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Rhinocricus Karsch, 1881 possui atualmente 207 espécies descritas e distribuídas principalmente pelo continente americano, das quais 65 são descritas para o Brasil. A descrição do gênero foi baseada na presença de escobinas (depressões na porção distal dos prozonitos). O presente estudo avaliou a monofilia de três grupos de espécies previamente propostos em Rhinocricus. A matriz de dados foi composta por 39 caracteres morfológicos e 30 espécies terminais, sendo 21 como grupo interno e nove do grupo externo. Nós realizamos uma analise de parcimônia com pesos implicitos usando o software TNT e obtivemos a melhor árvore com a mesma topologia para três melhores valores de K (5.992, 7.309, 9.105). Nenhum dos três grupos de espécies de Rhinocricus foi recuperado monofilético. Rhinocricus (Erythocricus) sanguineostriatus foi recuperado irmão de todas as outras espécies, e Argentocricus Verhoeff, 1941 resultou parafilético. Os caracteres diagnósticos tradicionalmente utilizados para separar grupos de espécies, subgênero e gênero não foram recuperados como sinapomorfias. Ainda durante o exame do material quatro novas espécies de Rhinocricus foram descobertas e são aqui descritas. Futuras investigações incluindo amostras mais amplas de espécies são necessárias, para estabelecer hipóteses de relacionamento robustas entre R. (Erythocricus), Argentocricus, e o restante das espécies de Rhinocricus, deste modo identificando grupos monofiléticos no gênero e suas sinapomorfias. / Rhinocricus Karsch, 1881 currently has 207 species described and distributed mainly by the American continent, of which 65 are described for Brazil. The genus was based on the presence of scobinae (depressions in distal portion of prozonit). The present study evaluated the monophyly of three groups of species previously proposed in Rhinocricus. The data matrix was composed for 39 morphological characters and 30 species as terminal taxa, being 21 the ingroup, and nine the outgroup. We performed a parsimony analysis with implied weights using TNT software, obtaining the same best topology with three optimal K-values (5.992, 7.309, 9.105). None of the three previously proposed species groups of Rhinocricus was recovered monophyletic. Rhinocricus (Erythocricus) was recovered sister to all other species, and Argentocricus Verhoeff, 1941 resulted paraphyletic. The diagnostic characters traditionally used to separate species groups, subgenera, and genera were not recovered as synapomorphies. Still during the examination of the material four new species of Rhinocricus were discovered and here described. Further investigation including a broader species sample is needed attempting to establish robust relationship hypotheses between R. (Erythocricus), Argentocricus, and the remainder species of Rhinocricus, thus identifying the monophyletic groups in the genus and their synapomorphies.

Rhinocricus Karsch, 1881 possui atualmente 207 espécies descritas e distribuídas principalmente pelo continente americano, das quais 65 são descritas para o Brasil. A descrição do gênero foi baseada na presença de escobinas (depressões na porção distal dos prozonitos). O presente estudo avaliou a monofilia de três grupos de espécies previamente propostos em Rhinocricus. A matriz de dados foi composta por 39 caracteres morfológicos e 30 espécies terminais, sendo 21 como grupo interno e nove do grupo externo. Nós realizamos uma analise de parcimônia com pesos implicitos usando o software TNT e obtivemos a melhor árvore com a mesma topologia para três melhores valores de K (5.992, 7.309, 9.105). Nenhum dos três grupos de espécies de Rhinocricus foi recuperado monofilético. Rhinocricus (Erythocricus) sanguineostriatus foi recuperado irmão de todas as outras espécies, e Argentocricus Verhoeff, 1941 resultou parafilético. Os caracteres diagnósticos tradicionalmente utilizados para separar grupos de espécies, subgênero e gênero não foram recuperados como sinapomorfias. Ainda durante o exame do material quatro novas espécies de Rhinocricus foram descobertas e são aqui descritas. Futuras investigações incluindo amostras mais amplas de espécies são necessárias, para estabelecer hipóteses de relacionamento robustas entre R. (Erythocricus), Argentocricus, e o restante das espécies de Rhinocricus, deste modo identificando grupos monofiléticos no gênero e suas sinapomorfias. / Rhinocricus Karsch, 1881 currently has 207 species described and distributed mainly by the American continent, of which 65 are described for Brazil. The genus was based on the presence