Uma revisão taxonômica gênero Leporacanthicus Isbrücker & Nijssen, 1989 é apresentada, bem como uma hipótese filogenética de relacionamento das espécies, e de seu posicionamento dentro da tribo Ancistrini. Quatro espécies distribuídas no planalto Brasileiro e das Guianas, bacias Amazônica e do Orinoco são consideradas válidas: L.galaxias (rios Tocantins, Guamá e Orinoco); L. joselimai (rios Tapajós e Curuá-Una); L. heterodon (rio Xingu); e L. triactis (rio Orinoco). A análise resultou em dois cladogramas igualmente parcimoniosos com 336 passos (IC=0,43; IR=0,66), do qual foi gerado uma árvore de consenso estrito. O monofiletismo de Leporacanthicus é corroborado por 14 sinapomorfias; dentro do gênero foi obtida a seguinte topologia (L. galaxias (L. triactis (L. heterodon, L. joselimai))). Os resultados apresentados aqui sugerem que Pseudacanthicus representam o grupo irmão de Leporacanthicus, diferindo de propostas anteriores obtidas com caracteres morfológicos e/ou moleculares. / A taxonomic review of the genus Leporacanthicus Isbrücker & Nijssen, 1989 is presented, as well as a phylogenetic hypothesis of species relationships, and it position within the tribe Ancistrini. Four species distributed in the Brazilian and Guiana Shields, Amazon and Orinoco Basins, are recognized as valid: L.galaxias (rios Tocantins, Guam and Orinoco); L. joselimai (rios Tapajós and Curuá-Una), L. heterodon (rio Xingu); e L. triactis (rio Orinoco). The phylogenetic analysis resulted in two cladogramas equally parsimonious with 336 steps (CI=0,43; RI=0,66), from which a strict consensus tree was generated. The monophyletism of Leporacanthicus is corroborated by 14 synapomorphies; within the genus the following topology was obtained: (L. galaxias (L. triactis (L. heterodon, L. joselimai))). The results presented herein suggest that Pseudacanthicus is considered to be the sister-group of Leporacanthicus, differing from previous hypothesis obtained using molecular and/or morphological dada.

O objetivo geral deste trabalho é investigar as possibilidades de integração entre o norte do Brasil e a Venezuela com base nos planos de desenvolvimento regional dos dois países, em suas políticas externas e nas iniciativas de integração da América do Sul. A hipótese central é a de que a formulação e a execução de um plano nesses moldes só são possíveis em um contexto em que as fronteiras sejam entendidas mais como oportunidade de integração e desenvolvimento conjunto do que como espaço de disputas e ameaças, em que o planejamento, as políticas públicas e a cooperação técnica extrapolem o âmbito nacional e tenham como objetivo maior a diminuição de assimetrias. Para tanto, apresenta-se o debate sobre a relação entre desenvolvimento e planejamento na construção teórica latino-americana e sua relação com o processo integracionista regional; em seguida, os planos de desenvolvimento dos dois países, enfatizando que historicamente foram pensados de forma exclusivamente nacional (interna), desconsiderando as potencialidades da integração com os vizinhos e de um projeto regional de desenvolvimento; pretende-se também discutir as mudanças no contexto regional que possibilitaram a articulação conjunta de políticas para o desenvolvimento regional, principalmente no período mais recente e avaliar as ações das instituições contemporâneas de desenvolvimento regional, notadamente a Sudam, Suframa, o Projeto Calha Norte e o Banco da Amazônia, no Brasil, e a CVG, o Mibam, o Projeto Socialista Orinoco (PSO) e o Plan Guayna Socialista, na Venezuela; por fim, discutem-se as especificidades das relações entre Brasil e Venezuela e a importância da nova cooperação entre os dois países para a diminuição das assimetrias, além do protagonismo de Brasil e Venezuela no processo de integração atual. / This thesis aims to investigate the possibilities of integration between the north of Brazil and Venezuela based on their regional development plans, their external politics and on the initiatives for integration of South America. The main hypothesis is that the formulation and execution of this kind of plan is only possible in a context where the borders are seen as opportunity for integration and joint development instead of seen as space of dispute and threat; in a context in which the planning, the public policies and the technical cooperation extrapolate the nations with the objective of decrease the asymmetries. Thus, the thesis starts with the discussion about the Latin-American theoretical debate of the relation between development and planning. After that, it discuss the Plans for development of both countries, emphasizing that historically these plans where planned to be exclusively internal (national), disregarding the prospective of integration with neighbors as well as the prospective of a regional development project. Then, the text discusses the regional context changes that made possible the joint articulation of policies for regional development, especially done today, and evaluate the contemporary institutional actions for regional development, markedly Sudam, Suframa, Projeto Calha Norte and Banco da Amazônia, in Brazil, and CVG, Mibam, Proyecto Socialista Orinoco (PSO) and Plan Guayna Socialista, in Venezuela. Finally, this thesis discuss the special relationship between Brazil and Venezuela and the importance of the new cooperation between them to decrease the asymmetries, besides their role on todays integration process.

