations in all compartments of the litter. It was also observed that the return to the soil of the metallic elements via litter, were higher in the dry season. Ca and Al differed significantly within the same area. Al and Zn differed significantly among the studied areas, with higher returns for both elements in the plateau area.Para considerar que um determinado solo está livre de contaminação, faz-se necessário conhecer os teores de metal neste solo em condições natural, sem introdução antrópica, assim como na vegetação, devido à importância do ciclo biogeoquímico na Amazônia. Portanto, a determinação de teores naturais de metais em solo e na liteira é essencial para a construção de um parâmetro que sirva de base ao monitoramento e remediação de áreas contaminadas e que seja adequada à realidade pedológica e florística local. Neste contexto, o objetivo desta pesquisa foi determinar os teores naturais de cálcio (Ca), magnésio (Mg), potássio (K), sódio (Na), alumínio (Al), boro (B), bário (Ba), cobalto (Co), cromo (Cr), cobre (Cu), ferro (Fe), manganês (Mn), molibdênio (Mo), níquel (Ni), silício (Si), estrôncio (Sr), titânio (Ti), vanádio (V), zinco (Zn) e cádmio (Cd), como base de referência de qualidade para solos e para liteira em uma floresta na Amazônia central, no Estado do Amazonas. De acordo com os resultados, as concentrações dos elementos químicos trocáveis ou assimiláveis no solo seguiram a seguinte ordem: Al > Ca > Mg > K > Na, no qual de forma geral, a maioria encontrou-se em maior concentração na área de Platô/Vertente. Para os elementos metálicos obteve-se uma ACP, na qual os componentes principais 1 e 2, explicaram 89,12% e 10,87% respectivamente da variabilidade total dos dados. Os loadings do componente principal 1 correlacionaram-se positivamente com a maioria dos metais, exceto para B, Cr, Mo, Ni, sendo estes correlacionados positivamente no componente principal 2 (mais baixa representatividade). A média dos teores de macronutrientes na liteira em ordem decrescente para área de platô e baixio foram Ca > K > Mg > Na. Para os micronutrientes, a ordem foi de Al > Mn > Fe > Sr > Zn > Cu > Ba > Cr > Ni > Co > Cd para o Platô e Al > Mn > Fe > Sr > Zn > Cu > Ba > Cr > Ni > Cd > Co para o baixio. Dentre as frações, o Ca teve sua maior concentração no material lenhoso; o K no material reprodutivo, enquanto o Mg, Na e Al, tiveram maiores concentrações na fração foliar. Os demais elementos estiveram em baixíssimas concentrações em todos os compartimentos da liteira. Observou-se também que o retorno para o solo dos elementos metálicos via liteira, foi maior na estação seca. O Ca e Al diferiram significativamente dentro de uma mesma área. Al e Zn diferiram significativamente entre as áreas estudadas, com maior retorno para ambos os elementos na área de platô
