UnB/IG - DISSERTAÇÕES E TESES DE OUTROS CURSOS
DE PÓS-GRADUAÇÃO NO BRASIL

cpggeo/Curso de Pós-Graduação em Geociências - UFRGS
DISSERTATIONS (Ms.C)- PALEONTOLOGY- (this page)
Dissertações de Mestrado PALEONTOLOGIA -(esta página)

[MSc Theses(Stratigraphy) ]
[MSc Theses(Marine Geology) ]
[MSc Theses(Geochemistry) ]
[PhD Theses ]

DISTRIBUIÇÃO BATIMÉTRICA DE FORAMINÍFEROS RECENTES AO LONGO DA PLATAFORMA CONTINENTAL SULBRASILEIRA (RIO GRANDE DO SUL, BRASIL)

BATHYMETRIC DISTRIBUTION OF RECENT FORAMINIFERA ALONG THE SOUTHERN BRAZILIAN CONTINENTAL SHELF (RIO GRANDE DO SUL, BRAZIL)

Érica Ulrica Röettger (1970)

Adviser: Darcy Closs

Abstract

Recent foraminifera collected in the Continental Shelf of Rio Grande do Sul State, between latitudes 29°S and 33°S, were studied in order to: a) determine the bathymetric associations at successive depths; b) recognize the species biologically indicative of the Brazil and Falklands Currents; c) elaborate a qualitative and quantitative account on the species found and compare with those pertaining to ecologically equivalent areas.

The following bathymetric associations were found:

_ Between 13 and 83m: Elphidium discoidale, Elphidium aff. discoidale, Nonionella atlantica and Nonion grateloupi grateloupi;

_ Between 22 and 95m: Buliminella elegantissima;

_ Between 34 and 135m: Cassidulina crassa forma minima, Bulimina marginata forma typica and Bolivina fragilis;

_ Between 46 and 143m: Uvigerina peregrina forma parvula.

The survey revealed 189 benthic and 22 planktonic species. Among the biologically indicative species, those associated with the Brazil Current predominate. Benthic species associated with the Falklands Current have a low percentage of occurrence (27%), whereas the planktonic ones, though qualitatively numerous, occur as isolated specimens.

REVISÃO DO GÊNERO CYTHERIDELLA (OSTRACODA)

ECOLOGIA, DISTRIBUIÇÃO ESTRATIGRÁFICA, PALEOGEOGRAFIA

REVISION OF THE GENUS CYTHERIDELLA (OSTRACODA)

ECOLOGY, STRATIGRAPHIC, DISTRIBUTION, PALEOGEOGRAPHY

Ivone Purper (1970)

Adviser: Irajá Damiani Pinto

Abstract

For a better interpretation of the systematics, ecological, palaeoecological and stratigraphic studies of the genus Cytheridella Daday 1905, a complete revision was made, as well as a redescription of the type­species, based on the type material of Daday.

Other species of the genus, including a new one - Cytheridella boldii n.sp. - were also studied. The results of this research led to new ecological, palaeoecological and palaeogeographic interpretations and to the identification of the stratigraphic distribution of the genus from the Eocene to the Recent.

DISTRIBUIÇÃO ECOLÓGICA DAS TECAMOEBAS E FORAMINÍFEROS EM AMBIENTES MIXOHALINOS DO LITORAL SUL­BRASILEIRO

ECOLOGICAL DISTRIBUTION OF THECAMOEBINA AND FORAMINIFERA IN MIXOHALINE ENVIRONMENTS ALONG THE SOUTHERN BRAZILIAN LITTORAL

Marly Lopes Madeira (1971)

Adviser: Darcy Closs

Abstract

The southeastern Brazilian coast, comprising Rio Grande do Sul, Santa Catarina and Paraná States, is mainly characterized by a low sandy coastal plain which extends from the oceanic shore line inland to the granitic hills disposed NNE to SSW. The main geographic features of this region are beaches, deltas, estuaries, bays, fresh and mixohaline water lagoons.

Thecamoebian and foraminiferal associations of mixohaline environ-ments of this region, as obtained from samples collected from Chuí (Rio Grande do Sul State) to Paranaguá (Paraná State), were analized. Based on these data, four marginal marine environments were distinguished: lagoons, marshes, bays­estuaries, and beaches.

The main ecological factors considered to be responsible for the distinctive distribution of the associations are salinity, temperature and depth.

CONTRIBUIÇÃO À ESTRATIGRAFIA DO CRETÁCEO DO NORDESTE DO BRASIL, ATRAVÉS DA ANÁLISE PALINOLÓGICA DE PERFURAÇÃO NA FORMAÇÃO JANDAÍRA (RN)

CONTRIBUTION TO THE STRATIGRAPHY OF THE CRETACEOUS OF NORTHEASTERN BRAZIL, BY MEANS OF PALYNOLOGICAL ANALYSIS OF A DRILL CORE FROM THE JANDAÍRA FORMATION (RN)

Maria de Pompéia Correa de Araújo (1971)

Advisers: Irajá Damiani Pinto e Sérgio Archangelsky

Abstract

The palynological study of the stratigraphical drilling BSJ­1­RN, carried out in the region of Macau, Rio Grande do Norte State (northeastern Brazil) is presented. Having analized the stratigraphy and paleontology of the area, a palynological study was made, of which resulted a very poor association composed of 27 species of polens, amongst which one is considered as new and another as Incertae Sedis. The identification of the species with chronological valueled us to calculate their age as between Cenomanian and Turonian, the sediments being related to the lower part of the Jandaíra Formation of the Potiguar Basin.

The absence of microplankton and the abundance of cuticules and of other organic remains indicate a partially closed basin of shallow and moving waters. The predominance of angyospermian grains, the abundance of ephedroids and the absence of pteridophyts suggest a dry climate.

CONTRIBUIÇÃO PALINOLÓGICA À ESTRATIGRAFIA DO CRETÁCEO DO NORDESTE DO BRASIL: ANÁLISE DA PERFURAÇÃO GSB1, SERRA BRANCA, PERNAMBUCO

A PALYNOLOGICAL CONTRIBUTION TO THE CRETACEOUS STRATIGRAPHY OF NORTHEASTERN BRAZIL: ANALYSIS OF THE DRILL CORE GSB1, SERRA BRANCA, PERNAMBUCO STATE

Murilo Rodolfo de Lima (1971)

Advisers: Irajá Damiani Pinto e Sérgio Archangelsky

Abstract

This dissertation represents a first attempt to study the palynology of the Araripe Basin. The palynological content of the studied material is extremely rich and 57 types were selected, described, and identified up to their genus and in some cases up to the species.

Based on statistical analyses, three different zones were identified and each association led to various conclusions. The presence of sometypes with stratigraphic value allowed to determine an Albian age to the whole section. On the other hand, based on the characteristic types, paleogeographic, paleoecological, paleoclimatic, and paleofloristic conclusions were drawn. These conclusions are, however, conditioned by various restrictions, owing to the fact that this is a new area of palynological research.

CONCHOSTRÁCEOS MESOZÓICOS DO SUL DO BRASIL: CONTRIBUIÇÃO À ESTRATIGRAFIA DAS FORMAÇÕES SANTA MARIA E BOTUCATU

MESOZOIC CONCHOSTREACEANS FROM THE SOUTH OF BRAZIL: A CONTRIBUTION TO THE STRATIGRAPHY OF THE SANTA MARIA AND BOTUCATU FORMATIONS

Yoco Katoo (1971)

Adviser: Irajá Damiani Pinto

Abstract

The present dissertation comprises the systematic study of conchostracea which occur in the Santa Maria Formation, Rio Grande do Sul State, Brazil, as well as the comparative study of these fossils with those of the Botucatu Formation, São Paulo State. This work aims to clarify the relative stratigraphic position of the two units. Conchostracea found in the Santa Maria Formation are: Euestheria cf. minuta von Zieten, Euestheria cf. emmonsi (Raymond), Euestheria cf. forbesii (Jones) and species of genera Lioestheria, Pseudoasmussia, Echinestheria?, Estheriina? and Orthothemos?.

Lioestheria sp. comes from the base of the Santa Maria Formation. The other forms come from a new outcrop called here "Belvedere", which is located near the city of Santa Maria, RS. This outcrop is considered to be of a fluvial facies, which is related to the top of the Santa Maria Formation by some authors and to the base of the Botucatu Formation by other authors. The problems involving the position of the sequence are discussed on the basis of the biota. The established correlations between the Santa Maria Formation and the Botucatu Formation are discussed.

MINICYTHERE, GEN.ET SP.NOV. (OSTRACODA) DO SUL DO BRASIL: GÊNEROS AFINS E ASSOCIAÇÕES FAUNÍSTICAS DETERMINANTES DE AMBIENTE MIXOHALINO

MINICYTHERE, N.GEN.ET SP. (OSTRACODA) FROM SOUTHERN BRAZIL. RELATED GENERA AND FAUNISTIC ASSOCIATIONS INDICATIVE OF MIXOHALINE ENVIRONMENT

Lília Pinto de Ornellas (1972)

Adviser: Irajá Damiani Pinto

Abstract

A new ostracode: Minicythere heinii Ornellas, n.gen. et sp. is described. The exhaustive comparison with allied genera resulted in the revalidation of Cushmanidea, Pontocythere, Hemicytherideis and Hulingsina, considered as synonyms by precedent authors. The systematic position of Cytherideis perangusta Zalányi, 1913, its stratigraphic distribution and of the genera above are also discussed. Evidence that the association of the genera Cyprideis, Perissocytheridea, Cytherura, and the new genus Minicythere are excellent indicators of brackish water environment was also established.

NOVAS OCORRÊNCIAS FOSSILÍFERAS DO GRUPO PASSA DOIS DO RIO GRANDE DO SUL

NEW FOSSILIFEROUS OCCURRENCES OF THE PASSA DOIS GROUP IN RIO GRANDE DO SUL

Oscar Rösler (1972)

Adviser: Darcy Closs

Abstract

New fossiliferous occurrences in the Irati and Estrada Nova Formations (Passa Dois Group, Permian), registered for the municipalities of Pinheiro Machado and Bagé (southern region of Rio Grande do Sul State) are discussed.

Remains of Mesoraurus brasiliensis McGregor, crustaceans, fish scales, and fossil plants, besides other indeterminate remains, were found in fine­grained siltstones and calcareous levels pertaining to the Irati Formation in Pinheiro Machado.

The sedimentary sequence outcroping along the Bagé­Aceguá Highway has revealed, for the first time, the presence of Lycopodiopsis in the Irati Formation. The same sequence also revealed, for the first time, the presence of Pinzonella in the sediments of Estrada Nova Formation in Rio Grande do Sul, whereas this bivalvian mollusk is an usual occurrence of Estrada Nova outcrops in other southern Brazilian areas.

The study here developed on the metric relationships of mesosaurian teeth proved to be useful for the identification of isolated pieces.

The São Sepé outcrop, in reference to its geologic age and presence of Calamites, is also commented on.

PALEOECOLOGIA DOS MOLUSCOS CENOZÓICOS DA PLANÍCIE COSTEIRA DO RIO GRANDE DO SUL

PALEOECOLOGY OF CENOZOIC MOLLUSKS FROM THE COASTAL PLAIN OF RIO GRANDE DO SUL

Ieda Regina da Silva Forti (1972)

Adviser: Darcy Closs

Abstract

The paleoecological study of fossil mollusks from the Rio Grande do Sul Coastal Plain drill­holes and outcrops showed, by comparing them with the recent fauna, the existence of a marine environment of shallow water, with fresh­water afflux, during the deposition of these associations. The occurrence of mixohaline species suggests yet a deltaic environment.

O GÊNERO CHLAMYDOTHECA (OSTRACODA) NO BRASIL. TAXINOMIA. OBSERVAÇÕES SOBRE ECOLOGIA, DISTRIBUIÇÃO GEOGRÁFICA E POSIÇÃO ESTRATIGRÁFICA

THE GENUS CHLAMYDOTHECA (OSTRACODA) IN BRAZIL. TAXONOMY. OBSERVATIONS ON ITS ECOLOGY, GEOGRAPHIC DISTRIBUTION AND STRATIGRAPHIC POSITION

Sônia Conceição Bender Kotzian (1972)

Adviser: Irajá Damiani Pinto

Abstract

About thirty two species of the genus Chlamydotheca are known presently. This dissertation deals with the occurrence of the genus in Brazil. This occurrence has demonstrated to be very representative in quantity, since twenty two different species were registered, six of which are new.

In the description of the species the same importance is given to the soft parts and to the morphology of the carapace, what permits to present more data for the systematics of the genus and specially to use them for future comparisons with fossil ostracodes. Ecological aspects, considerations about geographical distribution and stratigraphical position of this group are also discussed.

OSTEOLOGIA CRANIANA DE TEIUS TEYOU TEYOU (LACERTILIA, TEIIDAE)

CRANIAL OSTEOLOGY OF TEIUS TEYOU TEYOU (LACERTILIA, TEIIDAE)

Fumika Takahashi (1972)

Adviser: Carlos de Paula Couto

Abstract

The present dissertation deals with the osteology of syncranium of Teius teyou teyou (DAUDIN, 1802) as well as with the ecological study of this teiid lizard. Tem specimens, collected nearby the cities of Viamão and Porto Alegre, RS, were prepared and described at the Departamento de Paleontologia de Vertebrados do Instituto de Geociências da Universidade Federal do Rio Grande do Sul.

A comparison between the cranial osteology of Teius and Tupinambis is presented.

Many osteological differences were detected, as shown on Table 5. Another conspicuous difference is to be seen in the dentition. Tupinambis exhibits a globularization of the molars, indicating a crushing mechanics during mastigatory activity. The teeth in Teius show a sectorial border, indicating that this form does not include mollusks in its diet.

GEOLOGIA DA REGIÃO DE SANTA VITÓRIA DO PALMAR, RS, E A POSIÇÃO ESTRATIGRÁFICA DOS FÓSSEIS DE MAMÍFEROS PLEISTOCÊNICOS

GEOLOGY OF THE SANTA VITÓRIA DO PALMAR REGION (RS) AND THE STRATIGRAPHIC POSITION OF THE PLEISTOCENE FOSSIL MAMMALS

Enio Soliani Júnior (1973)

Adviser: Carlos de Paula Couto

Abstract

This dissertation intends to solve the problem of the stratigraphic position of pleistocenic mammal fossils found in sediments of the coastal plain near Santa Vitória do Palmar, Rio Grande do Sul, SE Brazil. Geologic and geomorphologic mapping of the meridional portion of the coastal plain has been made by the author. After the deposition processes which originated the Pliocene to Middle Pleistocene Graxaim Formation, the field works showed that the continental margin was affected by three transgressive events. These landward shoreline migrations are supposed to be correlatable to the Aftonian, Yarmouth and Sangamon interglacial periods of the northern hemisphere. To the Aftonian/Kansan, Yarmouth/ Illinoian and Sangamon/Wisconsin limits, i.e., from one interglacial to the immediately following glacial corresponds a regressive event responsible for the generation of conditions to the deposition of lagoonal, fluviatile and eolian sediments which partially cover the shallow marine and beach sediments of the Chuí Formation.

The mammalian fossil remains are preserved in lagoonal sediments represented by green quartzose sands which generally show a gradation to the top to gray organic sands or to peat. These lagoonal sediments along with their fossil content are considered by the author as characteristic of a new lithostratigraphic unit of the coastal plain by him formally defined as Santa Vitória Formation.

Sediments more modern than the Wisconsin do not contain fossils belonging to the considered pleistocenic fauna, and this suggests that the extinction processes, in this area, occurred at the limit between the Upper Pleistocene and the Lower Holocene.

Paleosoil studies indicate that paleoclimatic conditions were uniform during all the Upper Pleistocene time and were developed under steppe environment with mild temperature and humidity, ending with a rapid cool and dry period. This climate favored the growing of an abundant grass and arbustive vegetation, whose roots are preserved in these paleosoils. These paleoenvironment conditions are in agreement with the mammalian ecology.

Based on paleogeographic studies it was possible to interpret the evolution to the present configuration of the coastal province southernmost part and it was also possible to conceive the most probable tectonic behavior of the considered area during the Upper Pleistocene.

CONTRIBUIÇÃO À PALINOLOGIA DA FORMAÇÃO IRATI (PERMIANO), RIO GRANDE DO SUL, BRASIL

CONTRIBUTION TO THE PALYNOLOGY OF THE IRATI FORMATION (PERMIAN), RIO GRANDE DO SUL, BRAZIL

Julieta Gisselda Dellazzana (1973)

Advisers: Irajá Damiani Pinto e Sérgio Archangelsky

Abstract

In this dissertation the microspore association from Irati Formation, Rio Grande do Sul State, Brazil, considered to be of Permian age, is systematically described.

Sixteen species are described, four of which are new: Convolutispora pintoi, Protohaploxypinus labratus, Piceapollenites archangelskyi and Lueckisporites iratiensis.

Based on the comparison of this association with other Gondwanic miospore associations, an Upper Permian age was assigned to the Irati Formation.