of scobinae (depressions in distal portion of prozonit). The present study evaluated the monophyly of three groups of species previously proposed in Rhinocricus. The data matrix was composed for 39 morphological characters and 30 species as terminal taxa, being 21 the ingroup, and nine the outgroup. We performed a parsimony analysis with implied weights using TNT software, obtaining the same best topology with three optimal K-values (5.992, 7.309, 9.105). None of the three previously proposed species groups of Rhinocricus was recovered monophyletic. Rhinocricus (Erythocricus) was recovered sister to all other species, and Argentocricus Verhoeff, 1941 resulted paraphyletic. The diagnostic characters traditionally used to separate species groups, subgenera, and genera were not recovered as synapomorphies. Still during the examination of the material four new species of Rhinocricus were discovered and here described. Further investigation including a broader species sample is needed attempting to establish robust relationship hypotheses between R. (Erythocricus), Argentocricus, and the remainder species of Rhinocricus, thus identifying the monophyletic groups in the genus and their synapomorphies.

Rhinocricus Karsch, 1881 possui atualmente 207 espécies descritas e distribuídas principalmente pelo continente americano, das quais 65 são descritas para o Brasil. A descrição do gênero foi baseada na presença de escobinas (depressões na porção distal dos prozonitos). O presente estudo avaliou a monofilia de três grupos de espécies previamente propostos em Rhinocricus. A matriz de dados foi composta por 39 caracteres morfológicos e 30 espécies terminais, sendo 21 como grupo interno e nove do grupo externo. Nós realizamos uma analise de parcimônia com pesos implicitos usando o software TNT e obtivemos a melhor árvore com a mesma topologia para três melhores valores de K (5.992, 7.309, 9.105). Nenhum dos três grupos de espécies de Rhinocricus foi recuperado monofilético. Rhinocricus (Erythocricus) sanguineostriatus foi recuperado irmão de todas as outras espécies, e Argentocricus Verhoeff, 1941 resultou parafilético. Os caracteres diagnósticos tradicionalmente utilizados para separar grupos de espécies, subgênero e gênero não foram recuperados como sinapomorfias. Ainda durante o exame do material quatro novas espécies de Rhinocricus foram descobertas e são aqui descritas. Futuras investigações incluindo amostras mais amplas de espécies são necessárias, para estabelecer hipóteses de relacionamento robustas entre R. (Erythocricus), Argentocricus, e o restante das espécies de Rhinocricus, deste modo identificando grupos monofiléticos no gênero e suas sinapomorfias. / Rhinocricus Karsch, 1881 currently has 207 species described and distributed mainly by the American continent, of which 65 are described for Brazil. The genus was based on the presence of scobinae (depressions in distal portion of prozonit). The present study evaluated the monophyly of three groups of species previously proposed in Rhinocricus. The data matrix was composed for 39 morphological characters and 30 species as terminal taxa, being 21 the ingroup, and nine the outgroup. We performed a parsimony analysis with implied weights using TNT software, obtaining the same best topology with three optimal K-values (5.992, 7.309, 9.105). None of the three previously proposed species groups of Rhinocricus was recovered monophyletic. Rhinocricus (Erythocricus) was recovered sister to all other species, and Argentocricus Verhoeff, 1941 resulted paraphyletic. The diagnostic characters traditionally used to separate species groups, subgenera, and genera were not recovered as synapomorphies. Still during the examination of the material four new species of Rhinocricus were discovered and here described. Further investigation including a broader species sample is needed attempting to establish robust relationship hypotheses between R. (Erythocricus), Argentocricus, and the remainder species of Rhinocricus, thus identifying the monophyletic groups in the genus and their synapomorphies.