O gênero Paratrygon Duméril (1865) até então reconhecido como único gênero monotípico da família Potamotrygonidae, apresenta uma diversidade consideravelmente alta e já apontada previamente por estudos moleculares que indicavam sua única espécie P. aiereba como um possível complexo de espécies. Oitos novos grupos específicos foram aqui reconhecidos através de dados morfológicos e morfométricos: P. sp.1 e P. sp.2 endêmicos e simpátricos da bacia do Orinoco, P. sp.3 endêmico do Rio Branco, P. sp.4 endêmico do Rio Negro, P. sp.5 endêmico do Rio Tapajós, P. sp.6, endêmico do Rio Araguaia, P. sp.7, endêmico do Rio Tocantins e P. sp.8 endêmico do Rio Xingu. Distribuição de P. aiereba está restrita para bacia Amazônica. Todos os grupos específicos foram identificados e definidos através de caracteres como coloração, morfologia dos dentículos dérmicos, espinhos pontiagudos da cauda, distribuição dos canais ventrais da linha lateral, morfologia dos elementos esqueléticos e morfometria. Espécie nominal Disceus thayeri Garman (1913) foi confirmada como sinônimo junior para P. aiereba através da análise de seus espécimes-tipo (MCZ 297-S, 563-S, 606-S). Espécie nominal Trygon strogylopterus Schomburgk (1843) foi correlacionada a um dos grupos específicos, P. sp.3, através de análise morfológica de seu espécime-tipo ZMB 4632 e portanto futuramente será revalidada. Por fim, os agrupamentos Paratrygon + Heliotrygon e Potamotrygon + Plesiotrygon são corroborados também através de caracteres morfológicos e dados morfométricos, e o reconhecimento taxonômico desses dois grandes grupos dentro da família Potamotrygonidae se vê necessário para melhor compreensão evolutiva dos potamotrigonídeos / The genus Paratrygon Duméril (1865) so far recognized as the unique monotypic genus of the family Potamotrygonidae, shows a considerable high diversity previously indicated by molecular studies which pointed P. aiereba (its unique species) as a possible species complex. Eight new specific groups were recognized here through morphological and morphometric data: P. sp.1 and P. sp.2 endemic and sympatric to Orinoco basin, P. sp.3 endemic to Rio Branco, P. sp.4 endemic to Rio Negro, P. sp.5 endemic to Rio Tapajós, P. sp.6, endemic to Rio Araguaia, P. sp.7, endemic to Rio Tocantins, and P. sp.8 endemic to Rio Xingu. Distribuiton of P. aiereba is restricted to Amazon basin. All specific groups were identified and defined through caracters such as coloration, dermal denticles morphology, pointed caudal spines, distribution of ventral canals of lateral line, morphology of skeletal elements and morphometrics. Nominal species Disceus thayeri Garman (1913) was confirmed as junior synonymous of P. aiereba by analyzes of its type-specimens (MCZ 297-S, 563-S, 606-S). Nominal species Trygon strogylopterus Schomburgk (1843) was correlated to one of the specific groups, P. sp.3, by morphological analyzes of its type-specimen ZMB 4632 and therefore will soon be resurrected. Lastly, the clades Paratrygon + Heliotrygon and Potamotrygon + Plesiotrygon are also corroborated by morphological and morphometric data, and the taxonomic recognition of these groups inside the family Potamotrygonidae it turns out necessary to better understanding the evolution of neotropical freshwater stingrays