ESTUDO PALINOLÓGICO DE CONCREÇÕES CALCÁRIAS DA FORMAÇÃO SAN GREGÓRIO, NE DA REPÚBLICA ORIENTAL DEL URUGUAY - BACIA DO PARANÁ

PALYNOLOGICAL STUDY OF CALCAREOUS CONCRETIONS OF THE SAN GREGORIO FORMATION, NORTHWEST OF THE ORIENTAL REPUBLIC OF URUGUAY - PARANÁ BASIN

Marleni Marques Toigo (1973)

Advisers: Irajá Damiani Pinto e Sérgio Archangelsky

Abstract

The present dissertation deals with the systematic study of dispersed spores and pollen grains found in phosphoric concretions which contain ammonoids, in the lower part of the glacial deposits of San Gregorio Formation in northern Uruguay (equivalent to the Itararé Sub­Group from Paraná Basin).

That formation is considered to be of Upper Carboniferous age; nevertheless, and taking into consideration the results of the palynological analyses here presented, the author's opinion is to consider it of Lower Permian age.

The palynological assemblage comprises 27 genera and 59 species. One genus and eleven species are new.

The plant microfossils show a great affinity to those previously described from the Lower Gondwana rocks of Australia, South Africa, India, Bolivia and Brazil.

A OCORRÊNCIA DO GÊNERO POLYSOLENOXYLON NA FORMAÇÃO IRATI DO RIO GRANDE DO SUL

THE OCCURRENCE OF THE GENUS POLYSOLENOXYLON IN THE IRATI FORMATION, RIO GRANDE DO SUL

Margot Guerra (1973)

Adviser: Klaus Ulrich Leistikow

Abstract

A new species of a petrified gymnosperm wood, Polysolenoxylon bageense n.sp., is described. It is represented by a fragment collected by Prof. Carlos Alfredo Bortoluzzi in an outcrop situated at the sides of the Bagé-Hulha Negra highway, Rio Grande do Sul State, Brazil, whose sediments belong to the Permian IratiFormation of the gondwanic sequence (Paraná Basin).

The finding of this fossil wood permitted to establish the paleogeographic distribution of the genus and to confirm its stratigraphic position.

BAGEOPITYS ARTICULATA GEN. ET SP. NOV., MADEIRA FÓSSIL DE GIMNOSPERMA DA FORMAÇÃO IRATI, RIO GRANDE DO SUL, BRASIL

BAGEOPITYS ARTICULATA N.GEN. AND N.SP., A NEW GYMNOSPERMIAN FOSSIL WOOD FROM THE IRATI FORMATION, RIO GRANDE DO SUL, BRAZIL

Maria Helena Ribeiro Hessel (1973)

Adviser: Klaus Ulrich Leistikow

Abstract

The specimen here described was collected in an outcrop of the Valente Facies (Irati Formation, Permian), on the highway Bagé­Aceguá, at a site 10km south of Bagé, municipality of Bagé, Rio Grande do Sul State, southern Brazil. It was included in the characteristic dark gray shales of the above­mentioned facies. Determined as Bageopitys articulata n. gen., n. sp., it was well preserved and allowed a detailed morpho­anatomical observation of its pith and the primary and secundary xyleme structures. Though presenting particular characteristics, the specimen exhibits anatomic features (such as "araucaroid" to "mixed" radial punctuations) which are frequently observed among Permo­Carboniferous Gondwanic woods. A comparative survey on Gondwanic woods is also presented.

BARAKAROXYLON BRASILIENSE SP.NOV. - MADEIRA FÓSSIL DA FORMAÇÃO IRATI, RIO GRANDE DO SUL, BRASIL

BARAKAROXYLON BRASILIENSE, SP.NOV. - A FOSSIL WOOD OF THE IRATI FORMATION, RIO GRANDE DO SUL, BRAZIL

Claudete Schrage (1973)

Adviser: Klaus Ulrich Leistikow

Abstract

A fragment of silicified wood found in continental sediments of the Irati Formation (Rio Grande do Sul State, Brazil) permitted the establishment of a new species: Barakaroxylon brasiliense, n.sp.

Owing to anatomical characteristics, particularly those of the pith, it was possible to define generic affinities in relation to a gondwanic species occurring at the Kungurian Baraker horizon of India.

A revision of the species Dadoxylon lafoniense Halle 1925 is also presented. Based on the analysis of the descriptions made by the above­mentioned author, the obtained data led to the identification of this species under a new combination: Barakaroxylon lafoniense (Halle), n.comb.

The geographic and stratigrapahic distributions of certain elements of the Permian flora in the Southern Hemisphere allowed the correlation between the different floristic provinces of the Gondwana.

ESTUDO DE ESCAMAS E DENTES DE PEIXES DA FÁCIES BUDÓ, SUBGRUPO ITARARÉ - RS

STUDY OF THE SCALES AND TEETH OF FISHES FROM THE BUDÓ FACIES, ITARARÉ SUB­GROUP - RS

Marlene Terezinha Barcellos (1973)

Adviser: Irajá Damiani Pinto

Abstract

This dissertation presents the results obtained from the study of thin sections of internal structures of teeth and scales of marine fishes from the Budó Facies, Itararé Sub­Group, in Rio Grande do Sul State. Informations on the stratigraphy of the studied sediments are also dealt with.

The revision of the paleofauna led, for the first time, to the description of Elasmobranchia teeth, scales and teeth of Crossopterygii (Actinistia) and scales of Paleoniscoidei. Three geologic profiles developed at the Budó, Acampamento Velho and Cambaí Grande outcrops provided stratigraphic correlations based on lithologic, structural and paleontologic characteristics.

The studies carried on evidenced that the Budó and Acampamento Velho outcrops share a clear identity of their characteristics, whereas the characteristics of the Cambaí Grande outcrop are substantially distinctive.

TAXONOMIA E RELAÇÕES DOS PROGANOSAURIA DA BACIA DO PARANÁ

TAXONOMY AND RELATIONSHIPS OF THE PROGANOSAURIA OF THE PARANÁ BASIN

Dina Celeste Araújo (1974)

Adviser: Carlos de Paula Couto

Abstract

The present dissertation deals mainly with the taxonomy of the Proganosaurian reptiles which occur in the Irati Formation (Permian, Paraná Basin). The ordinal name Proganosauria, as proposed by Baur (1887) and including the genus Stereosternum, is adopted in this research, by reasons of priority, instead of Mesosauria. The order includes a single family, Mesosauridae.

The precarious conditions of preservation determined that rather than a purely osteological analysis, the material should also be studied under a statistical approach. As it was well known by the time this study started, previous osteological contributions did not lead to sufficiently explanatory conclusions from a taxonomical point of view. Nevertheless, osteology was kept as an important set of data for basing the statistical procedures.

Upon the analysis of 79 specimens, the following conclusions were reached:

a) the Proganosauria of the Paraná Basin are represented by three species: Stereosternum tumidum Cope 1886, Mesosaurus brasiliensis MacGregor 1908 and Brazilosaurus sanpauloensis Shikama & Ozaki 1966;

b) those forms had an endemic ancestor, what caused the restricted geographic distribution of the group (South America and Africa);

c) phylogenetic distance from the ancestor is not very great, as it can be testified by the similarities of morphologic and structural characteristics shared by all known proganosaurs;

d) on the other hand, some marked adaptations for feeding (M. brasiliensis) and water locomotion (B. sanpauloensis) suggest a rapid evolution;

e) M. brasiliensis lived in a larger geographic area, nowadays equivalent to Rio Grande do Sul, Santa Catarina and Paraná States (Zone A), whereas S. tumidum and B. sanpauloensis occupied a more restricted region, corresponding to São Paulo State (Zone B).

O QUATERNÁRIO DA ÁREA DO RIO PARDO - RIO GRANDE DO SUL

THE QUATERNARY OF THE RIO PARDO AREA - RIO GRANDE DO SUL

Tânia Lindner Dutra (1974)

Adviser: Carlos de Paula Couto

Abstract

This dissertation is a first attempt to characterize the inner sedimentary Quaternary areas of Rio Grande do Sul State, Brazil, using as a model a part of the middle portion of the Rio Pardo valley, where the following aspects were identified:

1. there were predominantly warm, semi­arid climatic conditions alternated with humid periods, from the final part of the Tertiary up to the beginning of the Pleistocene (Nebraskan­Aftonian limit), what led to the formation of flattened surfaces and their correlated terrace levels with gravels, at least under two complete cycles;

2. a gradual passage to more humid climates occurred, establishing a steppe­like climate in the region, which lasted until the final period of the Pleistocene. Two low terraceswith gravels, covered with paleosoils and related to the variations of the Rio Pardo local base were formed;

3. the present climates, with the formation of less expressive terraces without paleosoil cover, also associated with local variations of the base level in the drainage network.

Similar events, which occurred in other parts of Brazil and on the coastal regions of the State, can be correlated with those present within the studied area.

Although, non­correlation was observed concerning the duration of the more severe climates, which originated the oldest flat surfaces and their correlative deposits, between the events here described and those occurred outside the State of Rio Grande do Sul.

PALEONTOLOGIA E ESTRATIGRAFIA DO PLEISTOCENO CONTINENTAL DO NORDESTE BRASILEIRO - "FORMAÇÃO CACIMBAS"

PALEONTOLOGY AND STRATIGRAPHY OF THE CONTINENTAL PLEISTOCENE OF BRAZILIAN NORTHEAST - "CACIMBAS FORMATION"

José Lins Rolim (1974)

Adviser: Carlos de Paula Couto

Abstract

This dissertation presents an overall analysis of the continental Quaternary sequence of northeastern Brazil, by means of a paleontological, stratigraphical and sedimentological study of the descontinuous Pleistocene deposits represented by"tanks" and small lagoons, assigned to the "Cacimbas Formation". It is thus aimed to present an interpretative account on the paleogeographic, paleoclimatic and paleoecological features of the northeastern Brazilian Pleistocene.

POSIÇÃO ESTRATIGRÁFICA DO CALCÁRIO MIRIRI, PARAÍBA, BRASIL

THE STRATIGRAPHIC POSITION OF THE MIRIRI LIMESTONE, PARAÍBA, BRAZIL

Vilma Alves Campanha (1974)

Adviser: Irajá Damiani Pinto

Abstract

Petrographic and paleontological studies were made on the Miriri limestone situated in the Rio Tinto municipality, Paraíba State. Field work and the results obtained in the laboratory confirmed a Maastrichtian age and determined the paleoecology of the limestone, which constitutes the most northerly extension of the Pernambuco - Paraíba sedimentarycoastal basin. Stratigraphically, the Miriri limestone belongs to the limestone lithofacies of the Gramame Formation, however representing a new biofacies.

For stratigraphical correlation similar studies were made on the nearby Oiteiros limestone in Canguaretama, Rio Grande do Norte State.

ESTUDO PALINOLÓGICO DO SUBGRUPO ITARARÉ, NA "COLUNA WHITE". PERMIANO INFERIOR, SANTA CATARINA

PALYNOLOGICAL STUDY OF THE SUB­GROUP ITARARÉ IN "WHITE'S COLUMN". LOWER PERMIAN - SANTA CATARINA

Maria Elisabeth Happel Pons (1975)

Adviser: Irajá Damiani Pinto

Abstract

Palynological studies of the sandstones and shales of the Itararé Sub­group at "White's Section", of Lauro Müller, Santa Catarina, revealed a large variety of miospores in the assemblage, with Trilete, Monosaccite, Disaccite, Striatiti, Monocolpate, Praecolpate, Polyplicate forms and Incertae sedis.

The assemblage comprises 53 species, one of which is new, Neoraistrickia baculicapillosa, sp. nov.

Trilete forms constitute 70% of the palynological content, mainly the genera Punctatisporites, Granulatisporites, Deltoidospora and Calamospora. Pollenite forms and Incertae sedis are the other components of the assemblage.

Among Pollenite group, Monosacate forms dominate in the palynological assemblage. The genera Cordaitina, Potoniesporites and Virkkipollenites are well represented.

Striatiti (Protohaploxypinus, Striatopodocarpites, Lueckisporites and Vittatina) are poorly represented in the assemblage.

Palynological content analysis suggests a Lower Permian age, probably Sakmarian, for the Itararé Subgroup in the studied area, based on correlations with other Gondwanic miospores assemblages.

ICHTIODONTES E ICHTIODORULITOS (PISCES) DA FORMAÇÃO ESTRADA NOVA E SUA APLICAÇÃO NA ESTRATIGRAFIA DO GRUPO PASSA DOIS

ICHTHIODONTS AND ICHTHIODORULITHS (PISCES) FROM THE ESTRADA NOVA FORMATION AND THEIR STRATIGRAPHIC UTILIZATION IN THE PASSA DOIS GROUP

Norma Luiza Würdig Maciel (1975)

Adviser: Irajá Damiani Pinto

Abstract

This dissertation introduces, for the first time in Brazil, a methodology for the utilization of ichthyodonts, ichthyodoruliths and fish scales in stratigraphical and paleoecological studies. This study was made mainly with material collected in the Permian Estrada Nova and Irati Formations; the specimens from the first were more numerous.

The use of this material demanded the utilization of two types of systematics: the natural systematics and another one, artificial, specially conceived for stratigraphical purposes and based on morphologic patterns of Palaeoniscid teeth, not easily adjustable to the natural systematics procedures.

According to the natural systematics, three new species of Elasmobranchiomorphi were described: Xenacanthus santosi Würdig­Maciel, n. sp. and Orodus milleri Würdig­Maciel, n. sp. from Estrada Nova Formation; Xenacanthus pricei Würdig­Maciel, n. sp. was collected in Irati Formation.

A typical association was determined for each formation indicating a sub­aqueous environment with low salinity at the beginning of the sedimentation, changing to a continental fresh­water environment at the end of it.

The sediments corresponding to the Irati Formation and the beginning of the Estrada Nova Formation have been already dated as Ufimskian to Kazanian, based on the flora and fauna. The upper part of the Estrada Nova Formation could reach the Tatarian.

O GÊNERO UVIGERINA (FORAMINIFERIDA) DO CENOZÓICO SUPERIOR NA BACIA DE PELOTAS, RIO GRANDE DO SUL, BRASIL

THE UPPER CENOZOIC GENUS UVIGERINA (FORAMINIFERIDA) IN THE PELOTAS BASIN, RIO GRANDE DO SUL, BRAZIL

Jane Maria Garrafielo Fernandes (1975)

Advisers: Alwine Bertels e Irajá Damiani Pinto

Abstract

In the present dissertation fossil foraminifera pertaining to the genus Uvigerina are described from drill holes made by PETROBRÁS at Cassino and Mostardas in the Pelotas Basin, Rio Grande do Sul State, Brazil. Four informal and correlatablebiostratigraphic zones could be delimited in both drill holes. The age of the sedimentary sequences and the ecologic factors which conditioned the distribution of the genus Uvigerina were discussed for both drill holes.

BOLIVINITIDAE E CAUCASINIDAE (FORAMINIFERIDA) DO CENOZÓICO SUPERIOR DA BACIA DE PELOTAS, RIO GRANDE DO SUL, BRASIL

BOLIVINITIDAE AND CAUCASINIDAE (FORAMINIFERIDA) FROM THE UPPER CENOZOIC OF PELOTAS BASIN, RIO GRANDE DO SUL, BRAZIL

Zoah Valladão Thiesen (1975)

Advisers: Alwine Bertels e Irajá Damiani Pinto

Abstract

This dissertation deals with the taxonomic study of fossil species of the families Bolivinitidae and Caucasinidae. The material was supplied by PETROBRÁS and obtained from two drill holes (Cist­1­RS and Most­1­RS) from Pelotas Basin, State of Rio Grande do Sul, Brazil. Three informal biostratigraphic zones wereestablished and could be correlated in both drill holes. The geographic and stratigraphic worldwide distribution of the species studied is analyzed; geological ages for the sedimentary sequences concerned are proposed and paleoecological and paleoclimatic considerations suggested.

ESTUDO PALINOLÓGICO DA JAZIDA CARBONÍFERA DE CHARQUEADAS, RIO GRANDE DO SUL, BRASIL

PALYNOLOGICAL STUDY OF THE CHARQUEADAS COALFIELD, RIO GRANDE DO SUL, BRAZIL

Maria Ieda de Almeida Burjack (1976)

Adviser: Irajá Damiani Pinto

Abstract

The present dissertation deals with the palynological study of the Charqueadas Coalfield, MB, I1B and I2B seams in Rio Grande do Sul, Brazil.

The assemblage comprises 44 genera and 77 species, two which are new: Sulcatisporites minimus n. sp. and Sulcatisporites medius n. sp.

With the study of the sporopollinical assemblage, the palynological features of each seam were established.

The comparison of the studied material with other regions of the Gondwana showed that it belongs to the Artinskian­Kungurian, Lower Permian age. Paleoecological interpretation was attempted for each coal seam.

OSTEOLOGIA PÓS­CRANIANA DE TUPINAMBIS TEGUIXIN (L., 1758) SENSU BOULENGER, 1885 (LACERTILIA, SCINCOMORPHA, TEIIDAE)

POST­CRANIAL OSTEOLOGY OF TUPINAMBIS TEGUIXIN (L., 1758) SENSU BOULENGER, 1885 (LACERTILIA, SCINCOMORPHA, TEIIDAE)

Lígia Krause (1976)

Adviser: Mario C. Barberena

Abstract

The present dissertation deals with the post­cranial osteology of Tupinambis teguixin (L., 1758) sensu Boulenger, 1885, in continuation to the paper by Barberena, Gomes & Sanchotene (1970), in which its cranial osteology was described.