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-04T13:47:47Z No. of bitstreams: 1 laravaztassi.pdf: 2483993 bytes, checksum: 0cfa5042c9ba9f1916e94ccc6e97c255 (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2016-10-04T13:50:51Z (GMT) No. of bitstreams: 1 laravaztassi.pdf: 2483993 bytes, checksum: 0cfa5042c9ba9f1916e94ccc6e97c255 (MD5) / Made available in DSpace on 2016-10-04T13:50:51Z (GMT). No. of bitstreams: 1 laravaztassi.pdf: 2483993 bytes, checksum: 0cfa5042c9ba9f1916e94ccc6e97c255 (MD5) Previous issue date: 2010-02-25 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os artrópodos constituem um grupo que possui um extenso registro fossilífero e hoje constitui o grupo mais abundante e diverso dos animais terrestres. Suas pistas fossilizadas, aliadas a estudos geológicos, fornecem dados importantes para estudos paleoecológicos. Através da análise da oscilação da densidade de icnofósseis ao longo dos horizontes do Parque do Varvito (Município de Itu – SP) foram realizadas inferências sobre a história geológica da área, sobre a população de artrópodos que provavelmente ali viveu e sobre as condições ambientais que a circundava. Para isso foram utilizadas metodologias como a do esquadrinhamento para obter informações a respeito da densidade e direcionamento das pistas e experimentos com a finalidade de reproduzir as pistas em condições semelhantes aquelas encontrados no parque. Além disso, foi realizada uma classificação icnotaxonômica das pistas e sua atribuição a diplópodos (Myriapoda) terrestres. A contextualização da análise tafonômica com a história deposicional do Parque do Varvito levou a conclusão de que os miriápodos, de hábitos terrestres, habitavam uma área de inundações cíclicas e, conseqüentemente, passavam por condições de estresse ambiental no verão, quando a área recebia o afluxo da água de degelo de uma geleira localizada a uma distância relativamente grande da região do Parque durante o Carbonífero. A condição de estresse ambiental para esta fauna, que poderia ou não causar episódios de mortalidade, ocorria em função de uma fina lâmina d’água que provinha da geleira. Pelo fato das pistas estarem com direcionamento preferencial, pode-se inferir que esses animais fugiam das inundações durante o verão (condição estressante), cujo fluxo de água teria provavelmente uma orientação similar. Considerando as evidências da influência periglacial e o aporte da água de degelo, o frio intenso poderia ter levado ao congelamento dos solos no ambiente terrestre, gerando ambientes subaquáticos rasos, bem como a formação de capas de gelo, o que dificultaria as trocas gasosas e a obtenção de nutrientes. As pistas também apresentam formas circulares e semicirculares que foram interpretadas como marcas de agonia do animal sob situação de estresse, corroborando a reconstrução paleoecológica inferida no presente estudo. / The arthropods represent the most extensive fossil register and the most abundant and diverse group of all terrestrial animals. Their track and trails provide important data for the study of this group evolution besides helping understanding their diversity and modern distribution. By analyzing the oscillation of the density of ichnofossils along the horizons of Varvito´s Park (Itu – SP), were made inferences about the geological history of the area, the population of arthropods that probably lived there and on the environmental conditions that surrounded them. For the analysis of the density and direction of the tracks, the methodology used was the esquadrinhamento. Also, an experiment was conducted in order to replicate the tracks in similar conditions to those found in the Park during the Carboniferous. It was made a taxonomic classification of the tracks and they were assigned to terrestrial diplopods (Myriapoda). The contextualization of the taphonomic analysis and the depositional history of Varvito´s Park led to the conclusion that myriapods, which have terrestrial habits, inhabited an area of cyclic flooding and therefore experienced environmental stress conditions in the summer, when the area received an influx of meltwater from a glacier located at a relatively long distance of the Park during the Carboniferous. The condition of environmental stress for this fauna, which may or may not cause episodes of mortality, was taking place due to the a thin sheet of water that came from the glacier. Because the tracks were in a preferred direction, one can infer that these animals got away from floods during the summer (stressful condition), which flow of water would probably have a reverse orientation. Considering the evidences of periglacial influence and the outflow of meltwater, the cold might have led to the freezing of soils in the terrestrial environment, creating shallow underwater environments, as well as the formation of ice sheets, thereby impeding gas exchange and the obtainment of nutrients. The tracks also present circular and semi-circular forms and have been interpreted as marks of animals’ agony under stressed conditions, corroborating the paleoecological reconstruction inferred.