O objetivo geral deste trabalho é investigar as possibilidades de integração entre o norte do Brasil e a Venezuela com base nos planos de desenvolvimento regional dos dois países, em suas políticas externas e nas iniciativas de integração da América do Sul. A hipótese central é a de que a formulação e a execução de um plano nesses moldes só são possíveis em um contexto em que as fronteiras sejam entendidas mais como oportunidade de integração e desenvolvimento conjunto do que como espaço de disputas e ameaças, em que o planejamento, as políticas públicas e a cooperação técnica extrapolem o âmbito nacional e tenham como objetivo maior a diminuição de assimetrias. Para tanto, apresenta-se o debate sobre a relação entre desenvolvimento e planejamento na construção teórica latino-americana e sua relação com o processo integracionista regional; em seguida, os planos de desenvolvimento dos dois países, enfatizando que historicamente foram pensados de forma exclusivamente nacional (interna), desconsiderando as potencialidades da integração com os vizinhos e de um projeto regional de desenvolvimento; pretende-se também discutir as mudanças no contexto regional que possibilitaram a articulação conjunta de políticas para o desenvolvimento regional, principalmente no período mais recente e avaliar as ações das instituições contemporâneas de desenvolvimento regional, notadamente a Sudam, Suframa, o Projeto Calha Norte e o Banco da Amazônia, no Brasil, e a CVG, o Mibam, o Projeto Socialista Orinoco (PSO) e o Plan Guayna Socialista, na Venezuela; por fim, discutem-se as especificidades das relações entre Brasil e Venezuela e a importância da nova cooperação entre os dois países para a diminuição das assimetrias, além do protagonismo de Brasil e Venezuela no processo de integração atual. / This thesis aims to investigate the possibilities of integration between the north of Brazil and Venezuela based on their regional development plans, their external politics and on the initiatives for integration of South America. The main hypothesis is that the formulation and execution of this kind of plan is only possible in a context where the borders are seen as opportunity for integration and joint development instead of seen as space of dispute and threat; in a context in which the planning, the public policies and the technical cooperation extrapolate the nations with the objective of decrease the asymmetries. Thus, the thesis starts with the discussion about the Latin-American theoretical debate of the relation between development and planning. After that, it discuss the Plans for development of both countries, emphasizing that historically these plans where planned to be exclusively internal (national), disregarding the prospective of integration with neighbors as well as the prospective of a regional development project. Then, the text discusses the regional context changes that made possible the joint articulation of policies for regional development, especially done today, and evaluate the contemporary institutional actions for regional development, markedly Sudam, Suframa, Projeto Calha Norte and Banco da Amazônia, in Brazil, and CVG, Mibam, Proyecto Socialista Orinoco (PSO) and Plan Guayna Socialista, in Venezuela. Finally, this thesis discuss the special relationship between Brazil and Venezuela and the importance of the new cooperation between them to decrease the asymmetries, besides their role on todays integration process.

Uma revisão taxonômica gênero Leporacanthicus Isbrücker & Nijssen, 1989 é apresentada, bem como uma hipótese filogenética de relacionamento das espécies, e de seu posicionamento dentro da tribo Ancistrini. Quatro espécies distribuídas no planalto Brasileiro e das Guianas, bacias Amazônica e do Orinoco são consideradas válidas: L.galaxias (rios Tocantins, Guamá e Orinoco); L. joselimai (rios Tapajós e Curuá-Una); L. heterodon (rio Xingu); e L. triactis (rio Orinoco). A análise resultou em dois cladogramas igualmente parcimoniosos com 336 passos (IC=0,43; IR=0,66), do qual foi gerado uma árvore de consenso estrito. O monofiletismo de Leporacanthicus é corroborado por 14 sinapomorfias; dentro do gênero foi obtida a seguinte topologia (L. galaxias (L. triactis (L. heterodon, L. joselimai))). Os resultados apresentados aqui sugerem que Pseudacanthicus representam o grupo irmão de Leporacanthicus, diferindo de propostas anteriores obtidas com caracteres morfológicos e/ou moleculares. / A taxonomic review of the genus Leporacanthicus Isbrücker & Nijssen, 1989 is presented, as well as a phylogenetic hypothesis of species relationships, and it position within the tribe Ancistrini. Four species distributed in the Brazilian and Guiana Shields, Amazon and Orinoco Basins, are recognized as valid: L.galaxias (rios Tocantins, Guam and Orinoco); L. joselimai (rios Tapajós and Curuá-Una), L. heterodon (rio Xingu); e L. triactis (rio Orinoco). The phylogenetic analysis resulted in two cladogramas equally parsimonious with 336 steps (CI=0,43; RI=0,66), from which a strict consensus tree was generated. The monophyletism of Leporacanthicus is corroborated by 14 synapomorphies; within the genus the following topology was obtained: (L. galaxias (L. triactis (L. heterodon, L. joselimai))). The results presented herein suggest that Pseudacanthicus is considered to be the sister-group of Leporacanthicus, differing from previous hypothesis obtained using molecular and/or morphological dada.