Two specimens, collected in Aparados da Serra, State of Rio Grande do Sul, were put to death and prepared; the skeletons werenumbered ZOO 001, a male, and ZOO 002, a female. The latter, being older, was chosen as the main material for descriptive purposes.

Detailed osteological description is here emphasized, rather than biomechanic or morpho­taxonomic aspects. Those subjects will be dealt with by the author in further studies.

MODELO PALEOECOLÓGICO­EVOLUTIVO PARA O NEO­QUATERNÁRIO DA REGIÃO DA CAMPANHA­OESTE DO RIO GRANDE DO SUL (BRASIL). A FORMAÇÃO TOURO PASSO, SEU CONTEÚDO FOSSILÍFERO E A PEDOGÊNESE PÓS­DEPOSICIONAL

PALAEOECOLOGICAL­EVOLUTIONARY MODEL FOR THE LATE QUATERNARY OF THE CAMPANHA­OESTE REGION OF RIO GRANDE DO SUL (BRAZIL). THE TOURO PASSO FORMATION, ITS FOSSIL CONTENT AND POST­DEPOSITIONAL PAEDOGENESIS

Miguel Bombim Gomes (1976)

Adviser: Carlos de Paula Couto

Abstract

A multidisciplinary study of the last 15,000 years record of the Arroio Touro Passo Basin (Uruguaiana - RS - Brazil) is made by using geomorphological, stratigraphical, sedimentological, paedological, paleontological, archaeological and radiocarbon dates criteria.

A new formation (Touro Passo Formation) is proposed as well as fiveclimatic phases, beginning at the end of the last glacial period. A model to explain those changes based on atmospheric circulation is presented.

Other noteworthy ecological facts have also occurred in the area even in this geologically short period, such as megafaunal extinctions and the arrival of Man.

OSTEOLOGIA CRANIANA DE AMPHISBAENA DARWINI TRACHURA COPE, 1885. (LACERTILIA, AMPHISBAENIDAE)

CRANIAL OSTEOLOGY OF AMPHISBAENA DARWINI TRACHURA COPE, 1885. (LACERTILIA, AMPHISBAENIDAE)

Marisa Ibarra Vieira (1977)

Adviser: Carlos de Paula Couto

Abstract

The present research deals with the detailed description of the bones that form the skull and jaw of Amphisbaena darwini trachura COPE, 1885, found in Brazil (from São Paulo to Rio Grande do Sul), north of Uruguay and extreme northeast of Argentina.

The study was based upon the examination of five specimens, all of them from Rio Grande do Sul, deposited in the Collection of the Museu de Ciências Naturais of the Fundação Zoobotânica do Rio Grande do Sul.

ESTUDO OSTEOLÓGICO COMPARATIVO DO CRÂNIO DE HEMIDACTYLUS MABOUIA (MOREAU DE JONNES, 1818) E HOMONOTA URUGUAYENSIS (VAZ­FERREIRA & SIERRA DE SORIANO, 1961). LACERTILIA, GEKKONIDAE

COMPARATIVE OSTEOLOGICAL STUDY OF THE SKULL OF HEMIDACTYLUS MABOUIA (MOREAU DE JONNES, 1818) AND HOMONOTA URUGUAYENSIS (VAZ­FERREIRA & SIERRA DE SORIANO, 1961). LACERTILIA, GEKKONIDAE

Marta Elena Fabián Beurmann (1977)

Adviser: Carlos de Paula Couto

Abstract

Based upon the examination of six specimens of Hemidactylus mabouia (MOREAU DE JONNES, 1818) and of Homonota uruguayensis (VAZ­FERREIRA & SIERRA DE SORIANO, 1961), a comparative description of their cranial osteology is presented. Differences are analyzed from the point of view of the form and proportion of thebones. This research is complemented by a statistical analysis through the application of the t test, aiming at establishing the significant differences among certain cranial structures of the two species. Finally, there is a brief comparison between the obtained results and the data presented by KLUGE (1967).

OSTEOLOGIA CRANIANA DE OPHIODES STRIATUS (SPIX, 1824) (LACERTILIA, ANGUIDAE)

CRANIAL OSTEOLOGY OF OPHIODES STRIATUS (SPIX, 1824) (LACERTILIA, ANGUIDAE)

Maria Lúcia Machado Alves (1977)

Adviser: Carlos de Paula Couto

Abstract

This dissertation aims to contribute to the knowledge of the cranial osteology of Ophiodes striatus (Spix, 1824) and to supply data for future comparative studies with other lizard species.

Six skulls of specimens that belong to the reptilian collection of the Museu de Ciências Naturais, Fundação Zoobotânica do Rio Grande do Sul, were prepared and incorporated to that collection as osteological samples.

OSTEOLOGIA CRANIANA DE BRADYPUS LINNAEUS, 1758 E REVALIDAÇÃO DO GÊNERO SCAEOPUS PETERS, 1865 (EDENTATA - BRADYPODIDAE)

CRANIAL OSTEOLOGY OF BRADYPUS LINNAEUS, 1758 AND THE REVALIDATION OF THE GENUS SCAEOPUS PETERS, 1865 (EDENTATA - BRADYPODIDAE)

Tânia Maria Silveira Santos (1977)

Adviser: Carlos de Paula Couto

Abstract

The present dissertation deals with the osteological description of the skull of Bradypus Linnaeus 1758, a living tridactyl sloth.

Four specimens from the Museu Nacional, Rio de Janeiro, were examined and compared to one another and it was noticed that they could be divided into two distinct groups, probably corresponding to two different genera.

A comparison, in general terms, was made among these genera and other living and fossil Edentata of the Megatheria infra­order.

OSTEOLOGIA CRANIANA E ODONTOLOGIA DE CHRYSOCYON BRACHYURUS (ILLIGER, 1815)

CRANIAL OSTEOLOGY AND ODONTOLOGY OF CHRYSOCYON BRACHYURUS (ILLIGER, 1815)

João Francisco Peixoto Pereira (1977)

Adviser: Carlos de Paula Couto

Abstract

This dissertation deals with the study of the cranial osteology and osteometry of Chrysocyon brachyurus and a detailed analysis of its teeth. It is also a contribution to thenomenclature of osseous anatomy and of odontology, allowing to make comparisons with other recent and extinct representatives of the Canidae family.

NODOSARÍDEOS DA PLATAFORMA CONTINENTAL BRASILEIRA : TAXONOMIA - DISTRIBUIÇÃO BATIMÉTRICA

NODOSARIDS OF THE BRAZILIAN CONTINENTAL SHELF: TAXONOMY - BATHYMETRIC DISTRIBUTION

Itamar Ivo Leipnitz (1978)

Adviser: Ivan de Medeiros Tinoco

Associated Adviser: Yvonne T. Sanguinetti

Abstract

This dissertation deals with the taxonomic study of recent nodo-sarideans (Foraminiferida) gathered out of six oceanographic campaigns on the Brazilian Continental Shelf, conducted by "Laboratório de Ciências do Mar" of Pernambuco Federal University. 48 species were classified, including a new species and a new form: Lingulinopsis tinocoi n. sp. and Dentalina communis (d'Orbigny), f. microestriolata n.f. Bathymetric data are also presented.

ESTUDO DA TAPOFLÓRULA DO MEMBRO MORRO PELADO NA SUA LOCALIDADE­TIPO

STUDY OF THE MORRO PELADO MEMBER TAPHOFLORULE IN ITS TYPE­LOCALITY

Miriam Cazzulo Klepzig (1978)

Adviser: Irajá Damiani Pinto

Associated Adviser: Oscar Guillermo Arrondo

Abstract

This dissertation presents a systematic study of the taphoflora from an outcrop of the Morro Pelado Member, Rio do Rasto Formation (Upper Permian), Santa Catarina State, Brazil.

This outcrop, from White's (1908) type­section for the "Santa Catarina System", presents 1­4m "finning­up" cyclothems, that were analized using the Markov chain matrices. The cycles start with a diastem followed by sandstone, siltstone and claystone.

The paleoflora association shows characteristics of a Glossopteris flora, poor in Gondwana elements, with many nordic forms. It is composed of Sphenophyta, Filicophyta, Pteridophylla, Glossopteridophyta and Cordaitophyta.

Two new species have been identified: Pecopteris opposita and Dizeugotheca bortoluzzii. The latter belongs to a not yet registered genus in Brazilian taphofloras.

Some forms, such as Schizoneura gondwanensis, Feismantel have also been identified.

The studied taphoflora is closely related to the Raniganj Flora (Upper Damuda Series, India) and to the flora associated with the Lower Beaufort Series, Africa. It is correlated with the paleofloristic assemblages deposited between the end or the Kazanian and the basal part of the Tatarian.

The taphoflora of the Morro Pelado Member, concerning the floristic sequence of the Paraná Basin, is situated in a biostratigraphic interval equivalent to the Taphoflora E interval (Rösler, 1975).

Based on the paleobotanic and paleoclimatic evidences and on the sedimentologic data, a fluvial palaeonvironment, with flood plain deposits and meandering river channels, with the presence of a cyclic climate, probably temperate, is suggested.

TAIASSUÍDEOS DO PLEISTOCENO DE CAVERNAS CALCÁRIAS DE MINAS GERAIS

TAIASSUYDS FROM THE PLEISTOCENE OF CALCAREOUS CAVES IN MINAS GERAIS

José Sílvio Fonseca (1979)

Adviser: Carlos de Paula Couto

Abstract

This dissertation deals with a comparative and revisional description of the fossil and/or sub­fossil Tayassuidae from the caves of the karstic region of Lagoa Santa ("sensu lato"), Minas Gerais, already described by Reinhardt (1880) and Winge (1906), partially restudied by Rusconi (1930 and 1948) and Wetzel (1977b), and of new and important specimens from the same region, some of them already studied by the latter (op. cit.).

Rusconi's (1948) reclassification of Platygonus (Brasiliochoerus) stenocephalus, as Brasiliochoerus steocephalus, is here ratified, and Platygonus (Parachoerus) carlesi Rusconi, 1930 (= Catagonus carlesi, Wetzel, 1977b) is considered as an absolute synonym of Brasiliochoerus stenocephalus. Three skulls of peccaries, previously included by Wetzel (op. cit.) in Platygonus, are reclassified; two of them are recognized as being from Tayassu pecari, and the third is included in Brasiliochoerus stenocephalus.

SOBRE UM EDENTATA MILODONTIDAE DO PLEISTOCENO - SUB­RECENTE DA BAHIA, BRASIL

ON A MILODONT EDENTATE OF PLEISTOCENE/SUB­RECENT AGE FROM BAHIA, BRAZIL

Cástor Cartelle Guerra (1979)

Adviser: Carlos de Paula Couto

Abstract

This dissertation is dedicated to the description and comparison of the radius, the bones of the hand and part of the foot of a Glossotherium, found in a cave near the town of Morro do Chapéu (Bahia). The osteological description is specially emphasized owing to a lack of papers in Portuguese on the subject.

After a detailed comparative study, it is suggested the revalidation of the subgenus Ocnotherium Lund, 1842, which is an intertropical form of the genus Glossotherium Owen, 1840. Our classification in based on that established by Hoffstetter in 1952.

Concluding by the non­specifical and subgenerical identity of theLagoa Santa form with Argentinean ones, we prefer, for the time being, to identify specifically the form we describe here as the same one whose pieces Lund collected in Lagoa Santa, and Winge studied in 1915. The non­presence of similar skeletal elements in the Lagoa Santa collection similar to those here described does not permit us a direct comparison between our material and that known in Lagoa Santa. This, however, should not pose a problem to us to conclude that the elements above described can be considered as belonging to the same species of milodontids. This assumption is based on the fact that both materials come from the same geographical region, in similar ecological "habitat".

GASTRÓPODES CENOZÓICOS DO ALTO AMAZONAS (ESTADO DO AMAZONAS), BRASIL

CENOZOIC GASTROPODS FROM THE UPPER AMAZON (AMAZONAS STATE), BRAZIL

Elinalda Veríssimo Costa (1979)

Adviser: Irajá Damiani Pinto

Associated Adviser: Cândido Simões Ferreira

Abstract

This dissertation consists of a study of the Cenozoic gastropods found on and under the surface of the clay sediments of the Pebas Formation, Upper Amazon, Brazil.

The faunule consists of five genera, seven species with predominance of Hydrobia ortoni (GABB, 1868).

The association is similar to that of Pebas, Old Pebas and Iquitos atOriental Peru, Canamá and Três Unidos, Upper Amazon, Brazil.

It has been recorded, for the first time, the occurrence of Pliocene gastropods at Atalaia do Norte, Poreré and Tamanduá at the State of Amazon, establishing a larger geographic extension for the Pebas Formation over the Brazilian Territory.

BRAQUIÓPODES DEVONIANOS DO AFLORAMENTO TOPE DE FITA - CHAPADA DOS GUIMARÃES - MATO GROSSO - BRASIL

DEVONIAN BRACHIOPODS FROM THE TOPE DE FITA OUTCROP - CHAPADA DOS GUIMARÃES - MATO GROSSO - BRAZIL

Raquel Quadros (1979)

Adviser: Irajá Damiani Pinto

Associated Adviser: Ivone Purper

Abstract

The present dissertation deals with the Devonian brachiopod fauna of the Tope de Fita outcrop, in the municipality of Chapada dos Guimarães, Mato Grosso State, Brazil.

The fauna has inarticulate and articulate brachiopods: Orbiculoidea baini, Australocoelia tourteleti, Plicoplasia planoconvexa (?); some specimens of indeterminate speriferids, Derbyina sp., Paranaia sp., and some indeterminate specimens of Te-rebratulina and Australostrophia sp. (?). It also records the presence of a new genus for the Family Mutationelina - Chapadella mendesi.

The presence of P. planoconvexa (?) is recorded here for the first time for the Chapada dos Guimarães region.

Some reference has also been made to the various types of preservation of the material.

REVISÃO SISTEMÁTICA DE ALGUNS GÊNEROS RECENTES DA SUBFAMÍLIA BAIRDIINAE (OSTRACODA) DA COSTA BRASILEIRA

SYSTEMATIC REVISION OF SOME RECENT GENERA OF THE SUBFAMILY BAIRDIINAE (OSTRACODA) FROM THE BRAZILIAN COAST

Maria Rotraut Conter (1979)

Adviser: Yvonne Therezinha Sanguinetti

Abstract

A systematic review of recent species of the Subfamily Bairdiinae Sars, 1888, is made, an the affinities and the validity of the genera Bairdia, Neonesidea, Paranesidea, Triebelina, Glyptobairdia and Bairdoppilata are discussed. Special attention is given to the genus Bairdia.

The samples were collected by the Oceanografic Ship (Noc) "Almirante Saldanha", during the Geomar III, in the Amazonic Region, between Cape Orange and Salinópolis.

CONTRIBUIÇÃO AO ESTUDO PALEOXILOLÓGICO DA FORMAÇÃO IRATI DO RIO GRANDE DO SUL

CONTRIBUTION TO THE PALEOXYLOLOGICAL STUDY OF THE IRATI FORMATION IN RIO GRANDE DO SUL

Sheila Mattos Monteiro (1979)

Adviser: Mario C. Barberena

Associated Adviser: Margot Guerra-Sommer

Abstract

This dissertation deals with the description of the anatomic structure of four species of Gondwanic fossil gymnosperm woods from the Irati Formation (Permian of the Paraná Basin), collected in São Gabriel (Rio Grande do Sul State) and Rio Claro (São Paulo State).

The fossil material includes remains of permineralized trunks with excellent conditions of preservation.

The new genera and species are based on the observation of anatomic features not yet related to gondwanicspecimens. The analysis of these features and their comparison with fossil and recent plants supplies subsidies for inference of paleoecologic and paleoclimatic data. At the same time, suggests the establishment of phylogenetic and evolutionary inter­relations.

For this reason four more form­ ­genera are associated with the assembly already described, what provides indicative data on the diversity of gymnosperm plants in the Brazilian gondwanic flora.

UM NOVO CINODONTE CARNÍVORO (PROBELESODON KITCHINGI, SP.NOV.) DO TRIÁSSICO DO RIO GRANDE DO SUL, BRASIL

A NEW CARNIVOROUS CYNODONT (PROBELESODON KITCHINGI, N.SP.) FROM THE TRIASSIC OF RIO GRANDE DO SUL, BRAZIL

Ana Maria Sá Teixeira (1979)

Adviser: Mario C. Barberena

Abstract

The present dissertation deals with the osteological description of the skull of Probelesodon kitchingi n.sp., a new chiniquodontid cynodont from the Santa Maria Formation, Triassic of southern Brazil.

The new species presents significant differential features in relation to P. lewisi and P. minor, from the Chañares Formation of Argentina, such as: a) a longer skull, with less flaring zygomatic arches and longer temporal region; b) different proportions of the maxillae and palatines in the secondary palate and c) 10 instead of 9 (or 8) maxillary postcanines.

Additional differences are to be found in the comparison of individual bones; the main differences have been incorporated in the specific diagnosis.