Scotland is one of the most valuable regions available for geologic study, as it has been a breeding ground for the discovery and development of many fundamental concepts from the earliest studies in the field through today. Scotland has traditionally been viewed, in a broad sense, as the amalgamation of two components: the eroded remnants of the Caledonide Orogen north of the Highland Boundary Fault (HBF), and the post-Caledonian Old Red Sandstone (ORS) to the south. Studies based in the Scottish Caledonides and the ORS have provided a host of concepts that we now deem fundamental, but much of that has been the byproduct of effort to understand how they were juxtaposed along the HBF. The metamorphosed strata of the Grampian Terrane (GT) lie against pillow basalts and minor sediments associated with the Highland Border Complex (HBC), and undeformed fluvial deposits of the ORS near the Highland Border. The incompatibility of lithologies, but also palaeontologic and radiometric ages, on either side of the fault was seemingly inexplicable, and coined the term “the Highland Border Paradox”. The Highland Border Paradox was used to describe the conflicting idea of continuity between the GT and HBC, despite incompatible lithologies and ages within the section. Several tectonic models have been suggested as a solution to the core of the issue, but a widely accepted solution has so far been elusive. The 40Ar/39Ar method is well-poised to investigate when the Scottish Caledonides were active, and when the ORS was deposited; each valuable in their own dimension but combined represent the best opportunity to understand the Highland Border Paradox to date. Two models exist: one which considers the Midland Valley Terrane (MVT; predominately ORS) to be relatively autochthonous relative to the northern terranes, and another that suggests the MVT is mostly allochthonous, or exotic. This dissertation is designed as a multi-pronged approach to offer an overarching understanding of the relationship between the Scottish Caledonides and the ORS, but with the intention that each chapter is a standalone contribution. We first investigate the relationship between the Grampian Terrane and the Old Red Sandstone by studying the contact that bounds them, which is along the Highland Boundary Fault. The base of the ORS is only reported to be exposed at five localities along the northern margin of the Midland Valley, but the basal unconformity is only found at Stonehaven. Outcrop exposure is not ideal in Scotland, such that the exposure of the contact between the GT and MVT is only exposed at those few localities, and physically tracing contacts between those localities is not possible. Chapter 1 is focused on exposure of the contact from the locality near Stonehaven, where we were surprised to find that no unconformity exists, and that the base of the ORS is a fault. A new age 40Ar/39Ar age of 438 Ma from biotite separated from a dike that crosscuts the Cowie Formation is over 20 Myr older than previous estimates, pushing the base of the ORS well into the Silurian. Fossils of Pneumodesmus Newmani found there, the earliest documented terrestrial and air-breathing fauna in the geologic record, must also be as old as 438 Ma. This pushes back both the timing of when air-breathing animals emerged from land, but also reinstates Stonehaven as the ideal locality to study the earliest life on land. This chapter was designed to be a manuscript for submission to Geology, or a similar journal, as it is a famous locality pertinent to a host of Caledonian studies, is commonly used for teaching, and has broad interest to the scientific community with respect to Pneumodesmus Newmani. Chapter 2 is focused on studying the physical contact between the GT and MVT at its other reported localities: Edzell (North Esk River), Callander, and Balmaha. Detailed field mapping and observations were made for each, also supplemented petrographic details from thin sections as needed. One of the most surprising findings is that, combined with observations from Stonehaven, the base of the ORS is either faulted or not exposed; there is effectively no evidence for a basal ORS unconformity. This releases the constraints that the ORS was deposited strictly after the Caledonian Orogeny, and that the ORS was deposited above the GT/HBC stack as we see it today. In addition, at each of these localities, we