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Palaeoecological aspects and evolution of the Late Cretaceous oyster assemblages
Rantuch, Jakub
The presented thesis explores the palaeoecological aspects of the evolution of the well-known fossil oyster genus Rhynchostreon Bayle, 1874, a significant representative of Cretaceous fauna. The study integrates sedimentological (quartz grain size), geochemical (concentration of major oxides) and palaeobiological (taphonomy) proxies to categorise five oyster-bearing localities in the Bohemian Massif and the Pieniny Klippen Belt (Western Carpathians) into three environments with differing substrate characteristics, environmental energy levels and salinity regimes. Subsequently, the five specific palaeopopulations of Rhynchostreon suborbiculatum (Lamarck, 1801), occupying these habitats (including the dynamic Cenomanian nearshore, the quiet environment of the Turonian hemipelagic sea and the Cenomanian-Turonian marginal marine system influenced by variable fluvial activity), underwent a series of morphological and population studies. These studies involved the analyses of size-frequency distributions, morphotype structure, and shell thickness. Results from this multidisciplinary approach suggest that the salinity tolerance of R. suborbiculatum may be higher than commonly assumed, and its ecological response to climatic changes (i.e. the fluctuation of salinity, level of eutrophism, etc.) aligns with...
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Lower Cretaceous belemnites (including J/K boundary interval) in the NW Tethys, biostratigraphy, palaeobiogeography and palaeoecology
Vaňková, Lucie
This thesis deals with the belemnite fauna from the Outer Western Carpathians Klippen, its systematic classification, stratigraphical and palaeogeographical evaluation. The palaeontological/palaeobiological approach, together with isotope analyses, including of carbon and oxygen stable isotopes and of strontium isotopes, enabled an integrated investigation of the palaeoecological conditions during the Jurassic/Cretaceous (J/K) boundary interval and the Early Cretaceous age. The Tethyan belemnites are not intensively studied in detail in the J/K interval, as they occur rather rarely in the sections, and/or sedimentary conditions were not suitable for their preservation. Therefore, belemnites are described only from a few sites in the Mediterranean Province. On the basis of recent research, the stratigraphic range of several species previously considered to be from the Tithonian age was extended to the earliest Cretaceous. By contrast, the Lower Cretaceous belemnites (since the late Berriasian) are more abundant. In the classical areas of the Tethyan Realm, it is possible to study the Lower Cretaceous belemnites in great detail and, according to their higher abundance, to determine an individual assemblage corresponding to stratigraphical intervals. Their occurrence is also an important basement for...
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Cenomanian vegetation of the Bohemian Cretaceous Basin
Čepičková, Jana ; Kvaček, Jiří (advisor) ; Teodoridis, Vasilis (referee) ; Spicer, Robert A. (referee)
Cenomanian plant fossils from the Peruc-Korycany Formation of the Bohemian Cretaceous Basin, Czech Republic are described, analysed and their palaeoenvironment is interpreted. Cycad foliage Nilssonia mirovanae Čepičková et J.Kvaček including micromorphology of its cuticle was described. It shows deeply sunken stomatal apparati surrounded by papillae overhanging the stomatal pit. The haplocheilic stomata are arranged in rows. Todziaphyllum saportanum (Velen.) Čepičková et J.Kvaček is a serrate-margined leaf with semicraspedodromous venation. Since the cuticle of this plant fossil has not been preserved, macro-observation is the only method available. Ascarinophyllum pecinovense Čepičková et J.Kvaček is a serrate-margined leaf, having an abaxial cuticle covered by striations, randomly oriented, and radially oriented striations around the stomata. This species shows a combination of laterocytic/laterocyclocytic, stephanocytic-bicyclic, amphibrachyparacytic, less frequently brachyparacytic and holoparacytic stomata, sometimes with T-shaped thickenings of the internal cuticle at the poles. Papillaephyllum labutae Čepičková et J.Kvaček is characterised by leaves with serrate margins. It shows an abaxial cuticle covered by large papillae. Its stomatal apparatus shows a combination of latero-cyclocytic and...