Probelesodon kitchingi fits adequately the fossil content of the Therapsida Assemblage zone, and occupies the lower levels of the Santa Maria Formation, of Upper Chañarense age.

OSTEOLOGIA DO CRÂNIO E MANDÍBULA DE CERATOPHRYS AURITA (RADDI, 1823), (ANURA, ACOSMANURA, LEPTODACTYLIDAE, CERATOPHRYNAE)

OSTEOLOGY OF THE SKULL AND LOWER JAW OF CERATOPHRYS AURITA (RADDI, 1823), (ANURA, ACOSMANURA, LEPTODACTYLIDAE, CERATOPHRYNAE)

Stela Máris Pires Gayer (1980)

Adviser: Mario C. Barberena

Abstract

The present dissertation deals with the osteological description of the skull and lower jaw of Ceratophrys aurita (Raddi, 1823) (Anura, Acosmanura, Leptodactylidae, Ceratophryinae).

Three specimens were studied. A male and a female collected atLinhares, State of Espírito Santo, and a female collected at Parelheiros, State of São Paulo, were put to death and sent to us by Prof. Werner C.A. Bockermann. The skull of the female of Linhares was chosen as the main material for descriptive purposes.

OSTEOLOGIA CRANIANA DE LAMA GUANICOE (MÜLLER, 1776) EM ESTUDO COMPARATIVO COM CAMELOPS HESTERNUS (LEIDY, 1873)

CRANIAL OSTEOLOGY OF LAMA GUANICOE (MÜLLER, 1776) IN COMPARISON TO CAMELOPS HESTERNUS (LEIDY, 1873)

Christina Teixeira Guimarães Gresele (1980)

Adviser: Carlos de Paula Couto

Abstract

This paper deals with the osteological description of the syncranium of Lama FRISCH, 1775, particularly Lama guanicoe MÜLLER, 1776, in comparison to the extinctgenus Camelops LEIDY, 1854, and the respective type species, C. hesternus (LEIDY, 1873), as described by Webb (1965).

CONODONTES ORDOVICIANOS DA FORMAÇÃO SAN JUAN, PRECORDILLERA, DEPARTAMENTO JACHAL, PROVÍNCIA SAN JUAN, REPÚBLICA ARGENTINA

ORDOVICIAN CONODONTS OF THE SAN JUAN FORMATION, PRECORDILLERA, JACHAL DEPARTMENT, SAN JUAN PROVINCE, REPUBLIC OF ARGENTINA

Valesca Brasil Lemos (1980)

Adviser: Yvonne T. Sanguinetti

Associated Adviser: Mário A. Hünicken

Abstract

This dissertation includes the study of 30 samples of two outcrops: Huaco and Loma de Los Piojos (Depto. Jáchal, Provincia de San Juan), belonging to San Juan Formation, Early Ordovician, Precordillera, Argentina. 17 genera and 28 species have been found in the processed samples. 17 species are multielemental species. The remaining ones are described as "sensu formae".

No new genus or species have been registered.

The conodont fauna from Huaco (section Buenaventura Luna), comprising elements of the speciesBaltoniodus navis (Lindström), makes it possible to relate the top of the San Juan Formation, in this locality, to the lower part of the Upper Arenigian. On the other hand, the conodont fauna from Loma de los Piojos (section Cerrito Pan de Azucar), including elements of the species Oepikodus evae (Lindström), permits to assign the top of the San Juan Formation, in this locality, to the upper part to the Lower Arenigian.

The presence of those species reveals an unquestionable connection with Baltoscandinavian Region.

PALINOLOGIA DA FORMAÇÃO RIO BONITO NA ÁREA DE GRAVATAÍ­MORUNGAVA, RIO GRANDE DO SUL

PALYNOLOGY OF THE RIO BONITO FORMATION IN THE AREA OF GRAVATAÍ­MORUNGAVA, RIO GRANDE DO SUL

Maria Elice Dias Fabrício (1980)

Adviser: Marleni Marques Toigo

Abstract

The study of four boreholes (5CA­80­RS, 5CA­99­RS, 5CA­91­RS, 5CA­98­RS) from Gravataí­Morungava coalfield, Rio Grande do Sul, Southern Brazil, reveals a palynological association of 45 genera and 74 species of spores and pollen grains.

The frequency of the main morphographic groups and the classification of the species of each borehole are presented.

Besides the systematic descriptions, the paleobotanical affinities andthe range of each species are also given. It is made an attempt to reconstruct the palaeoenvironment.

A great deal of the studied specimens are related to previously described types. A new genus and species (Elosporites conjugatus), four new species (Cristatisporites morungavensis, Cristatisporites solaris, Cristatisporites variornatus, Cristatisporites microvacuolatus) and four new combinations are proposed.

OSTEOLOGIA DO SINCRÂNIO DAS ESPÉCIES DE MENTICIRRHUS GILL, 1861 DA COSTA SUL DO BRASIL (PERCIFORMES, SCIAENIDAE)

SYNCRANIAL OSTEOLOGY OF THE SPECIES OF MENTICIRRHUS GILL, 1861 FROM THE SOUTHERN COAST OF BRAZIL (PERCIFORMES, SCIAENIDAE)

Leda Francisca Armani Jardim (1980)

Adviser: Mario C. Barberena

Abstract

The present dissertation deals with the osteology of the cranium of two species of the genus Menticirrhus GILL, 1861 found in Southern Brazil. It is based on the detailed observation of eight specimens belonging to M. littoralis and ten to M. americanus.

The material was fixed, preserved and subsequently disarticulated and submited to the usual processes for whitening, digestion and staining.

From the osteologic point of view, diagnostic differences are not outstanding since the species are very much alike. But these differences do offer good parameters for taxonomic separation. Some of these differences are the following: the lacrimal bone that shows a reasonably complex morfology offers distinctive features in the two species of Menticirrhus, as it is discussed in the text. The long, narrow nasal with the furrow of the lateral line more closed in M. littoralis, allows another point of differentiation from M. americanus, whose bone has distinct features.

The premaxillary dentition in both species is also distinct in form, number and distribution of villiform and comical teeth. The suture area between frontal and supraoccipital is elevated in M. littoralis, but not in the other species.

The crenulations of the preopercular and topography of the frontal is distinct in both species.

The "lower pharyngeals" teeth of the fifth ceratobranquial, which is wider in M. littoralis, are usually molariform; in M. americanus we can see predominantly developed conical teeth, indicating a higher predatoriness in this species.

Some significant osteologic differences are also found in the pharyngobranchials, branchial arches and in the neurocranium of both species.

Conspicuous differences in the external morphology are also present, but restricted to the kind of teeth of the premaxillary, a lower and longer head in M. littoralis and breast scales distinctly smaller than those of the rest of the body, which do not occur in M. americanus.

Finally, M. littoralis presents back and sides in silvery grey color, a white toned belly and generally clear fins.

M. americanus shows back and sides in a darker grey with five or six dark colored oblique strips, a white colored belly and generaly dark fins.

ESTUDO PALINOLÓGICO DA FORMAÇÃO PALERMO, ESTADO DE SANTA CATARINA, PERMIANO, BACIA DO PARANÁ, BRASIL

PALYNOLOGICAL STUDY OF THE PALERMO FORMATION, SANTA CATARINA STATE, PERMIAN, PARANÁ BASIN, BRAZIL

Beatriz Leipnitz (1981)

Adviser: Marleni Marques Toigo

Abstract

A palynological study of the Palermo Formation (Santa Catarina, Brazil) based on boreholes 1­AR­46­SC, 1­CR­13­SC­01 and 1­LM­102­SC has shown the presence of a microfloristic assemblage composed of 35 genera and 63 species. Two new species are described: Thymospora palermensis n.sp. and Thymospora catarinensis n.sp. Palaeomicroplankton represented by the genera Mycrhystridium and Verychachium was detected.

The frequency of the main morphological groups as well as a description of the occurring species, their vertical distribution and botanical affinities are presented. Besides, a palaeoecological interpretation for the occurring microflora was attempted.

A Kungurian age was assigned to the Palermo Formation based on the comparison of the studied palynological assemblage with published material on similar Gondwana assemblages.

MADEIRAS GIMNOSPÉRMICAS DA FORMAÇÃO IRATI NO RIO GRANDE DO SUL - CONTRIBUIÇÃO AO ESTUDO ANATÔMICO E PALEOECOLÓGICO

GYMNOSPERMIC WOODS OF THE IRATI FORMATION IN RIO GRANDE DO SUL - A CONTRIBUTION TO THE ANATOMICAL AND PALAEOECOLOGICAL STUDY

Regina Helena Castello Costa (1981)

Adviser: Margot Guerra­Sommer

Abstract

The anatomic, systematic, palaeoecological, and chemical composition aspects of fossil woods from Irati Formation, São Gabriel region, Rio Grande do Sul State, have been studied.

Polysolenoxylon bortoluzzii GUERRA, 1975, corresponds to the most frequent morphogenus in the Irati Formation, thus characterizing a biostratigraphic stage unconventionally called "Polysolenoxylon Zone" Rosler (1978); secretory cannals in the pith, associated with a secondary xilem of "mixed" type (Australoxylon MARGUERIER, 1971) are characteristics of the woody plane aspects. Myelontordoxylon glandulífera n. sp. is related to the "Vertebrarian Complex" (sensu Mussa, 1978b), which includes an association of stemsand roots, connected to swamp environments. Aracnomedulloxylon gabrielensis n.g., n. sp. has new characteristics at generic and specific levels.

Fossilization is by permineralization (sensu Buurman, 1972). The structures of the plant tissues are mainly preserved by minerals of the silica group, with predominance of the microcrystaline quartz (calce-dony). The sílica content is very high (84% a 92%).

Based on these data, inferences about the Irati depositional environ-ments in the São Gabriel­Batovi region are made, which seem to indicate an environment of shallow, calm water, periodically inundated by saline water.

MAMÍFEROS FÓSSEIS DO CENOZÓICO DO ALTO JURUÁ - ACRE

CENOZOIC FOSSIL MAMMALS FROM ALTO JURUÁ - ACRE

Alceu Rancy (1981)

Adviser: Carlos de Paula Couto

Abstract

The present dissertation deals with the study of a collection of fossil remains of mammals from the region of the upper Juruá River, State of Acre, Brazil. It includes a synoptic consideration on the regional climatic conditions, geographic localization and local ways of communication.

A summarized report on the paleontological researches already presented by several authors on material proceeding from the same region is also considered here, together with a rather general view on the respective geology and physiography, on the basis of data published by several authors (see bibliographical references).

The aim of this dissertation is the systematic descriptive study of the fossil remains of mammals from the Cenozoic of Acre, which belong to the collection of the Universidade Federal do Acre, Rio Branco. Six orders, eleven families and fifteen genera were identified.

OSTEOLOGIA DO SINCRÂNIO E ODONTOLOGIA DE EUPHRACTUS SEXCINCTUS

SYNCRANIAL OSTEOLOGY AND ODONTOLOGY OF EUPHRACTUS SEXCINCTUS

Jorge Ferigolo (1981)

Adviser: Carlos de Paula Couto

Abstract

This dissertation deals with the description of the syncranium and the odontological study of Euphractus sexcinctus, a representative species of the most primitive group of the Order Edentata, the Dasypodidae.

The syncranium is described in general views and bone by bone. Nervous and vascular foramina, grooves and canals, and the nasal, sinusal and the independently cranic (properly said) cavities are also studied. The mandibular mechanics is analyzed based on the morphological features from the cranium, dentary and teeth.

A radiologic study of the syncranium of Euphractus sexcinctus and a comparative study between this species and Dasypus novemcinctus are also made.

The plesiomorphic and apomorphic characters are considered and discussed in view of the most recent knowledge concerning this order.

This group is considered to have had its origin and evolution in South America or at least in Gondwana.

ESTUDO MORFOLÓGICO E BIO­ESTRATIGRÁFICO DE ESCAMAS DA PALEOICTIOFAUNA DO GRUPO PASSA DOIS (PERMIANO), BRASIL

MORPHOLOGICAL AND BIOSTRATIGRAPHICAL STUDY OF SCALES FROM THE PALEOICTHYOFAUNA OF THE PASSA DOIS GROUP (PERMIAN), BRAZIL

Martha Richter (1981)

Adviser: Irajá Damiani Pinto

Abstract

In this dissertation ten morphological types of paleoniscid and one of coelacanthid scales are described. They come from outcrops and cores of the Irati Formation of Paraná and Rio Grande do Sul States and of the Estrada Nova Formation of the latter.

The classification of these exo­ ­skeletal elements is artificial, elaborated principally with strati-graphical purposes.

It is discussed the importance of fish scales to the ichthyological Taxonomy and to Geology.

A normative chapter about the criteria of describying scales is presented, together with a general glossary of terms refering to this study.

Some conclusions of strati-graphical character are introduced, supported by the morphological affinities and bio­stratonomy of the scales, allied to information derived from the geological literature.

OSTRACODES DA PLATAFORMA DE SAHUL, NW DA AUSTRÁLIA - FAMÍLIAS BAIRDIIDAE SARS, 1888 E CYTHERELLIDAE SARS, 1866

OSTRACODA FROM THE SAHUL SHELF, NW AUSTRALIA - FAMILIES BAIRDIIDAE SARS, 1888 AND CYTHERELLIDAE SARS, 1866

Maria Elizabeth Viñas Gomes da Silva (1981)

Adviser: Irajá Damiani Pinto

Abstract

The present dissertation deals with the systematic study of Recent Ostracoda species from Sahul Shelf, northwestern Australia, and gives some information on the distribution of these organisms in relation to bathymetric, lithologic and facies data.

The Families Bairdiidae Sars 1888 and Cytherellidae Sars 1866 were studied; a new genus and 14 new species were described.

UMA NOVA ESPÉCIE DE TECODONTE AETOSSAURIO, AETOSAUROIDES SUBSULCATUS SP.NOV., DA FORMAÇÃO SANTA MARIA, TRIÁSSICO DO RIO GRANDE DO SUL, BRASIL

A NEW SPECIES OF AETOSAURIAN THECODONT, AETOSAUROIDES SUBSULCATUS N.SP., OF THE SANTA MARIA FORMATION, TRIASSIC FROM RIO GRANDE DO SUL, BRAZIL

Jussara Dorneles Zacarias (1982)

Adviser: Mario C. Barberena

Abstract

This dissertation deals with the taxonomy and osteological description of a new aetosaurian thecodont, Aetosauroides subsulcatus, n.sp., from the upper levels of the Santa Maria Formation (Triassic of Rio Grande do Sul State, Brazil). The main specific differences from A. scagliai (Ischigualasto Formation, Triassic of Argetina) are related tothe surface ornamentation of the osteoderms which is more strongly developed in the Argentinian form. Biostratigraphically, the new species belongs to the Rhynchocephalia Assemblage­zone of the Santa Maria Formation and indicates a Lower Ischigualastian age for the upper beds of this formation.

SCAPHONYX SULCOGNATHUS (SP.NOV.), UM NOVO RINCOSSAURÍDEO DO NEOTRIÁSSICO DO RIO GRANDE DO SUL, BRASIL

SCAPHONYX SULCOGNATHUS (N.SP.), A NEW RHYNCHOSAURID FROM THE LATE TRIASSIC OF RIO GRANDE DO SUL, BRAZIL

Sérgio Alex K. de Azevedo (1982)

Adviser: Mario C. Barberena

Abstract

This study deals with the osteological description of the skull and lower jaw of Scaphonyx sulcognathus, n.sp., a new species of rhynchosaur from the Caturrita Formation, Upper Triassic of Rio Grande do Sul State, southern Brazil.

The new species presents clear morphologic differences from Scaphonyx fischeri SMITH WOODWARD 1907 (Santa Maria Formation, Middle to Upper Triassic of Rio Grande do Sul) and Scaphonyx sanjuanensis SILL 1970 (Ischigualasto Formation, Upper Triassic of Argentina). These differences are particularly seen in the mastigatory apparatus. Two sulci in the maxila and two corresponding ridges in the lower jaw of the new speciesclearly differenciate it from S. fischeri and S. sanjuanensis, which exhibits only one of these structures. Accordingly, variation in the number and arrangement of the teeth is detectable in the new species. Skull proportions are also different in Scaphonyx sulcognathus.

The dental characteristics suggest that its diet included softer elements in comparison to the hard seeds probably ingested by the other two species.

Scaphonyx sulcognathus occurs associated with Jachaleria, Exaeretodon and Proterochampsa in the Caturrita Formation. This paleofaunal assemblage suggests an Upper Ischigualastian to Coloradian age for these beds.

PALEONTOLOGIA, ESTRATIGRAFIA E BIOESTRATIGRAFIA DA FORMAÇÃO SANGA DO CABRAL (TRIÁSSICO INFERIOR DO GRUPO ROSÁRIO DO SUL), NA FOLHA DE CATUÇABA, RIO GRANDE DO SUL

PALEONTOLOGY, STRATIGRAPHY AND BIOSTRATIGRAPHY OF THE SANGA DO CABRAL FORMATION, EARLY TRIASSIC (ROSÁRIO DO SUL GROUP) IN THE CATUÇABA QUADRANGLE, RIO GRANDE DO SUL

Ernesto Luiz Lavina (1982)

Adviser: Mario C. Barberena

Abstract

This dissertation deals with the osteological description of procolophonid remains, associated with rhytidosteid amphibians. They occur in intraformational conglomerates of the Sanga do Cabral Formation (Rosário do Sul Group, Triassic), in the region of Catuçaba, Rio Grande do Sul State, Southern Brazil.