identify considerable evidence of faulting in the area between the GT and MVT; most affected is the intervening HBC. This is hard to reconcile with previous interpretations proposed for those localities by proponents of the autochthonous model, as it is based largely on proposed continuity at those localities. It is also difficult to reconcile with the suggestion, in that view, that the HBF only modestly displaces geology, and not responsible for the juxtaposition of the GT and MVT. Evidence at each locality for undeformed units directly juxtaposed with highly deformed rocks implies a significant amount of vertical displacement that has not previously been appreciated, in any previous account. A significant amount of vertical displacement is a characteristic of major strike-slip faults, yet previous strike-slip models for the HBF have invoked movements in a purely lateral sense. Chapter 3 aims to constraint when the GT, Northern Highland Terrane (NHT), and Hebridean Terrane (HT) were exhumed during the Caledonian Orogeny, with a particular focus on the southern region of the GT near the HBF. We employed single-step 40Ar/39Ar analysis of muscovite separated from bedrock exposed throughout the terranes north of the HBF, complementing a similar work by Dewey and Pankhurst (1970). Throughout all the terranes, these ages range from 500-420 Ma, with a concentration of ages ca. 470 Ma. Combined with previous data sets, the NHT appears to have had a younger exhumation, but if our dataset is considered alone that distinction is unclear. The second portion of Chapter 3 presents the results of step-heating 40Ar/39Ar analysis of muscovite separated from metamorphosed GT strata, sampled in transects spanning across the metamorphic zones of the GT. The purpose of the transects is to evaluate when the portion of the GT immediately against the MVT was active. The step-heating analyses range between 471-461 Ma at Stonehaven, 468-453 Ma at North Esk, and 459-447 Ma at Balmaha (combined with Callander). These ages indicate that the Caledonian Orogeny was active at least from ca. 471-447 Ma, whereas the Caledonian Orogeny was previously proposed to be unusually short (10 Myr). As these ages likely capture the latest stage of orogenesis, the actual duration is likely considerably longer, and this is also suggested by the wider range of single-step ages. It is also now difficult to envision a scenario in which the GT was a passive margin through Ordovician times, which is a widely accepted notion. Chapter 4 is designed to investigate the time at which the Midland Valley ORS was deposited, and where its sediments originated from. We obtained three ages from volcanic units interleaved throughout the ORS, including a result of 438 Ma near the base (from Stonehaven), a result of 431 Ma from the Lintrathen Porphyry near mid-section, and a result of 400 Ma at the top of the ORS near Oban. We sampled over ten volcanic units interleaved within the ORS, but most ultimately were unsuitable for age analysis. Despite only obtaining three ages, it is now clear that at least the onset of ORS sedimentation is significantly older than previous estimates, now as far back as 438 Ma, whereas it was previously considered to be mostly Devonian. Considering that the age from Lintrathen at midsection is only 6 Myr younger, and still Silurian, it is possible that a majority of the Midland Valley LORS is Silurian, and deposited within a much more narrow timeframe than previously suggested. The result of 399 Ma from Oban confirms the previous suspicion that the ORS near Oban is unrelated to the ORS in the Midland Valley. Detrital analyses from the Midland Valley ORS indicate a source that ranges in age from mainly 480-420 Ma, which effectively overlaps the Scottish source ages obtained in Chapter 3. This is at odds with a previous hypothesis that suggested the ORS was sourced from large river systems from Scandinavia (including the Western Gneiss Region), analogous to the Himalayan drainages today. In combination, the depositional ages (437 and 431 Ma) and range of detrital ages (480-420 Ma), suggest that the ORS was locally related to the Scottish Caledonides, rather than an exotic origin. So, while it is now clear that displacement along the HBF is more substantial than previously conceived, that displacement was not significant enough to isolate the ORS from a Scottish source.