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The parareptilian group Procolophonoidea has been increasingly studied in recent years, and a high survival rate during the P/Tr extinction event has been estimated tor the ciade. Procolophonoid interrelationships, however, remain poorly known. Here, descriptions of the procolophonids Anomoiodon liliensterni and Leptopleuron lacertinum, and the possible Permian Russian procolophonoids, are provided. Anomoiodon and the genus Kapes were found to be closely related but there is not enough evidence to support the synonymy of the two genera. Leptopleuron is described in great detail, making it one of the most completely knovm procolophonoids. Of the possible Permian Russian procolophonoids, Suchonosaurus minimus was found to be a member of the more inclusive Procolophonidae, whereas Microphon exiguus and Kinelia broomi fall outside of Procolophonoidea. Nyctiphruretus acudens might be the sister taxon of Procolophonoidea but an alternative hypothesis of Nyctiphruretus being more closely related to pareiasaurs and nycteroleterids also received support, A phylogenetic study. including 39 procolophonoid taxa, was conducted. The results suggest novel compositions of the procolophonid clades Leptopleuroninae and Procolopphoninae; the monophyly of the genus Kapes was questioned; the phylogenetic position of Suchonosaurus, Pintosaurus and Phaantosaurus among the other basal procolophonids remains unresolved; and the results cast doubt on Procolophonoidea being divided into the clades Owenettidae and Procolophonidae. The topology with the best stratigraphic fit indicates that only 57% of procolophonoid lineages might have survived through the P/Tr boundary. However, it is also possible that up to 80% lineages crossed the boundary but this requires a scenario that maximizes the number of ghost lineages. A stratigraphical analysis supports separate Owenettidae and Procolophonidae.

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No description available.

A Dissertation submitted to the Faculty of Science, University of the Witwatersrand, in fulfilment of the requirements for the Degree of Master of Science Johannesburg, 2015 / The Chiniquodontidae is a family of Triassic carnivorous cynodonts well represented in the Middle-Upper Triassic of Argentina and Brazil. Chiniquodontids were more recently discovered in Madagascar and central Namibia, representing the only record of the family outside South America. The Namibian specimen was discovered in the Upper Omingonde Formation and is represented by the skull and a partial skeleton. The new chiniquodontid was identified as Chiniquodon and is diagnosed by the postcranial characteristics identified; a strong bend in the proximal portion of thoracic ribs, reduced curvature of the clavicle, although this may be due to deformation, robustness of the neck of the ilium, differences in the angulation between the edge of the posterior lamina of the ilium and the margin of the neck, and a large ischium, which is more than twice the size of the pubic plate. The postcranial material of the chiniquodontid from Namibia is described and compared with that of South American chiniquodontids. Chiniquodontids lack costal plates on ribs, show a tall and slender scapular blade, a large acromion process positioned well above the scapular neck and absence of disc-like phalanges in the autopodium. The Namibian Chiniquodon provides the first evidence of elements from the pes in chiniquodontids, and one of the few for non-mammaliaform cynodonts. Sedimentological studies confirm that the Upper Omingonde Formation of Namibia represents fluvial deposits of braided and meandering rivers formed in a predominately arid climatic regime during the Middle Triassic.

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ABSTRACT This study presents a taxonomic revision of some procolophonoid parareptiles and a detailed, global analysis of procolophonid intrarelationships. The poorly known genus Candelaria, from the Middle Triassic of Brazil, is identified on the basis of new material as an owenettid, rather than a procolophonid as previously thought. Thus, Candelaria represents the youngest owenettid and the first member of this group from South America. The cranium of Candelaria is also remarkable for having temporal fenestrae, and the significance of this character within the Parareptilia is discussed. Based on a comprehensive review of specimens referred to different Procolophon species, it is proposed that only the type species, Procolophon trigoniceps, is valid. Thus, Procolophon specimens from Brazil, South Africa, and Antarctica are all referable to P. trigoniceps. Consequently, P. trigoniceps has one of the broadest known geographic ranges among Triassic tetrapod species. A comprehensive cladistic analysis of procolophonids more firmly resolves the relationships within that group. The analysis reveals that Procolophoninae and Leptopleuroninae are valid monophyletic groups, whereas Spondylolestinae is paraphyletic. The species formerly assigned to the genus ‘Thelegnathus’ from the Middle Triassic of South Africa, and those assigned to ‘Eumetabolodon’ from the Lower-Middle Triassic of China, are paraphyletic. The poorly known Spondylolestes from the Dicynodon Assemblage Zone of South Africa is considered valid and possibly represents the only Permian procolophonid in Gondwana. A new species, Kitchingnathus untabeni, is identified in the Lystrosaurus Assemblage Zone of South Africa. It is a basal member of the Procolophonidae and co-occurs with Procolophon in the Upper Katberg Formation. The new taxon is characterized by the presence of a large number of thin, bicuspid teeth. Character optimisation indicates that bicuspid teeth were acquired independently in K. untabeni, and hence originated twice during procolophonid evolution. A review of procolophonid records worldwide reveals a fossil hiatus for members of this group in the Ladinian and most of the Carnian.