Though fragmentary, the remains allowed the identification of Procolophon sp., represented by cranial and postcranial materials.

The presence of Procolophon indicates an equivalent of the Lystrosaurus zone (Upper Beaufort Series of South Africa) for the basal sequence of the Rosário do Sul Group, and thus assigns to the Sanga do Cabral Formation a Scythian (Lower Triassic) age.

The occurrence of this paleofauna shows that the Permo­Triassic limit in Rio Grande do Sul, as interpreted by paleofaunal succession, should not register any major hiatus. In fact, the topmost levels of the Upper Permian, underlying the Estrada Nova Formation (Armada Facies), have displayed Pareiasaurus remains; this is in agreement with the paleofaunistic sucession between the Lower and Upper Beaufort Series in South Africa.

The area corresponding to the Catuçaba Quadrangle was mapped to the scale of 1:50000 in order to describe the stratigraphic, lithologic and sedimentary features of Sanga do Cabral Formation.

This formation is here interpreted as deposited under the influence of a fluvial meandering systems. Channel and flood plain deposits were recognized.

Intraformational conglomerates are interpreted as the reworking of upper point bar and flood plain pelitic sediments as currents during floods.

O GÊNERO PURIANA (OSTRACODA). OCORRÊNCIA NA PLATAFORMA CONTINENTAL BRASILEIRA, ECOLOGIA, DISTRIBUIÇÃO GEOGRÁFICA E ESTRATIGRÁFICA

THE GENUS PURIANA (OSTRACODA). ITS OCCURRENCE IN THE BRAZILIAN CONTINENTAL SHELF, ECOLOGY AND GEOGRAPHIC AND STRATIGRAPHIC DISTRIBUTION

Katia Chukewiski (1984)

Adviser: Ivone Purper

Abstract

The present dissertation deals with the genus Puriana (Ostracoda), showing its ecology, geographical and stratigraphical distribution. The study of this genus in the Brazilian Continental Shelf allowed the description of the new species - Puriana variabilis Chukewiski, 1984, and the registration of the occurrence of Puriana convoluta Teeter, 1975.

Based on the distribution of the genus Puriana and its association in the Caribbean region, it is suggested that the Caribbean faunule could have spread till the latitude 09°41,5'S in the Brazilian coast.

REVISÃO SISTEMÁTICA DE BIVALVES (MOLLUSCA) PROVENIENTES DE ESTRATOS DA FORMAÇÃO PONTA GROSSA - DEVONIANO - NO ESTADO DO PARANÁ

SYSTEMATIC REVISION OF BIVALVES (MOLLUSCA) FROM STRATA OF THE PONTA GROSSA FORMATION - DEVONIAN - PARANÁ STATE

Suzana Maria Morsch (1984)

Adviser: Ieda Regina Forti Esteves

Associated Adviser: Bruno A.J. Baldis

Abstract

A systematic revision of some bivalve species of the Devonian Ponta Grossa Formation (Paraná State, Brazil) is presented. These species were described or mentioned by Clarke in 1913. New specimens were used in some of the redescriptions. Lectotypes were selected among Clarke's syntypes deposited in the collection of the "Seção de Paleontologia" of the "Divisão de Geologia e Mineralogia" (DNPM), Rio de Janeiro.

Species belonging to the genus Nuculites were not revised, though forms similar to Nuculites pacatus, N. reedi and N. sharpei are mentioned. Mention is also made in reference to Solemya (Janeia) (?) cf. brasiliensis, Sphenotomorpha sp. and Sanguinolites sp.

The revision here proposed includes the following taxa: Palaeoneilo magnifica, P. sancti­crucis, P. (?) rhysa, Nuculana (?) viator, Solemya (Janeia) (?) brasiliensis nov. comb., Modiomorpha (?) austranotica, Modiomorpha (?) erebus nov. comb., Sphenotomorpha ulrichi nov. comb., Pleurodapis multicíncta, Cypricardella (?) olivieria, Cardiomorpha (?) colossea, Orthonota (?) bokkeveldensis nov. comb., Grammysioidea scaphula, Grammysioidea capricornus nov. comb., Pholadella (?) cf. radiata and Prothyris (Paraprothyris) knodi.

The taxonomic delimitation of Phthonia (?) epops, Goniophora (?) abreviata and Sanguinolites lagoensis nov. comb. is also discussed.

A SUBFAMÍLIA ORIONININAE PURI, 1973 NA PLATAFORMA CONTINENTAL BRASILEIRA

THE SUB­FAMILY ORIONININAE PURI, 1973 IN THE BRAZILIAN CONTINENTAL SHELF

João Carlos Coimbra (1984)

Adviser: Lilia Pinto de Ornellas

Abstract

This dissertation deals with the systematic, the bathymetrical and geographical distributions, associated to the ecological data, of the species of the subfamily Orionininae Puri, 1973 found at the Brazilian Continental Shelf.

In the systematic study made, two genera and seven species - four of which are new species - were identified.

Caudites nipeensis Van den Bold, 1946, Orionina bradyi Van den Bold, 1963 and Orionina similis Vanden Bold, 1963, were for the first time registered in the northern and eastern Brazilian Coast.

The study of the geographical and bathymetrical distributions, together with the analysis of the ecological data, led to the characterization of three different associations along the shelf. Between the northern/eastern and the southern associations a transitional zone, corresponding to the meridional part of the eastern shelf, was found.

UM NOVO SPHENOSUCHIA (BARBERENASUCHUS BRASILIENSIS GEN.ET SP.NOV.) DO MESOTRIÁSSICO DO RIO GRANDE DO SUL, BRASIL

A NEW SPHENOSUCHIA (BARBERENASUCHUS BRASILIENSIS, N.G., N.SP.) FROM THE MIDDLE TRIASSIC OF RIO GRANDE DO SUL, BRAZIL

Luiz Cláudio Borges Mattar (1985)

Adviser: Mario C. Barberena

Associated Adviser: Dina C. Fernandes Araújo

Abstract

The present dissertation deals with the osteological description of the skull and second cervical vertebra of Barberenasuchus brasiliensis (n.gen. and sp.), a new sphenosuchid thecodont from the Santa Maria Formation (Pinheiros Local Fauna), Triassic of Rio Grande do Sul State, southern Brazil.

Generic diagnostic differences are to be seen between the new form and other South American sphenosuchids, such as: a) a narrow and vertically elongated infratemporal opening; b) a forward inclination of the quadrate and quadratojugal, caused by a moderately shorter lower jaw; c) squamosal flange present, but not so much expanded as in other related forms (e.g. Pseudhesperosuchus); d) presence of pterygoid teeth.

The finding of B. brasiliensis in the Santa Maria Formation reinforcesthe chronocorrelation between the Pinheiros and Los Chañares Local Faunas, confirming the Early Chanarian age already attributed to these paleoherpetofaunas.

The possible origin of the Crocodylia in Middle Triassic sphenosuchid thecodonts is also commented. It is concluded that the paucity of cranial material in Lewisuchus and the almost complete lack of postcranial elements in Barberenasuchus do not offer any sound evidence to clarify this question.

On the other hand, Barberenasuchus and Pseudhesperosuchus share several characters. The more primitive state of some of them in the Brazilian form seems to indicate it as an adequate ancestral to the Argentinian one.

PALINOLOGIA DOS TESTEMUNHOS DE SONDAGEM 2­TG­69­RS E 2­TG­99­RS DA JAZIDA CARBONÍFERA DE SANTA TEREZINHA, RS, BRASIL - PERMIANO DA BACIA DO PARANÁ

PALYNOLOGY OF BOREHOLES 2­TG­69­RS AND 2­TG­99­RS FROM THE SANTA TEREZINHA COAL FIELD, RS, BRAZIL - PERMIAN OF PARANÁ BASIN

André Tonetto Picarelli (1986)

Adviser: Ivone Purper

Associated Adviser: Marleni Marques Toigo

Abstract

Sporo­pollinic assemblages from two boreholes of Santa Terezinha Coal Field, Rio Grande do Sul State, Brazil, were described in this paper. The sedimentary sequence includes four lithostratigraphic units: Itararé Group indivisible, Guatá Group (Rio Bonito and Palermo Formations) and Passa Dois Group (Irati Formation). The palynological content is marked by trilete and monolete spores, related to PTERYDOPHYTA, pollen grains (Monosaccites, Disaccites and Striatiti) related to GYMNOSPERMAE, ALGAE (Botryococcus braunii) and Microplankton (Acritarchas - Sub-group Acanthomorphitae). Through quantitative and qualitative analyses as well as the study of botanical affinities, two palaecologic intervals were defined: Interval A,corresponding to the maximum occurrence of spores, reflecting a vegetation from an higrofilous environment related to the bogs and to the lacustrine­paludal sedimentat-ion of the Rio Bonito Formation; Interval B, related to the transgression which has driven the sedimentation of Palermo and Irati Formation, that is marked by an increase of pollen grains related to a mesophilous­xerophilous vegetation. At the middle part of Interval B, an acritarch­bearing horizon was identified, which points out the highest level of the transgression in the studied area. For the Interval A and for the first half of Interval B, it was determined a Lower Permian age. For the second half of Interval B, an Upper Permian age was determined.

SANTOSICHTHYS MAFRENSIS GEN.ET SP.NOV., UM NOVO PALEONISCIFORME DO PERMIANO INFERIOR DE SANTA CATARINA, BRASIL

SANTOSICHTHYS MAFRENSIS N.G., N.SP., A NEW PALAEONISCIFORM FROM THE LOWER PERMIAN OF SANTA CATARINA, BRAZIL

Maria Cláudia de S. L. Malabarba (1986)

Adviser: Mario C. Barberena

Associated Adviser: Martha Richter

Abstract

This dissertation deals with the description of a new genus and species of fossil fish: Santosichthys mafrensis (Elonichthyidae, PALAEONISCIFORMES).

The fossil fish is represented by a single specimen preserved as a skull and trunk cast in a silica concretion coming from shales of Rio do Sul Formation, Lower Permian of Santa Catarina State, Brazil.

Main differences between the new form and other Elonichthyidae are seen mainly in the morphology of cranial bones.

Allied to the description, some taxonomic and biostratigraphic comparisons with related palaeoichthyofaunes are brought into consideration.

DESCRIÇÃO DO SINCRÂNIO DE EREMOTHERIUM LAURILLARDI LUND, 1842. TAXONOMIA E PALEOBIOGEOGRAFIA

DESCRIPTION OF THE SYNCRANIUM OF EREMOTHERIUM LAURILLARDI LUND, 1842. TAXONOMY AND PALEOBIOGEOGRAPHY

Peter Mann de Toledo (1986)

Adviser: Mario C. Barberena

Associated Adviser: Jorge Ferigolo

Abstract

The present dissertation deals with the osteological description of the syncranium of Eremotherium laurillardi (Lund, 1842), a megatheriid of late Pleistocene to early Holocene from the State of Rio Grande do Sul, Brazil.

The specimen shows characteristics similar to E. laurillardi and to E. rusconii. It is proposed here that Eremotherium is monospecific, being the species name E. laurillardi (Lund, 1842).

The most meridional occurrence of Eremotherium is registered, and it implies the need to carry out more accurate studies about the palaeobiogeography of this group, and of Megatherium as well. This new occurrence calls our attention to the necessity of a taxonomic review of the material ascribed to the Pleistocene megatheres in the Southern Region of Brazil and Northern of Argentina and Uruguay.

OSTEOLOGIA PARCIAL DO PÓS­CRÂNIO DE SCAPHONYX SULCOGNATHUS AZEVEDO 1982 (LEPIDOSAURIA, RHYNCOCEPHALIA, RHYNCHOSAURIDAE)

PARTIAL OSTEOLOGY OF THE POST­CRANIUM OF SCAPHONYX SULCOGNATHUS AZEVEDO 1982 (LEPIDOSAURIA, RHYNCOCEPHALIA, RHYNCHOSAURIDAE)

César Leandro Schultz (1986)

Adviser: Mario C. Barberena

Associated Advisers: Dina C. Araújo-Barberena e

Sérgio A.K. de Azevedo

Abstract

This dissertation deals with the partial postcranial osteology of Scaphonyx sulcognathus Azevedo 1982, a rhynchosaur of the Brazilian Upper Triassic (Caturrita Formation, Rio Grande do Sul State).

Several features, supporting the already stated diagnostic characters for the skull, are to be seen in postcranial elements such as cervical vertebrae, scapular girdle and humerus.

S. sulcognathus had a light bony structure. Its limbs were more closer to the sagital plan than in other rhynchosaurids, revealing its more advanced evolutionary degree.

The species belongs to the Botucaraí Local Fauna, integrating an advanced paleoherpetofauna of thecodonts, cynodonts and dicynodonts, also found in the upper levels of the Argentinian Triassic. This indicates a Neoischigualastian to Eocoloradian (Norian) age for the sediments where S. sulcognathus is found (Caturrita Formation). The stratigraphic position of the Caturrita Formation, at the top levels of the Triassic sequence in southern Brazil, reinforces this geochronological evidence.

ARCHAEOGASTROPODA (SUPERFAMÍLIAS PLEUROTOMARIACEA SWAINSON, 1840 E FISSURELLACEA FLEMING, 1822) DA PLATAFORMA CONTINENTAL BRASILEIRA

ARCHAEOGASTROPODA (SUPER­FAMILIES PLEUROTOMARIACEA SWAINSON, 1840 AND FISSURELLACEA FLEMING, 1822) FROM THE BRAZILIAN CONTINENTAL SHELF

Angélica Stobäus Mattar (1986)

Adviser: Ieda Regina Forti Esteves

Abstract

In this dissertation archaeogastropods of the Superfamilies Pleurotomariacea Swainson, 1840 and Fissurellacea Fleming, 1822 are studied. They were collected during the REMAC Project, along the Brazilian Continental Shelf, from Amapá to Rio Grande do Sul.

Twelve species were identified: Scissurella (Anatoma) aedonia Watson, 1886; Emarginula phrixodes Dall, 1927; Emarginula pumila (A. Adams, 1851); Emarginula luberculosa Libassi, 1859; Puncturella (Cranopsis) granulata (Seguenza, 1863); Diodora dysoni (Reeve, 1850); Diodora fluviana (Dall, 1889); Diodora jaumei Aguayo & Rehder, 1936; Diodora meta (Ihering, 1927); Diodora mirifica Métivier, 1972; Diodora sayi (Dall, 1889) and Lucapinella limatula (Reeve, 1850). The species Puncturella (Cranopsis) billsae Farfante, 1947 is described for the first time for the Brazilian coast, and Sinezona brasiliensis is described as a new species. Scissurella (Anatoma) aedonia, Emarginula pumila, Puncturella (Cranopsis) granulata, Diodora dysoni, D. fluviana, D. jaumei and D. mirifica have their geographic distribution amplified along the Brazilian coast.

Five of them, Scissurella (Anatoma) aedonia, Emarginula pumila, Puncturella (Cranopsis) granulata, Diodora dysoni and D. mirifica have their bathymetric distribution amplified too.

For the fourteen archaeogastropod species observed, only Puncturella (Cranopsis) granulata, Diodora fluviana and D. mirifica showed agreement in the relation species/substrate.

From all determined species, only Scissurella (Anatoma) aedonia, Puncturella (Cranopsis) billsae, Puncturella (Cranopsis) granulata and Lucapinella limatula were considered eurythermal, belonging to both Caribean and Argentinian Provinces. The others occurred in areas considered as Caribean Province.

The studied species, in their majority, are registered only for the Recent.

CAIMAN BREVIROSTRIS SP.NOV., DO PLEISTOCENO DO ACRE, BRASIL

CAIMAN BREVIROSTRIS N.SP., FROM THE PLEISTOCENE OF ACRE, BRAZIL

Jonas Pereira de Souza Filho (1986)

Adviser: Mario C. Barberena

Associated Adviser: Ernesto Luiz Correa Lavina

Abstract

The present dissertation deals with the osteologic description of fragmentary, though taxonomically diagnostic, materials (partial skull and jaw ramus) of Caiman brevirostris n.sp., an aligatorid crocodile of the Solimões Formation (Pleistocene of Acre State, Brazil).

It also deals with the taxonomical interpretation and comparisons of the new species with related forms in South America.

Diagnostic differences in relation to other crocodilians are: a) Skull proportionally short and wider; b) maxilla entering ventrally between the pre­maxillae, until the level of the 5º maxillany tooth; c) the premaxillary­maxillary suture does not cut the fossa for the 4º mandibular tooth; d) orbits proportionally larger.

The morphologic characteristics of C. brevirostris do not show marked adaptation, to the point of suggesting a quite different habitus, in relation to the Caiman living species.

A brief review of the evolution of the crocodilian Suborders is also presented. Comments on the occurrence of giant crocodiles, in the Brazilian Amazonian area, area made.