Cette thèse analyse le discours et les pratiques des Jésuites missionnaires au Casanare-Orénoque, territoire qui correspond actuellement aux régions des plaines orientales colombiennes et du cours bas et moyen de l’Orénoque (Colombie et Venezuela). Elle inscrit l’action jésuite dans ces territoires dans le contexte universel des missions catholiques en étudiant l’esprit de corps des missionnaires sous son aspect institutionnel et en tant que vocation ascétique. Elle présente aussi, à travers l’étude des vies missionnaires, des aspects historiques plus spécifiques du travail apostolique. Elle analyse également trois problématiques de l’action évangélique dans sa relation avec la colonisation : la conquête des Indiens, le degré d’autonomie ou de dépendance des villages-missions vis-à-vis du monde laïque, et le rôle politique et culturel de la mission comme marqueur d’une frontière territoriale. Elle étudie enfin les discours sur l’Indien et les pratiques pastorales. / The thesis analyses the discourses and practices of Jesuit missionaries in the former Casanare-Orénoque region, which roughly covers the plains in today’s eastern Colombia as well as the lower part of the Orinoco river. The study describes the missionary work of the Jesuits in its universal context of catholic missions and focuses on the corps spirit of the missionaries in its institutional aspect and its ascetic vocation. Thus, by concentrating on missionary live cycles, more specific historical aspects of apostolic work are investigated. Three sets of questions about evangelical action in its relation to colonization are also raised: the conquest of the Indians, the missionary village’s degree of autonomy or dependence in relation to the laic world, and the political and cultural role of the missions in the establishment of a territorial frontier. Finally, the discourses about the Indians and the pastoral practices are studied.

The study uses subsidence analysis of three deep wells to basement combined with sequence stratigraphic mapping to show that a 85,000 km² area of the Eastern Venezuelan foreland basin in the region of the Orinoco Delta underwent three main stages of foreland-related subsidence that followed a protracted Cretaceous - late Oligocene period of precollisional, passive margin formation. Phase 1 consists of increased foreland basin subsidence in the late Oligocene to middle Miocene (23 - 13 Ma) at average sedimentation rates of 0.14 mm/yr. Clastic rocks of Phase 1 include the Freites Formation, a 1.2 km-thick section of greenish-gray fissile shale and shaly sandstone deposited in shallow marine- neritic environments. Seismic facies show progradation of Phase 1 clastic rocks as a wedge from the NE and NNE. Clastic rocks deposited during the accelerated Phase 2 in the middle to late Miocene (13 -11 Ma at sedimentation rates of 1.45 mm/yr) include the La Pica Formation, a 2.7 km-thick section of gray silt and fine-grained sandstone deposited in shallow marine/coastal proximal environments. Seismic facies show progradation of Phase 2 clastic rocks as a wedge to the northeast. Phase 3 consists of decelerating foreland basin subsidence in the period of late Miocene-mid Pliocene (11-6 Ma at average sedimentation rates of 0.86 mm/yr). Sedimentary rocks deposited during this period include the Las Piedras Formation, a 1.45 km-thick section of sandstone, carbonaceous siltstone and shale deposited in deltaic environments. Seismic facies show a progradation of Phase 3 clastic rocks as a wedge to the northeast and east-northeast. Deeper marine environments and more rapid subsidence rates of Phases 1 and 2 are interpreted as an underfilled foreland basin controlled by active thrusting along the Serrania del Interior at the northern flank of the basin. Deltaic environments and slower rates of Phase 3 are interpreted as an overfilled foreland related to rapid seaward progradation of the Orinoco Delta and its filling of the former, dynamically- maintained interior seaway. Paleogeographic maps constrained by wells and seismic lines show a large regression of the Orinoco River towards the west across the Columbus basin and Eastern Venezuelan basin during the late Miocene and the Paleocene. In this foreland basin setting, the effects of thrust-related tectonic subsidence and early deposition of the Orinoco Delta play a larger role in the early Miocene-Pleistocene sequences than eustatic effects. / text