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Palaeoecological aspects and evolution of the Late Cretaceous oyster assemblages
Rantuch, Jakub ; Košťák, Martin (advisor) ; Mergl, Michal (referee) ; Reháková, Daniela (referee)
The presented thesis explores the palaeoecological aspects of the evolution of the well-known fossil oyster genus Rhynchostreon Bayle, 1874, a significant representative of Cretaceous fauna. The study integrates sedimentological (quartz grain size), geochemical (concentration of major oxides) and palaeobiological (taphonomy) proxies to categorise five oyster-bearing localities in the Bohemian Massif and the Pieniny Klippen Belt (Western Carpathians) into three environments with differing substrate characteristics, environmental energy levels and salinity regimes. Subsequently, the five specific palaeopopulations of Rhynchostreon suborbiculatum (Lamarck, 1801), occupying these habitats (including the dynamic Cenomanian nearshore, the quiet environment of the Turonian hemipelagic sea and the Cenomanian-Turonian marginal marine system influenced by variable fluvial activity), underwent a series of morphological and population studies. These studies involved the analyses of size-frequency distributions, morphotype structure, and shell thickness. Results from this multidisciplinary approach suggest that the salinity tolerance of R. suborbiculatum may be higher than commonly assumed, and its ecological response to climatic changes (i.e. the fluctuation of salinity, level of eutrophism, etc.) aligns with...
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Scientific reconstruction of theropod dinosaurs
Cettl, Karel ; Mazuch, Martin (advisor) ; Marek, Jaroslav (referee)
To create a good scientific reconstruction is important artistic skills and knowledge of history painting of prehistoric animals, and also knowlages in the anatomy, zoology, palaeontology, palaeoecology. Reconstruction of theropods dinosaurs became the royal discipline of professional illustration. It stands on the borderline between art and science. Our view on theropod dinosaurs has changed over time with advancing skeletal findings, and also changed a scientific reconstruction. Keywords: theropods, scientific reconstruction, anatomy structure, palaeoecology, Carnotaurus sastrei.
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Crustacea (Decapoda, Cirripedia) from the Bohemian Cretaceous Basin
Kočová Veselská, Martina ; Košťák, Martin (advisor) ; Krobicki, Michal (referee) ; Schweigert, Guenter (referee)
This thesis deals with systematic revision, evolutionary trends, palaeoecology and migration patterns of crustaceans (Cirripedia and Decapoda) from the Upper Cretaceous of the Bohemian Cretaceous Basin. Thesis is presented as a compilation of 9 papers that were published in scientific peer-reviewed journals and includes not only old museum material, but also numerous crustacean specimens which have been recovered in the last decade. Besides, short remarks on fossil crustaceans currently under study or in the process of being published (Paraclythia, Oncopareia, Acrothoracica) are also included in this thesis. In view of the fact that the fossil crustaceans from the BCB were most recently recorded in the turn of the 19th and the 20th centuries (and partially revised in the first half of the 20th century) and since the systematics and taxonomy have changed significantly, all papers presented here focus primarily on systematic revision and modern description. The essential part of the thesis thus deals with taphonomy and its bearing on the identification of fossil material. Thanks to a modern description, new species of Ctenocheles fritschi (axiidean shrimp), Archaeochionelasmus nekvasilovae (acorn barnacle), Myolepas reussi and Capitulum sklenari (pedunculate barnacles) were erected. C. fritschi is...
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Relationship between pollen diversity and floristic diversity - utilization for study of the past
Koďousková, Lucie ; Kuneš, Petr (advisor) ; Prach, Jindřich (referee)
This thesis deals with the relationship between palynological diversity and floristic diversity. Diversity is complex quantity, which consists of a number of species, the number of individuals and relative frequency of species known as evenness. It characterizes the diversity at the species level, genetic level or within communities. Its relationship with palynological diversity is problematic, especially because of lack of taxonomic precision in palynology, species-specific differences in pollen production and dispersal and sample size, since the number of taxa increases with sample size. The thesis also focuses on the studies which tried to prove positive correlation between palynological and floristic diversity, including techniques used. The second part describes methodology of collecting vegetational and palynological data and the treatment of sampes.