O GÊNERO ACTINOCYTHEREIS (OSTRACODA) NA PLATAFORMA CONTINENTAL BRASILEIRA - TAXONOMIA, DISTRIBUIÇÕES GEOGRÁFICA E BATIMÉTRICA E RELAÇÕES ECOLÓGICAS

THE GENUS ACTINOCYTHEREIS (OSTRACODA) IN THE BRAZILIAN CONTINENTAL SHELF - TAXONOMY, GEOGRAPHIC AND BATHYMETRIC DISTRIBUTIONS, ECOLOGICAL RELATIONSHIPS

Maria Inês Freitas dos Santos (1987)

Adviser: Lilia Pinto de Ornellas

Abstract

This study is a survey on the presence of the genus Actinocythereis Puri 1953 (TRACHYLIBARIDAE) in the Brazilian Continental Shelf.

The obtained data revealed the presence of a single species of the genus, Actinocythereis saccharis n. sp., herein described.

The limits of its geographic (between 16°49' and 35°06' ofsouthern latitude) and bathymetric (from 22 to 164m) distributions were determined; species belonging to other genera and found in association with A. saccharis were identified.

An account on the ecology, and the stratigraphic and geographic distributions of the species of the genus Actinocythereis throughout the world is also presented.

RADIOLÁRIOS POLYCYSTINA (FAMÍLIA COLLOSPHAERIDAE) EM SEDIMENTOS PLEISTO­HOLOCÊNICOS DA MARGEM CONTINENTAL SUL­BRASILEIRA. SISTEMÁTICA. CONSIDERAÇÕES GERAIS SOBRE ECOLOGIA, PALEOECOLOGIA, DISTRIBUIÇÃO GEOGRÁFICA E GEOLÓGICA

POLYCYSTINA RADIOLARIANS (COLLOSPHAERIDAE FAMILY) IN PLEISTOCENE/HOLOCENE SEDIMENTS FROM THE SOUTHERN BRAZILIAN CONTINENTAL MARGIN. SYSTEMATICS. GENERAL CONSIDERATIONS ON ECOLOGY, PALAEOECOLOGY AND GEOGRAPHIC AND GEOLOGIC DISTRIBUTIONS

Valesca Maria Portilla Eilert (1988)

Adviser: Ieda Regina Forti Esteves

Associated Adviser: Sônia Conceição Bender Kotzian

Abstract

This study deals with the family Collosphaeridae (Polycystina, Spumellaria), which comprises the species of colonial radiolarians bearing simple siliceous shells. The main purpose of this dissertation is the systematic study of the group. In addition, other relevant topics were studied, resulting in a synthesis of the current knowledge of the collosphaeridae, including aspects of their biology, ecology, geographical and geological distribution.

The results of this research add new data to the more ample study of the Subclass Radiolaria, which has been developed throughout this decade in the sector of Micro-paleontology of this University.

The analyzed material, represented exclusively by isolated shells, was obtained in 4 samples of superficial sediments and 13 cores from the South Brazilian Continental Margin.

Different methods of sample preparation have been tested (4 altogether), with the aim of improving current procedures. Is was verified that the radiolarian groups presented different reactions to each technique. The more fragile forms, which include collosphaerids, are best preserved by using the more simplified methodology.

From the 6 genera presently related to the family Collosphaeridae, 4 have been found in these sediments: Acrosphaera Haeckel, 1881; Collosphaera Müller, 1885; Siphonosphaera Müller, 1858 e Trisolenia Ehrenberg, 1860a. Individuals of the genus Acrosphaera were the most frequent and abundant, followed by Collosphaera. Siphonosphaera and Trisolenia are very rare, specially the latter, from which only 5 individuals were found.

The following taxa were identified: Acrosphaera lappacea (Haeckel, 1887); Acrosphaera monodon (Haeckel, 1887); Acrosphaera spinosa (Haeckel, 1862); Collosphaera huxleyi Müllr, 1855 (presenting 2 distinct morphotypes: Collosphaera huxleyi (forma huxleyi) and Collosphaera huxleyi (forma tuberosa)); Collosphaera macropora Popofsky, 1917; Siphonosphaera polysiphonia Haeckel, 1887; Siphonosphaera tenera Brandt, 1885; Gen. et sp. indet. A; Trisolenia megalactis Ehrenberg, 1860a and Trisolenia tenuissima (Hilmers, 1906).

The species A. monodon, S. tenera, and T. tenuissima were found for the first time in the South Atlantic, having not been previously registered in this oceanic sector either for sediment or plankton. Furthermore, this is also the first worldwide register of T. tenuissima in sediment samples, since this species had only been found in the plankton of the Pacific and North Atlantic (Sargasso Sea).

Since colonial radiolarians are good indicators of warm superficial waters, an attempt was made to determine possible temperature changes during the Late Pleistocene­Holocene in the sediments of core T 15. This preliminary investigation was based on the comparison between warm water assemblages, in this case represented by the collosphaerids, and a cold water assemblage, cited by Eilert (1985). It was found out that, in certain intervals, the behaviour of the assemblages was significant, in the same way as the results obtained in Palynology by Lorscheitter & Romero (1985) for the same core. The predominance of warm water species within the interval of 4.60m to 5.80m (with slight oscillations) coincides with section II, related to the Interstadial Würm by the already mentioned authors.

Throughout the development of this study it was noticed that there are gaps concerning a great deal of information and data, which would certainly be of complementary value. Thus, it was considered as appropriate to include suggestions of studies that might be carried out in the future, aiming at the improvement of the knowledge about this group of microorganisms in the South Atlantic, from the bioecological as well as paleontological and biostratigraphical point of view.

PALEOICNOLOGIA DOS SEDIMENTITOS BASAIS DA FORMAÇÃO RIO DO RASTO NO ESTADO DO RIO GRANDE DO SUL

PALEOICHNOLOGY OF THE BASAL SEDIMENTS OF RIO DO RASTO FORMATION IN RIO GRANDE DO SUL STATE

Renata Guimarães Netto (1988)

Adviser: Dina Celeste Araújo­Barberena

Abstract

This dissertation presents an analysis of the ichonofauna occurring at Serrinha Member, Rio do Rasto Formation, Rio Grande do Sul State, Brazil. The ichnofossils belong to the Cruziana ichnofacies, which includes the ichnogenera Coclichnus Helminthopsis, Isopodichnus, ?Oldhamia, Planolites, Teicichnus, Thalassinoides e Unarites. This assemblage is shared by two ichnocoenosis, A and B,characterizing high and low energy, respectively. With the other sedimentary structures they suggest a deposition on subtidal and intertidal facies. The A ichnocoenose, which is rich in traces with protrusive spreiten, reveals a quick and continuous sedimentation, in contradistinction to B ichnocoenose, whose grazing traces show slow sedimentation.

O GÊNERO UROCYTHEREIS RUGGIERI, 1950 (OSTRACODA) NA PLATAFORMA CONTINENTAL BRASILEIRA

THE GENUS UROCYTHEREIS RUGGIERI, 1950 (OSTRACODA) IN THE BRAZILIAN CONTINENTAL SHELF

Inês Azevedo (1988)

Adviser: Lilia Pinto de Ornellas

Abstract

This dissertation presents the systematic study, with the bathymetric and geographic distribution, of the species of the genus Urocythereis Ruggieri, 1950, on the Brazilian Continental Shelf. These data allowed to identify six new species: Urocythereis vicinicostata n. sp., U. alatus n. sp., U. biformis n. sp., U. sculpturis n. sp., U. muralis n. sp., U. tenuis n. sp. and an indeterminate one.

These species occur in the Brazilian Coast from the meridional boundary of the Rio Grande do Sul State until the south of Bahia State, forming a characteristic group of the Southern Shelf, although U. alatus, U. biformis, U. muralis and Urocythereis sp. exceed this boundary, reaching a region where Coimbra (1984) established the Zone of Fauna Transition, South­Eastern Shelf.

PALEONTOLOGIA DOS LINGULIDA (BRACHIOPODA, INARTICULATA) DA FORMAÇÃO PONTA GROSSA, DEVONIANO DA BACIA DO PARANÁ, BRASIL

PALEONTOLOGY OF THE LINGULIDA (BRACHIOPODA, INARTICULATA) FROM THE PONTA GROSSA FORMATION, DEVONIAN OF THE PARANÁ BASIN

Élvio Pinto Bosetti (1989)

Adviser: Ivone Purper

Abstract

The exposures of the Devonian sequence in the eastern­central region of Paraná State are composed of the Furnas and Ponta Grossa Formations. Regional unconformities mark the bottom and top of this sequence. Thirty outcrops within the area were prospected; it was found that the fossiliferous levels belong to the Ponta Grossa Formation.

The fossil fauna is composed of brachiopods, echinoderms, coelenterates, anellids, pelecypods, gastropods, cricoconarids, ostracodes, calyptoptomatids and fossil traces, with predominance of brachiopods.

The lingulids mentioned by Clarke (1913), as well as some new forms, were the subject of a systematic revision, leading to the adoption of new taxonomic interpretations, as follow: Lingula sagittalis n. sp., Lingula sagittalis var. quadrata n. sp., Lingula liliata n. sp., Lingula (?) sp. A, Morphotype A, Morphotypes B1, B2, B3, B4, Morphotypes C1, C2, C3, C4 and Morphotype D.

Systematic criteria utilized in reference to the fossil lingulids are discussed; Lingula paleocommunities present in the studied area are characterized.

FORAMINÍFEROS DA PLATAFORMA EXTERNA E TALUDE SUPERIOR DO ESTADO DE SANTA CATARINA: ANÁLISES QUALITATIVA E QUANTITATIVA

OUTER SHELF AND UPPER SLOPE FORAMINIFERA OF SANTA CATARINA: QUALITATIVE AND QUANTITATIVE ANALYSES

Laura Maria Corbellini (1989)

Adviser: Yvonne T. Sanguinetti

Associated Adviser: Alwine Bertels

Abstract

The benthonic and planktonic foraminiferal associations included in 8 superficial bottom sediment samples of the outer shelf and upper slope from the continental margin of Santa Catarina State, Brazil (GEOMAR XIV), were analyzed.

The species diversity (Fisher Ó and Shannon­Wiener indices) was calculated as well as the planktonic/benthonic ratio, the proportion of Textulariina, Miliolina and Rotaliina, the frequence, the dominance, and the constancy.

These parameters allowed to propose an ecological model for this region, defined as follows: samples located in the outer shelf (100m deep) show lower Ó values, higher proportion of Rotaliina, values of Shannon­Wiener index under 3, and higher benthonic proportion. On the other hand, the upper slope samples present higher Ó values, slightly higher proportion of Miliolina and Textulariina, the Shannon­Wiener index over 3, and also an increase in the planktonic proportion. 217 species grouped in 81 genera and 11 superfamilies were identified of which 194 belong to the benthonic and 23 to the planktonic fauna.

In the first group the following species occur more frequently: Angulogerina jamaicensis, Cassidulina bradshawi, Bulimina marginata, Buliminella elegantissima, Planulina foveolata, Uvigerina auberiana, Textularia pseudogramen, Globocassidulina subglobosa, Gyroidina parva, Bolivina ordinaria, Bolivina albatrossi, Cibicidoides aff. C. pseudoungerianus, Cassidulina curvata, Bolivina fragilis, Uvigerina peregrina parvula, Hanzawaia bertheloti, Cassidulina norcrossi australis, Uvigerina peregrina and Discorbis advenus.

The most frequent planktonic species are: Globigerinoides ruber s.l., Globigerina bulloides, Globorotalia scitula, G. tumida, G. crassaformis, G. truncatulinoides and Globigerinita glutinata.

SISTEMÁTICA E BIOESTRATIGRAFIA DOS NANOFÓSSEIS CALCÁRIOS DO NEOGENO E QUATERNÁRIO (PLEISTOCENO INFERIOR) DA ÁREA CENTRAL DA BACIA DE SANTOS

SYSTEMATICS AND BIOSTRATIGRAPHY OF THE NEOGENE AND QUATERNARY (LOWER PLEISTOCENE) CALCAREOUS NANNOFOSSILS FROM THE CENTRAL AREA OF SANTOS BASIN

Helena Maria Souto Gonçalves (1989)

Adviser: Lília Pinto de Ornellas

Abstract

This dissertation deals with the systematics of calcareous nannofossils of the Santos Basin central area and the achievement of a biostratigraphic zonation through the analysis of four holes: 1­SPS­5, 1­SPS­8, 1­SPS­10 and 1­SPS­14A comprising the Neogene and Quaternary (Lower Pleistocene).

By means of the systematic study it was established the occurrence of twenty five genera, seventy two species and one subspecies. The diagnosis emendation of nine genera, fifty one species and one subspecies was proposed.

The biostratigraphic study of the area allowed the recognition of four biostratigraphic zones (Zone Sphenolithus belemnos, Zone Helicosphaera ampliaperta, Zone Sphenoli-thus heteromorphus and Zone Discoaster brouweri) used by PETROBRÁS in the zonation of the Brazilian Continental Shelf, from Miocene to Pleistocene. This study also allowed the recognition and the amendment proposal for the definition of three biostratigraphic zones (Zone Triquetrorhabdulus carinatus, Zone Discoaster hamatus and Zone Discoaster quinqueramus) and a new validation proposal for the definition of the Zone Reticulofenestra pseudoumbilica. It was made the recognition and proposition of three biostratigraphic zones (Zone Discoaster kugleri, Zone Amaurolithus tricorniculatus and Zone Pseudoemiliania lacunosa) and the recognition and proposition of one superzone (Superzone Gephyrocapsa spp.) and twenty two subzones for the area.

ICTIÓLITOS DA FORMAÇÃO PEBAS - PERU

ICHTHYOLITHS OF PEBAS FORMATION - PERU

Nelson Augusto Flores Machado (1989)

Adviser: Irajá Damiani Pinto

Abstract

This dissertation briefly reviews the present status of knowledge on ichthyoliths, in terms of their importance, utilization and classificatory systems.

Existing classifications are unified, for the sake of uniformity, and the resultant classification is appliedto the Pebas Formation ichthyoliths in the Peruvian territory.

The Numerical Taxonomy system was used for ordaining the groupings inside the morphotypes; a preliminary catalogue of the up to now registered forms of this geologic formation was established.

BIOESTRATIGRAFIA DOS NANOFÓSSEIS CALCÁRIOS DA SUB­BACIA DE MUNDAÚ (BACIA DO CEARÁ)

BIOSTRATIGRAPHY OF CALCAREOUS NANNOFOSSILS FROM THE MUNDAÚ SUB­BASIN (CEARÁ BASIN)

Armando A. Scarparo Cunha (1990)

Adviser: Lília Pinto de Ornellas

Abstract

A biostratigraphic scheme is proposed for the Albian/Early Miocene interval (Ubanara Formation) of the Mundaú Sub­Basin, Ceará Basin, based on the nannofossil content of 20 exploratory wells drilled by PETROBRÁS. The biostratigraphic framework consists of 23 interval biozones defined by sucessive extinction levels of single index taxa.

The correlation of the analyzed wells allowed the construction of eight biostratigraphic sections thatinclude several hiatuses. The chief hiatuses are in the Turonian, Campanian, Lower Paleocene and Lower Eocene.

The observed data indicate the occurrence of at least ten erosive/ nondepositional events, four of which in the Cretaceous and six in the Tertiary.

The systematic revision in this work allowed the identification of 46 genera and 71 species.

MOLUSCOS QUATERNÁRIOS, GASTROPODA (ORDENS: MESOGASTROPODA, NEOGASTROPODA, HETEROGASTROPODA), DA MARGEM CONTINENTAL DO ESTADO DO AMAPÁ, BRASIL

QUATERNARY GASTROPODA MOLLUSKS (ORDERS: MESOGASTROPODA, NEOGASTROPODA, HETEROGASTROPODA), FROM THE CONTINENTAL MARGIN OF AMAPÁ STATE - BRAZIL

Nádia Teresinha Schröder­Pfeifer (1990)

Adviser: Ieda Regina Forti Esteves

Abstract

Gastropod mollusks Proso-branchia (Mesogastropoda, Neo-gastropoda and Heterogastropoda Orders) were studied in this dissertation, by examining 40 samples of bottom superficial sediments collected at the continental margin of Amapá State, Brazil (GEOMAR II).

Though mainly analized from a taxonomical point of view, the material also permitted to draw ecological, zoogeographical and stratigraphical considerations, thus contributing to a better knowledge of the Quaternary micro­faunistic associations of the Brazilian Atlantic coast.

Of the 58 identified species 33 belong to the Mesogastropoda order, 17 to the Neogastropoda and 8 to Heterogastropoda order.

As a first occurrence for Brazil, it was reported the genus and species Amphitalamus vallei Aguayo and Jaume, 1947, the subgenus Olivella (Minioliva) Olsson, 1956 and the species Vitrinella (Vitrinella) aff. floridana Pilsbry and McGinty, 1946, Macromphalina aff. palmatoris Pilsbry and McGinty, 1950, Cerithiopsis aff. cynthia Bartsch, 1911, Atlanta helicionoides Souleyet, 1852, Vanikoro aff. sulcata d'Orbigny, 1842, Opalia (Nodiscala) aff. aurifila (Dall, 1889).

Of the total of the identified species, 25 have been appointed as new register for the Amapá State.