A B S T R A C T The rocks of the Beaufort Group of South Africa record a remarkably complete depositional sequence incorporating a rich fossil tetrapod succession from the mid-Permian to mid-Triassic. This represents one of the best preserved ecological assemblages of pre-mammalian terrestrial tetrapods documenting the stem lineages of both mammals and dinosaurs. For more than a century large collections of fossils from the Beaufort Group have been built up at various museums in South Africa. With the co-operation of all the South African museums curating collections of Karoo fossils, a single standardised database has been compiled for the fossils collected from the Beaufort Group as well as a GIS system incorporating all the South African databases of fossil records. Major problems which had to be overcome related largely to the non-standardised nature of different databases, locality, and taxonomic information. Particularly problematic was entering ambiguous and vague locality information onto the GIS database, so that it would still be useful for qualitative evaluation. The created GIS database is a useful analytical tool, but requires streamlining to make it accessible to all users. Completion of the foundation phase of the GIS database has highlighted problems which need to be addressed in the future to make the database an effective tool for research purposes.

The Nigerian anorogenic province is characterised by more than 50 complexes. In some complexes, the outer limits of the complexes are defined partly or completely by a ring dyke. This intrusion, generally composed of granite porphyry, was the chief structural element of the complex and controlled the distribution of both volcanic and subvolcanic magmatism at high levels in the crust. The complexes are exposed at different erosional levels: in some complexes, particularly in the north, the volcanic products are preserved through caldera collapse. The majority of the volcanics are dominantly rhyolitic, some alkaline centres have preserved occasional successions of hawaiites, mugearites and trachytes confirming the dominantly alkaline trend from transitional ne-normative or ne-normative basalts. In other centres the volcanic cover has been removed so that the subvolcanic granites and syenites have been exposed. The subvolcanic assemblages include minor gabbros, monzogabbros and syenites. However granitic rocks are overwhelmingly dominant with fayalite hedenbergite granites, amphibole granites and syenites, albite-rich and albite-poor aegirine arfvedsonite granites and biotite granites. As far as the granites are concerned there was a natural progression from volcanic feeder intrusions to subvolcanic intrusions with fayalite and hedenbergite. The volcanic feeder intrusions were an important link during the caldera-forming stage between the subvolcanic roots and the overlying volcanic pile. They are represented by quartz and granite porphyries. The mineralogical assemblages of many of these complexes however, is often the result of interaction with residual fluids. Fluids affected the late magmatic and particularly the postmagnatic (subsolidus) crystallisation history of a cooling subvolcanic pluton and to some extent the overlying volcanic pile. Such hydrothermal alteration has undoubtedly modified the original granite chemistry. The residual fluids which were responsible for hydrothermal alteration also carried ore metals which were variously deposited at different stages of hydrothermal alteration. Mineralisation of a pluton generally occurred in the apical or marginal zones or in satellite dykes. Different styles of mineralisation tend to characterise different parts of a granite pluton and five separate zones have been recognised; the roof, marginal and contact zones of a pluton, the enclosing or overlying rocks and the surrounding ring dyke. Nine different styles of mineralisation have been identified including pervasive metasomatic disseminations; pegmatitic pods and lenses; stockworks and lodes. No particular type of hydrothermal alteration is restricted to one particular style of mineralisation and it is possible to have disseminated sodic, potassic, acid or silica metasomatism and altered ring dykes may show the effects of all these processes. The complexity of the subsolidus mineralogical re-equilibration has been appreciated by a detailed study of the Rishi area of the Saiya Shokobo caiplex. The Saiya Shokobo complex forms a distinctive hill mass in north central Nigeria which covers an area of approximately 250km. The main structural feature of the complex is the elliptical fracture 17km in diameter which has largely determined the outline of the central massif of the Saiya Shokobo Hills and has controlled the emplacement of several of the intrusions of the complex. The complex is dominated by volcanic rocks which are confined within this elliptical fracture. During the latest stage of magmatic activity, the emplacement of a granite pluton moved beyond the confines of the main fracture and was intruded eccentrically to the north east of the main part of the complex. Thus the biotite granite intruded both its own volcanic pile and the basement hornblende biotite monzogranite.

Sediments referred to the Trias outcrop at intervals over a distance of 105 miles (157 km) along the northwestern seaboard of Scotland. A detailed description is given of the field occurrences and successions, and the stratigraphy revised. Important rod sediments in Westor Ross, previously mapped as Trias, are shown to be Torridonian and their significance is discussed. The Trias is very variable in thickness ranging from negligible to over 300 m (1000 ft). Lithological units show rapid lateral variation, and it is impossible to draw detailed comparisons between successions in different areas. The sediments mainly consist of conglomerates and sandstones which are compared of materials derived from formations, known in the area at the present time. The study of textures and sedimentary structures shows that the sediments are fluviatile. Piedmont deposits and sediments which accumulated in an environment intermediate between piedmont and valley-flat are common true valley-flat deposits also occur, represented by thin fine-grained said-stones and siltstones, Concretionary limestones occur throughout the area, except in one locality, find are interpreted as pedocals. The sediments probably, accumulated in a series of partially isolated basins. Sedimentation was influenced early on by a chain of upland area consisting of n sequence, of Torridonian and Cambro-Ordovician sediments which extended from Loch Broom to Iona, west of the present outcrop of the Hoine Thrust. Source areas to the east became dominant later. The climate was probably hot and semi-arid, with seasonal rainfall.