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Analysis of selected fish coprolites from the Loučka locality (Moravia; Oligocene, "menilitic Formation")
Vala, Vladimír ; Přikryl, Tomáš (advisor) ; Zajíc, Jaroslav (referee)
The submitted thesis deals with the analysis of selected fish coprolites found in the Loučka site (Moravia; Menilite Fm.). Eleven specimens was selected (provisionally numbered I-XI) of which two were macerated (specimens I and II). The remaining nine specimens were examined at the surface of the sedimentary layers. Recognizable elements were classified to the following taxa: Keasius parvus, Alopias exigua, Squalus cf. alsaticus, Sardinella sardinites, Anenchelum glarisianum, Palimphyes sp., Palaeogadus sp., Gonostomatidae (gen. et. sp. indet.), Perciformes (gen. et sp. indet.), and Teleostei (gen. et sp. indet.). Composition of the studied coprolites I, II and IV suggest that these were produced by shark species Alopias exigua and Squalus cf. alsaticus. Studied coprolites V, VIII, X and XI were produced by some type of undetermined predatory fish (probably piscivore predator). For coprolites III, VI, VII and IX producer can not be determined.
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Oyster bioherms in the Bohemian Cretaceous Basin
Rantuch, Jakub ; Košťák, Martin (advisor) ; Frank, Jiří (referee)
Frustration from shape and size variability of oyster's species Rhynchostreon suborbiculatum (Lamarck) is long known phenomenon. In current state of his systematic it is not possible to consider it fully satisfying. Is it is shown in study of genus Gryphaea by Jones and Gould (1999), that application of modern analytical methods, undoubtly lightens long-darkned places of evolution process. Idea of Videt and Neraudeau (2003), that shape variability of Rhynchostreon suborbiculatum (Lamarck) probably also mirrors heterochronic processes, introduces inspirative and good foundation for future research in this field. Occurence of this oyster is proved from huge range of sites in Bohemian Cretaceous Basin area. It is combination of rich occurance, unique preservation and variability of lithological settings, which gives us unique starting point for next step to solve significant problem. Based on population analyses consisting of biometrical studies supported by oxygen isotope analyses, in future, it will be possible to reach sufficient conclusions of this issue, and progress in our knowledge.
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Lower Cretaceous belemnites of the locality Štramberk: taxonomy, stratigraphy, palaeoecology, palaeobiogeography
Vaňková, Lucie ; Košťák, Martin (advisor) ; Vašíček, Zdeněk (referee)
The study (MS, diploma thesis) is based on more than 1200 belemnite rostra set from the Lower Cretaceous sediments of locality Štramberk (N Moravia). Investigated rostra come from the collection of Dr. V. Houša, who collected them during the seventies to eighties of the last century, during intensive excavation of the Lower Cretaceous tectonic block named Š-12 "pocket". Belemnite rostra were determined at species and generic levels including 7 species and 18 genera. The majority of belemnite assemblage comes from the Lower Valanginian strata, however, also the Tithonian, Berriasian and Hauterivian taxa are present, what clearly documents the redeposition. The presence of mesohibilitids, known from the Barremian and younger deposits, still remains enigmatic. For better understanding of the redeposition proces, the alveolar infill formed by several generations of sediments, are investigated. Study of these sediments outlines the sedimentary development of the Baška elevation inside the Outer Carpathian system. Preliminary stable isotope data δ18 O and δ13 C received from belemnite rostra show different belemnite life-style during the ontogeny - i.e. juvenile bottom life style and adults inhabiting shallow/warmer waters. Negative values of δ18 O should be correlated with the "Valanginian extinction...
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