Great part of the analyzed material is constituted of young forms, protoconch and embryos, suggesting autochthonous material. Most of these samples are worn out and/or broken, suggesting that they have been carried; thus they can be allochthonous.

It was noticed that some specimens of the studied species occurred at bathymetric limits yet unregistered in the previous bibliography.

Most of species were found in carbonate sand.

The oldest age account of the analyzed species dates from the Tertiary.

ESTUDO SISTEMÁTICO DOS NANOFÓSSEIS CALCÁRIOS DA BACIA DO ESPÍRITO SANTO (PALEOCENO­EOCENO)

SYSTEMATIC STUDY OF THE CALCAREOUS NANNOFOSSILS FROM THE ESPÍRITO SANTO BASIN (PALEOCENE­EOCENE)

Beatriz Appel Denhardt (1990)

Adviser: Lília Pinto de Ornellas

Abstract

The analysis of seven drillings by PETROBRÁS (Petróleo Brasileiro S.A.), 1­BI­1D­ES, 1­LS­1­ES, 1­BA­2­ES, 1­RBN­1­ES, 1­RBN­2­ ­ES, 1­PDI­1­ES and 4­LS­5­ES, on the emersed part of the Espírito Santo Basin, allowed the systematic study of Paleocene­Eocene calcareous nannofossils. Optic and scanning electronic microscopy was used for this study, emphasizing the technique and the preparation of samples for the scanning electron microscope.

The terms employed are the ones used by several authors, following the criteria and needs according to the type of microscope and updated according to the more recent and simplified studies.

Twenty eight genera and sixty one species were taxonomically recognized. Diagnosis amendments of five genera and fifty seven species are proposed.

Complementing and updating the Hay's systematics (1977), here used for most of the studied species, we included the following taxonomic units, not included in the classification proposed by that author: the Pyrmnesiales Christensen Order, 1962; the Noelaerhabdaceae Jerkovic Family, 1970; the Eu­discoasteraceae Prins Family, 1971; the Helicosphaeroidae Theodoridis Subfamily, 1984 and the Placozygus Hoffmann Genus, 1970; Neochiastozygus Perch­Nielsen Genus, 1971; Helicosphaera Kamptner Genus, 1954 emend. Theodoridis, 1984; Birkelundia Perch­Nielsen Genus, 1971; Calcidiscus Kamptner Genus, 1950; Helio­discoaster Tan Genus, 1927 emend. Theodoridis, 1984, subdivided into Helio­discoaster mohleri and Helio­discoaster binodosus Groups; and Tribrachiatus Shamrai Genus, 1963 emend. Romein, 1979.

A PRESENÇA DO GÊNERO ISCHIGUALASTIA COX, 1962 (REPTILIA, SYNAPSIDA, THERAPSIDA, ANOMODONTIA, DICYNODONTIA) NA FORMAÇÃO SANTA MARIA, RIO GRANDE DO SUL, BRASIL

THE PRESENCE OF THE GENUS ISCHIGUALASTIA COX, 1962 (REPTILIA, SYNAPSIDA, THERAPSIDA, ANOMODONTIA, DICYNODONTIA) IN THE SANTA MARIA FORMATION, RIO GRANDE DO SUL, BRAZIL

Cibele Schwanke Peruzzo (1990)

Adviser: Dina Celeste Araújo­Barberena

Abstract

This dissertation deals with the osteological description of an incomplete skull of a tuskless dicynodont from Santa Maria Formation, Rio Grande do Sul State.

The outcrop which contained this fossil belongs to the Pinheiros Local Fauna. Despite its incomplete state, it shows similarities with the Argentinian species Ischigualastia jenseni and owing to this fact it is here designated as Ischigualastia sp.

On the basis of the morphological characteristics of Ischigualastia sp., comparisons with the other known tuskless dicynodonts are made, which show that this new fossil has some features which enable us to consider it a rather advanced formwithin the dicynodont phylogeny. These advanced features point to an adaptation to the floral change occurred during the Permian/Triassic time.

The presenced of Ischigualastia sp. in the Santa Maria Formation increases the faunistic correlation between Brazil and Argentina during the Triassic. Besides, in Brazil, Ischigualastia occurs in a paleofauna considered older than the one in which the same genus occurs in Argentina. This suggests a faunal dispersion from East to West during the Triassic, an hypothesis also indicated by the correlation between other taxa as, for example, the rhynchosaurs.

BIOESTRATIGRAFIA DO TERCIÁRIO DA BACIA DE CAMPOS, COM BASE EM FORAMINÍFEROS PLANCTÔNICOS

TERTIARY BIOSTRATIGRAPHY OF THE CAMPOS BASIN, BASED ON PLANKTONIC FORAMINIFERA

Vitor dos Santos Abreu (1990)

Adviser: Ivone Purper

Abstract

Based on analyses of planktonic foraminifera of bore holes 1­RJS­20, 1­RJS­108, 4­RJS­249 and 1­RJS­305 in the Campos Basin, southeastern Brazilian continental margin, a biostratigraphic zonation for the Tertiary was proposed.

The local stratigraphic distribution of the taxa found was compared with their distribution elsewhere in the world (Bolli, 1957a,b,c; Blow, 1959 and 1969; Stainforth et alii, 1975; Bolli & Saunders, 1985).

In this zonation only interval zones were used, so that the upper limit of each zone is characterized by the extinction datum of its own index fossil.

Although fourteen zones were established for the Neogene, only eight zones were recognized for the Paleogene. This results from two non­depositional and/or erosive hiatuses identified in the studied area, which correspond to the basal Lower Paleocene and Upper Paleocene/basal Middle Eocene.

PALINOLOGIA DO NEOPALEOZÓICO DA BACIA DO PARANÁ NA REPÚBLICA ORIENTAL DO URUGUAY. CONSIDERAÇÕES BIOESTRATIGRÁFICAS E PALEOECOLÓGICAS

LATE PALEOZOIC PALYNOLOGY OF THE PARANÁ BASIN IN THE ORIENTAL REPUBLIC OF URUGUAY. BIOSTRATIGRAPHICAL AND PALAEOECOLOGICAL CONSIDERATIONS

Lourdes de Los Angeles Beri (1991)

Adviser: Marleni Marques­Toigo

Abstract

The palynological content of Neopalaeozoic rocks from the Paraná Basin in Uruguay is described.

Thirty­six genera and seventy species of sporomorphs were identified. The samples were collected from three boreholes, corresponding to the following lithostratigraphic units: San Gregorio, Tres Islas and Melo Formations.

Taking into account the vertical distribution and comparing it with data from other Gondwana regions, mainly from Brazil (Paraná Basin) and Argentina (Chaco­Paraná Basin), an informal stratigraphical division into two Intervals, named A and B, is proposed.

The Interval A, stratigraphically lower, presents dominance of spores over pollen grains, and among the latter, Monossacites are the best represented. The Interval B is located at an upper stratigraphical position and presents dominance of Striatiti.

An Artinskian/Kungurian age is attributed to Interval A and a Kazanian one to Interval B.

Since the marine palaeomicroplankton is lacking and there are present in the assembly some Incertae sedis fresh water forms, as Portalites gondwanensis, and also fresh or brackish water algae, as Botryococcus braunii, a continental palaeoenvironment, probably a lake or a lagoon, is proposed for the studied sediments.

ANATOMIA FUNCIONAL MASTIGATÓRIA DE SCAPHONYX SULCOGNATHUS

MASTIGATORY FUNCTIONAL ANATOMY OF SCAPHONYX SULCOGNATHUS

Richard Alfredo Fariña Tosar (1991)

Adviser: Mario C. Barberena

Abstract

This dissertation deals with the masticatory functional anatomy of Scaphonyx sulcognathus Azevedo & Schultz 1987 (Reptilia; Rhynchosauridae) from Caturrita Fm., Late Triassic of Rio Grande do Sul, Brazil.

The teeth morphology is described; a reconstruction of the adductor musculature and a model for jaw elevation are proposed.

A theoretical (i.e. historical, logical and prospective) chapter on Functional Anatomy is included.

The results are compared with the already known model for Scaphonyx fischeri Smith­Woodward 1907, and the ecological implications are discussed.

A palaeoecological niche of relatively less herbivorous specialization, different from the "nut­cracker" adaptation of related species, is proposed. Accordingly, a less extremely arid environment is inferred.

TAFONOMIA DA SEQÜÊNCIA TRIÁSSICA DO RIO GRANDE DO SUL: MORTE, TRANSPORTE, SOTERRAMENTO E DIAGÊNESE DA PALEOHERPETOFAUNA

TAPHONOMY OF THE TRIASSIC SEQUENCE OF RIO GRANDE DO SUL: DEATH, TRANSPORT, BURIAL AND DIAGENESIS OF THE PALEOHERPETOFAUNA

Michael Holz (1991)

Adviser: Mário C. Barberena

Abstract

The results of a research program, for the first time undertaken on the taphonomic aspects of the Middle and Late Triassic sequence of Rio Grande do Sul State (southern Brazil) are presented in this dissertation.

The study was based on 1096 fossil specimens, including from articulated skeletons to reworked and isolated bone fragments. Stratigraphical and sedimentological data were also used in order to establish a taphonomic model for the mentioned sequence. The diagenetic history and its influence on fossilization has been studied by petrographical analysis of 48 thin sections of bones and associated sedimentary rocks.

The fossil remains were classified in four major reptilian groups (dicynodonts, cynodonts, thecodonts and rhynchosaurs) which occur in three distinct levels of Local Faunas. The physical mode of preservation (articulated, disarticulated, broken etc.) and the spatial distribution were determined, so that the establishment of the following four taphonomic classes was allowed:

I - articulated skeletons;

II - articulated bones;

III - isolated bones;

IV - isolated and broken bones. These classes reflect both the increasing skeletal disorganization and the complexity of taphonomic history. The skeletons of Class I are originated by drifted and rapidly buried carcasses, which are produced by cyclic catastrophic flood events. At the other extremity, the broken elements from Class IV represent those bones not buried by the cyclic events but exposed over a long period, suffering weathering and reworking by factors like trampling and scavenger activity.

The study of selective transport (Voorhies Groups) of bone elements from dicynodonts and rhynchosaurs (the most representative groups of the Triassic herpetofauna) revealed that the hydraulic selection by current water was not important as a factor of disarticulation and scattering, although it occurred in some sites.

The computation of the fossil recuperation rate showed that, in a general way, the preservation is low and that there is a preservation bias against skulls (super­represented in the collection) and vertebrae (sub­represented).

The analysis of the size classes of the Triassic reptilian remains (taken as analogous to age classes) showed a distribution very similar to that exhibited by living communities, what indicates that small (= young), intermediate and huge (= old) individuals were buried together in a proportion which approximates the distribution pattern of a living population. This is taken as an evidence of catastrophic rather than attritional death.

Data from the author were integrated to other obtained from the literature, in order to draw a paleogeographical characterization of the southern Brazilian Triassic. This study permitted the elaboration of a regional climatic curve, and also revealed that the appearance of the different Local Faunas is correlated to important eustatic falls and coastal onlap migration registered for the global Triassic. This phenomenon is preliminary explained and commented on.

By bringing together all the stratigraphical, paleontological and taphonomical data, the modelation of the taphonomic history was made possible.

This model postulates a multi­ ­episodic history of catastrophic death and rapid burial of complete carcasses caused by periodic floods, which alternated with periods of exposure of bone elements and little or no burial.

The analysis of the diagenetical aspects pointed out that the main agents of fossilization are calcite (main component) and the iron oxides hematite and goethite (subordinate components). These minerals penetrate the vascular structure of the bones and the displacive nature of the calcite crystals breaks and expands the bone structure and modifies, sometimes almost completely, the macroscopic morphology and distinctive features.

PALINOLOGIA DE SEDIMENTOS DE UMA MATA TROPICAL PALUDOSA EM TERRA DE AREIA, PLANÍCIE COSTEIRA NORTE, RIO GRANDE DO SUL, BRASIL

PALYNOLOGY OF SEDIMENTS FROM A TROPICAL SWAMP FOREST IN TERRA DE AREIA, NORTHERN COASTAL PLAIN, RIO GRANDE DO SUL, BRAZIL

Paulo César Pereira das Neves (1991)

Adviser: Maria Luísa Lorscheitter

Abstract

A palynological study of sediments from a tropical swamp forest was carried out to obtain data on vegetational and climatic changes during the Upper Quaternary of the area. This forest is located in Terra de Areia, Northern Coastal Plain of Rio Grande do Sul, Brazil lat. 29°33'11"S; long. 50°03'03"W (core collection site), in a filled depression of an old Pleistocene beach ridge.

Quantitative and qualitative analyses were carried out on palynomorphs of 23 samples, collected from the bottom to the top of the chosen sedimentary core.

The qualitative analysis revealed 98 palynomorphs: fungi (13), algae (8), bryophytes (2), pteridophytes (12), gymnosperms (2), angiosperms (53), besides others not so representative.

In the quantitative analysis the palynomorphs found were studiedwith the goal of paleoclimatic interpretations. For this purpose the method used was the pollen concentration and percentual.

Additional analyses were performed on lithology, radiocarbon dating and floristic analysis of the present forest.

The results obtained showed meaningful vegetational and climatic changes starting at the last stage of the Pleistocene glaciation (23,800 ± 500 years B.P.), also at the limit Pleistocene­Holocene (± 11,000 years B.P.) besides minor amplitude oscillations occurred during the Holocene (4,120 ± 90 years B.P.).

The present paper reinforces the author's belief in the Actualism phylosophy in order to better understand the geological and biological phenomena acting during the Upper Quaternary in the Northern Coastal Plain of Rio Grande do Sul.

PALINOLOGIA DE SEDIMENTOS DA LAGOA DOS PATOS, RIO GRANDE DO SUL, BRASIL

PALYNOLOGY OF PATOS LAGOON SEDIMENTS, RIO GRANDE DO SUL, BRAZIL

Suzane Hilgert Cordeiro (1991)

Adviser: Maria Luisa Lorscheitter

Abstract

With the purpose of studying the vegetation and climatic changes in the last millennia of the Coastal Plain of Rio Grande do Sul, Brazil, a palynological study was made in the Northern part of the Patos Lagoon.

Twenty­four samples of one core of 2.26m at the depth of 7.70m (30°50'51" lat. S and 50°59'05" long. W) were collected. The samples underwent a chemical process and after that the palynomorphs found were submitted to qualitative and quantitative analyses. The quantitative analysis calculated the percentage and concentration of grains per gram of dry sediments. Also two radiocarbon datings were made at two different core levels.

The findings consisted of 7 Fungi, 3 Animal Remains, 2 Achritarcs, 11 Algae, 4 Bryophytes, 16 Pteridophytes, 3 Gymnosperms and 46 Angiosperms.

The palaeoenvironment analysis revealed a marine transgression into the lagoon in 5,170 +/- 120 years BP, giving rise to a local vegetation consisting chiefly of xerophytic and hallophytic elements. On the other hand, the vegetation of the humid environment characterized the most interiorized portions of the Coastal Plain at this time. These tendencies were increased at about 4,080 +/- 110 years BP, when the highest local level of marine transgression happened. This coincided with the beginning of the development of forest vegetation in the most interiorized portions of the Coastal Plain.

These data suggest that this marine transgression was a consequence of climatic changes to higher temperatures and more humidity at the global level.

After 4,000 years BP the sea gradually retreated giving to the Northern portion of the lagoon fresh water characteristics.

The development of forest vegetation beginning at 4,000 years BP, together with the absence of dry periods, reinforces the thesis of the influence of phenomena of El Niño­type throughout the latter millennia in South America.

O GÊNERO CALLISTOCYTHERE RUGGIERI, 1953 (OSTRACODA) NA PLATAFORMA CONTINENTAL BRASILEIRA

THE GENUS CALLISTOCYTHERE RUGGIERI, 1953 (OSTRACODA) IN THE BRAZILIAN CONTINENTAL SHELF

Vera Maria Bittencourt­Calcagno (1991)

Adviser: Lília Pinto de Ornellas

Abstract

This dissertation deals with the systematic, bathymetrical and geographical distributions of the species of the genus Callistocythere Ruggieri, 1953 found at the Brazilian Continental Shelf. In the systematic study made, five new species were identified: Callistocythere nodulosa, Callistocythere sigmocostelata, Callistocythere laminata, Callistocythere fossulata, Callistocythere cellaria, as well as two species already described: Callistocythere litoralensis (Rossi de Garcia, 1966) and Callistocythere cranekeyensis (Puri, 1960).

The occurrence area of the genus at the Brazilian coast goes from the meridional shore of the Rio Grande do Sul up to extreme limit ofAmapá State, overspreading to the South, East and North shelf. Data obtained through determination of the bathymetrical and geographical distributions of the genus allow to identify the area of each species. Callistocythere litoralensis (Rossi de Garcia, 1966) is restricted to the South shelf, Callistocythere nodulosa sp. nov., Callistocythere sigmocostelata sp. nov., Callistocythere laminata sp. nov., Callistocythere fossulata sp. nov., Callistocythere cellaria sp. nov. have an occurrence area which goes over the North/East shelf reaching the southern extremity of East shelf where the transition zone established by Coimbra (1984) is; Callistocythere cranekeyensis does not reach the transition zone.