This dissertation addresses the intersection of rhetoric and material exchange in the construction of political alliance and conflict between the Waraos indigenous population and the non-indigenous institutions and political actors in the Orinoco Delta, Venezuela. It deals with the discursive and material strategies used to construct political reality at the moment of the emergence of one of the so-called new South American left wing populist governments (Hugo Chavez presidency since 1998). These historical circumstances present an opportunity to open a discussion bringing together the recent developments of discourse-centered approaches to culture, language ideologies, and the most classical theories on material exchange. This research's aim is to understand how multiple sign systems (in this case language and material gifts) interact, contradict, and support each other. In sum, this dissertation uses the advances of discourse-centered approaches to culture and the anthropological theories of exchange to understand how language and gift giving has shaped history and political imagination in the Orinoco Delta and Venezuela.

The study area is situated along the obliquely converging boundary of the Caribbean and South American plates offshore eastern offshore Trinidad. Major structural elements in the shelf break and deep-water slope regions include normal and counter-normal faults to the south and large transpressional fault zones to the north. Well logs and biostratigraphic information were analyzed for twenty-four wells in the study area to refine previous depositional environment interpretations. For purposes of this net sand distribution analysis it was decided to consider the deltaic portion of the shelf transit cycle, against the marine portion of the shelf transit cycle and were named T and R cycles, respectively. T and R cycles were interpreted based on well log patterns and depositional facies shifts. Six T/R cycles were interpreted within the Pliocene to recent stratigraphic succession and shelf edge trajectories were also mapped for each of these cycles based on earlier stratigraphic correlations. Net-to-gross (NTG) ratios were calculated for each component of the T/R cycles and plotted against total thicknesses and net sand values. In addition, NTG trends were mapped for each interval and analyzed based on their proximity to the corresponding shelf edge. Mapping of the shelf edge trajectories (SET) revealed that (1) SET migrate northeasterly across the Columbus Basin through time and (2) shelf edge orientations are parallel to the strike of growth faults in the south but deflect to the northeast near the Darien Ridge indicating a strong underlying structural control. The NTG plots and maps also revealed that (1) For T cycles, NTG values never exceed 60% and are inversely proportional to total thickness, (2) For R cycles, NTG values are highly variably ranging from 35% to 90%, (3) NTG values increase as the shelf break is approached and (4) The distribution of NTG ratios is also controlled by accommodation space created by local structures. The Guiana current is believed to play an important role in the redistribution and reworking of sand in the Columbus Basin. Aggradation and progradation distances were computed for each interval and the results suggest that the younger Sequences C2 (T-R cycle E) and C3 (T-R cycle F) show a stronger progradational trend than the older C4, C5 and C6. This strong progradational trend might indicate delivery of sand basinwards, while for the older intervals; the aggradational trend suggests an increase in sediment storage. In long-term scale (1-2 m.y.) the Orinoco Delta seems to behave as an aggradational delta that increases sediment storage due to growth fault and high subsidence rates. However, in the short-term scale, the Orinoco delta seems to behave as a rapid progradational delta, for the younger sequences C2 and C3, where sediment bypass is more likely to occur; and as a rapid aggradational (slow prograding) margin for the older intervals C4, C5 and C6. / text

Freshwater ecosystem degradation in the Amazon and Orinoco river basins is increasing due to rising human population numbers, and large water development projects. Therefore, monitoring ecosystem condition in these rivers of high biodiversity is of global conservation importance. This dissertation evaluated the potential of using river dolphins as indicators of ecosystem condition in large tropical rivers of South America. First, population estimates of river dolphins were obtained by line-strip transect surveys and mark-recapture methods on photo-identifications. Using this information, I identified critical habitat, hotspots, and areas of concern for river dolphins, as well as the relationship between dolphin density and group size estimates with ecological features. Second, I evaluated the relationship between dolphin estimates and human stressors. Higher densities of dolphins occurred in rivers with low indices of overall freshwater degradation, such as rivers with high water quality and the lowest human population numbers. Thus, dolphin density estimates seem to be good indicators of freshwater ecosystem degradation in the Amazon and Orinoco basins. These top predators not only are indicator species, but also have the potential to act as flagship and sentinel species, indicating freshwater ecosystem degradation and stimulating conservation action. This dissertation highlights the large changes in the Amazon and Orinoco that are approaching fast. Indicator, flagship and sentinel species can become science-based conservation tools not to only document freshwater ecosystem degradation, but to raise awareness about broader implications of human stressors on biodiversity and river systems.