ESTUDO TAXONÔMICO­POPULACIONAL DOS DICINODONTES COM PRESAS DO RS, MEDIANTE O EMPREGO DA ANÁLISE DISCRIMINANTE CANÔNICA (INDEPENDENTE DO TAMANHO)

TAXONOMIC­POPULATIONAL STUDY OF THE TUSK­BEARING DICYNODONTS OF RIO GRANDE DO SUL STATE, BY MEANS OF THE DISCRIMINANT CANONICAL ANALYSIS (SIZE­FREE)

Marcos Machado (1992)

Adviser: Dina Celeste Araújo­Barberena

Abstract

This thesis presents a taxonomic study on the tusk­bearing dicynodonts of Rio Grande do Sul State from a populational point of view. For this purpose, discriminant canonical analysis (size­free) was applied to a sample composed of 33 skulls. The specimens are included in the Pinheiros and Chiniquá Local Faunas, Santa Maria Formation, of Triassic age.

The above­mentioned populational approach enables to estimate the variability of the morphological characters in and among groups of specimens and also other aspects such as: 1) the analysis of the influence of the allometric growth over the shape; 2) the data obtained from the application of discriminant canonical analysis on the sample; 3) the assumed absence of discret osteological characters enabling a non­subjective diagnosis; and 4) the relationships between morphology and ecology.Based on these theoretical data, the taxonomy of the tusk­bearing dicynodonts is discussed.

Remarks upon the evolution of the nutritional habit in the dicynodonts were also made. In this evolutionary pattern, which was a complex phenomenon, a series of morphological (specially, in upper and lower jaws), biomechanical and physiological changes were involved, all of them related to an inferred progressive decrease in food availability. Besides, the fossil record and the paleoclimatic data show that dicynodonts dispersed from Africa towards South America along the Triassic, running away from the progressively arid environmental conditions. Thus, it is claimed that the climatic changes, the decrease of available food, and dispersion and changes in the nutritional habit are intrinsically related to the evolution of the dicynodonts in Triassic times.

CERRITOSAURUS BINSFELDI PRICE 1946 E CHANARESUCHUS SP. (THECODONTI, PROTEROSUCHIA, CERRITOSAURIDAE) DA FORMAÇÃO SANTA MARIA, TRIÁSSICO DO ESTADO DO RIO GRANDE DO SUL, BRASIL

CERRITOSAURUS BINSFELDI PRICE 1946 AND CHANARESUCHUS SP. (THECODONTIA, PROTEROSUCHIA, CERRITOSAURIDAE0 FROM THE SANTA MARIA FORMATION, TRIASSIC OF RIO GRANDE DO SUL STATE, BRAZIL

José Eduardo Figueiredo Dornelles (1992)

Adviser: Mario C. Barberena

Abstract

This dissertation deals mainly with the osteological revision of some cranial features of the type material of Cerritosaurus binsfeldi PRICE 1946, as well as with the description of Chanaresuchus sp. These cerritosaurid thecodonts were collected in sediments pertaining to the Santa Maria Formation (Middle to Late Triassic) in Rio Grande do Sul State, southern Brazil.

Careful evaluation of the taphonomic effects in Cerritosaurus binsfeldi permitted the detection of deformational features that blurred the visualization of significant diagnostic characteristics in the skull. After elimination of altered conditions in reference to the length snout, shape of premaxilla and architeture of the temporal region and posterior end of the lower jaw, it became possible to offer a revised diagnosis of this species in terms of cranial elements.

The skull here determined as Chanaresuchus sp. by exhibiting a higher degree of distortion, demanded a very detailed evaluation of the taphonomic influence upon the preserved structures. The comparasion with specimens of this genus from Triassic sediments of Argentina facilitated this task, so that the restauration attempted may be considered as provided of a fair degree of confidence. Nevertheless, no significant characteristics for a taxonomic decision at the specific level were detected.

The last ten years have brought an increasingly usage of geobiotic units (local faunas) for determining the biostratigraphical and geochronological characteristics of the Permian and Triassic tetrapod­bearing sediments of Brazil and Argentina. Cerritosaurus binsfeldi (Alemoa Local Fauna) and Chanaresuchus sp. (Pinheiros Local Fauna) confirm the Late Chanarian to Early Ischigualastian and Chanarian ages already attributed to their respective local faunas. This dissertation also presents a review of the results already obtained by means of geobiotic units. Such results proved to be consistent, though the continuation of field work may bring them some adjustments in the future.

TETRÁPODES FÓSSEIS DA FORMAÇÃO SANGA DO CABRAL (EOTRIÁSSICO DO RS)

FOSSIL TETRAPODS OF THE SANGA DO CABRAL FORMATION (EARLY TRIASSIC OF RS)

Rosemary Gomes Santana (1992)

Adviser: Dina Celeste Araújo­Barberena

Abstract

This dissertation deals with the osteological description of fossil remains from the Catuçaba Local Fauna (Sanga do Cabral Formation, Early Triassic of the State of Rio Grande do Sul). The fossils are poorly preserved, owing to the fact that they are found within intraformational conglomerates. Thus, taxonomic determination is difficult. Even so, it was possible to identify some fragments of reptiles and amphibians. Among the remains related to reptiles there are elements such as: maxillae, premaxillae, and a mandibular fragment, ascribed to Procolophon sp.; another mandibular fragment, that shows morphological features common to many procolophonids, but which differs from the genus Procolophon, was therefore classified only at the level of the Family Procolophonidae; a group of ten isolated vertebrae show affinities with those from reptiles of the Order Cotylosauria. Severalamphibian cranial remains, identified upon the only taxonomic criterion available, namely, the ornamentation of the dermal bones, indicated the presence of Order Temnospondyli. Apart from those fragments, identified with reasonable confidence there are other, more problematic. Among them, there is a fragmentary maxilla that could be attributed to the Family Lydekkerinidae, as well as apendicular bones that resemble those from cynodonts and six isolated vertebrae whose morphology does not correspond to any of the groups known in the time interval considered here. This assemblage, containing amphibians and reptiles, indicates a strong correlation between the Catuçaba Local Fauna and the Lystrosaurus Zone of Southern Africa, and equivalent Biozones, specially in Australia and Russia. All of them show a relative predominancy of the amphibians over the reptiles.

A SUBFAMÍLIA COQUIMBINAE OHMERT, 1968 (OSTRACODA) NA PLATAFORMA CONTINENTAL BRASILEIRA - TAXONOMIA, ECOLOGIA, DISTRIBUIÇÕES GEOGRÁFICA E BATIMÉTRICA

THE SUB­FAMILY COQUIMBINAE OHMERT, 1968 (OSTRACODA) IN THE BRAZILIAN CONTINENTAL SHELF - TAXONOMY, ECOLOGY AND GEOGRAPHIC AND BATHYMETRIC DISTRIBUTIONS

Maria Inês Feijó Ramos (1992)

Adviser: Lília Pinto de Ornellas

Abstract

This dissertation comprises, at the specific level, the systematics of the genera Coquimba Ohmert, 1968, Nanocoquimba Ohmert, 1968 and Cornucoquimba Ohmert, 1968 found at the Brazilian Continental Shelf with the respective geographical and bathymetrical distributions and ecological data of the their species. Through the data obtained, eight new species were identified; three of the genus Coquimba: Coquimba ornellasae sp. nov., Coquimba punctata sp. nov. and Coquimba alata sp. nov.; two of the genus Nanocoquimba: Nanocoquimba inflata sp. nov. and Nanocoquimba caudata sp. nov. and three of the genus Cornucoquimba:Cornucoquimba reticulata sp. nov., Cornucoquimba conulata sp. nov. and Cornucoquimba diminuta. It was also registered the presence of Coquimba tenuireticulata Kotzian, 1982 (In: Bertels, Kotzian & Madeira­Falcetta, 1982) emend Sanguinetti, Ornellas & Coimbra (in press) and Coquimba bertelsae Sanguinetti, Ornellas & Coimbra (in press).

The geographical distribution studies of this species made it possible to establish one South association and another one North/East, separated by the Faunal Transition Zone previously established by Coimbra & Ornellas (1989).

MAMÍFEROS FÓSSEIS DO QUATERNÁRIO DO ESTADO DO RIO GRANDE DO SUL, BRASIL

QUATERNARY FOSSIL MAMMALS OF RIO GRANDE DO SUL STATE, BRAZIL

Édison Vicente Oliveira (1992)

Adviser: Jorge Ferigolo

Abstract

This dissertation deals with fossil land mammals from the State of Rio Grande do Sul, correlated to the fauna of Lujanian Age (Late Pleistocene - Early Holocene). Seven new occurrences are reported: cf. Holmesina, Chlamydotherium sellowi?, Glyptodon aff. reticulatus, Neothoracophorus aff. elevatus, Mylodon darwini, Glossotherium (Pseudolestodon) myloides?, and cf. Trigodon. The material, previously described as Plohophorus paivai for the Pantano­Grande locality, and that identified as Megalonychops primigenius for the São Gabriel locality are revised. Some taxa previously referred without description or illustrations to Pampatherium, Propraopus grandis, Doedicurus, Hydrochoerus hydrochaeris and Tayassu, are confirmed by the description of thematerial. On the basis of the data concerning the evolutionary history of the groups, the Great American Interchange, and from the supposed alimentary habits it is concluded that this mammalian fossil fauna of Rio Grande do Sul was composed, predominantly, of grazers probably adapted to open­country environments, like savannas or steppe, and by browsers living in lowlands adjacent to the watercourses. The extinction of the mammals of the Touro Passo and Sanga da Cruz II local faunas may be correlated tentatively to the important environmental changes which occurred between 14,000 and 11,000 years B.P., when a more humid climate, with a more diversified vegetation substituted the colder and dryer climate of the last glacial.

LINHAS DE HARRIS (LH) NO SAMBAQUI ZÉ DO ESPINHO, GUARATIBA­SEPETIBA, ESTADO DO RIO DE JANEIRO, BRASIL, E AS RECONSTITUIÇÕES PALEONUTRICIONAIS E DAS CONDIÇÕES DE SAÚDE PRÉ­HISTÓRICAS

HARRIS' LINES IN THE ZÉ DO ESPINHO SAMBAQUI, GUARATIBA­SEPETIBA, RIO DE JANEIRO STATE, BRAZIL, AND THE RECONSTITUTIONS OF THE PRE­HISTORIC PALEONUTRITIONAL AND HEALTH CONDITIONS

Maria Eloísa Maciel de Almeida (1992)

Adviser: Jorge Ferigolo

Abstract

This dissertation deals with an analysis of tibiae and femora of the Sambaqui Zé do Espinho individuals, looking for Harris' lines (HL), on the basis of radiological studies. The analysis showed the highest percentuals of HL at the distal end of tibiae, following the proximal end of the tibiae and the distal end of femora. The highest percentuals of HL were found at the age intervals in which occurs the greatest osseous growth of individuals, in general between the two and four years, and between ten and sixteen years old, as is usually referred in the literature. Such percentuals can be due to paleonutritional deficits, metabolic impairments or to other diseases proper to these periods. In spite of this, as the highest percentuals were found exactly in the periods of the highest osseous growth, it seems probable that such percentuals were due to some extent to the growth peacks, more than to any other process. Some of these lines can also be the result of multiple and complex biomechanical forces proper to the physical activities developed during such periods of life, and that can be preserved until adult age. The almost complete absence of articular biomechanical studies which could determinate which trabeculae are part of the normal structure of bone, particularly during those periods of the highest physical activities or of important changes in such activities, permit us to suggest the urgent necessity of these studies in living individuals and in laboratory animals. These studies would permit to determinate which trabeculae are part of the normal structure of bone and the ones which could actually be HL, related to paleonutritional, metabolic or resultant of different diseases. Corroborating this observation, it is worthwhile to refer the incongruity between the general contestation of the importance and meaning of the HL in works dealing with extant populations, and the indiscriminated use of the HL by paleopathologists, whose studies have, as a basic aprioristic assumption, that all lines of a certain kind are HL, and that these lines have usually paleopathological implications. This has led to the attribution of deficits and diseases to populations that, on the basis of other evidences such as the alimentary remains and habitats, apparently did not suffer important environmental stressing conditions.

A LIGNITAFOFLORA MESOZÓICA DO RIO GRANDE DO SUL (BRASIL): MÉTODOS DE ESTUDO E CONSIDERAÇÕES SOBRE A TAFONOMIA, PALEOECOLOGIA E PALEOCLIMATOLOGIA

THE MESOZOIC LIGNITAPHOFLORA OF RIO GRANDE DO SUL (BRAZIL): METHODS OF STUDY AND CONSIDERATIONS ON TAPHONOMY, PALAEOECOLOGY AND PALEOCLIMATOLOGY

Robson Tadeu Bolzon (1993)

Adviser: Margot Guerra­Sommer

Abstract

The present dissertation deals with the study of a silicified wood Mesozoic assemblage from Rio Grande do Sul State, Brazil, taking into consideration its taphonomy, paleoecology and paleoclimatology; new methods of anatomical analysis, in face of peculiar conditions of preservation, are introduced. Silicified stumps are found in fluvial sandstones of uncertain age (Upper Triassic or Jurassic) or exposed by erosion and widely scattered over the studied area.

Features created by taphonomic process are associated with the structure of the cells, so that the study by traditional methods results difficult. The fossil wood structure of a stump was analyzed by optic microscope and scanning electronmicroscope. The material micros-copically analyzed includes: anatomical­sections, thin­sections, peels and some smaller fragments chemically attacked by fluoridric acid and the residues of acid attack. In order to determinate the presence of organic matter, one sample was submitted to infrared spectroscopy.

The research revealed that the assemblage is composed of water­transported stumps and wood fragments, representing a globally distributed flora, grown in a warm climate with alternated wet and dry periods. The events of disarticulation, transport and deposition probably were rapid large­scaled episodes while the processes of silicification were slow.

AS FLORESTAS PETRIFICADAS DA REGIÃO DE SÃO PEDRO DO SUL E MATA, RS: INTRODUÇÃO AO ESTUDO DOS PROCESSOS DE FOSSILIZAÇÃO E ANÁLISE MORFOLÓGICA; LEGISLAÇÃO PERTINENTE E ANÁLISE DO DESENVOLVIMENTO DA CONSCIÊNCIA PRESERVACIONISTA

PETRIFIED FORESTS OF THE SÃO PEDRO DO SUL AND MATA REGIONS, RS: AN INTRODUCTION TO THE STUDY OF THE FOSSILIZATION PROCESSS AND MORPHOLOGICAL ANALYSIS; PERTINENT LEGISLATION AND ANALYSIS OF THE DEVELOPMENT OF A CONSCIENCE TOWARDS PRESERVATION

Luiz Fernando Minello (1993)

Adviser: Margot Guerra­Sommer

Abstract

The fossil wood occurrences (Petrified Forests) in the Santa Maria region (cities of Santa Maria, São Pedro do Sul and Mata, RS) represent the largest outcrops of "petrified wood" in Rio Grande do Sul State and, probably, in Brazil.

In this dissertation are discussed the fossilization processes, the development of a preservative conscience among the communities around the occurrences and the legislation regarding this matter. It is presented a tentative of reconstruction of the environmental generator of the paleophytes, based on the characterization of two distinctive paleofloristic assemblages - Xiniquá and Ermida outcrops (São Pedro do Sul, RS).

The petrographic process of lamination of the fossils and their analysis under optical and scanning electron microscopy, among other tests, such as X­ray difratonometry, were performed.

Silica, in distinctive diagenetic phases, associated with impurities like iron oxides, was the predominant mineral in the fossilization process, defined as permineralization.

Gymnospermae fragments could not be classified by means of anatomical studies, owing to their poor preservation. However, affinities to Coniferophyta (sensu Boureau & Nerguerier, 1985) were established, particularly in reference to Araucarioxylon Kraus (1864), if only the characteristics of the secondary xylem are considered. Statistical studies on the external morphology of the fossils from Xiniquá outcrops (São Pedro do Sul, RS) enabled us to artificially establish affinities with Baieroxylon cicatricum Lele Prasad (1984).

The high level of a conscience of preservation among local communities was revealed by the historical investigations. Proposals and proceedings are presented by this study, in order to solve the problems created by the depredatory activities (illegal), which destroy the occurrences.

TAXONOMIA DE BLATTOPTERA (INSECTA, BLATTOPTEROIDA) DA FORMAÇÃO SANTANA, CRETÁCEO INFERIOR DO NORDESTE DO BRASIL

TAXONOMY OF THE BLATTOPTERA (INSECTA, BLATTOPTEROIDA) FROM SANTANA FORMATION, LOWER CRETACEOUS OF NORTHEASTERN BRAZIL

Márcio Mendes (1993)

Adviser: Irajá Damiani Pinto

Abstract

The main object of this dissertation is the taxonomy of the order Blattoptera (Insecta­Blattop-teroidea) from the Crato Member, Santana Formation (Lower Cretaceous), Araripe Basin, State of Ceará. The studied material came from Tatajuba Farm, Santana doCariri District, corresponding to the upper part of the Crato Member, with laminated limestone. The analysis of this paleoentomofaune enable us to create three new genera with nine new species and made comparative and phylogenetic observations upon them possible.