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Ontogenetic development of Cambrian eocrinoid echinoderms of the Barrandian area
Nohejlová, Martina ; Fatka, Oldřich (advisor) ; Valent, Martin (referee)
This diploma thesis presents the first study focused on the ontogenetic development of eocrinoid echinoderms in the Czech Republic. Parsley's work (2012) on ontogeny of the genus Gogia from south China is the model study. The aim of this thesis is a comparable study of ontogeny of eocrinoid echinoderms from Cambrian of the Barrandian area. Akadocrinus jani Prokop, 1962 was studied. Using detailed morphological description and measurement of various parameters, three different ontogenetic stages have been established: juvenile ontogenetic stage, mature ontogenetic stage and gerontic ontogenetic stage. Thecal height is the deciding factor for the determination of the specific ontogenetic stage. Further, during ontogeny of this species some trends in changes in the size of body parts are observed (e.g., changes in the diameter of thecal plates). In-depth study of morphological details showed that the originally distinguished two species, Akadocrinus jani Prokop, 1962 and Akadocrinus nuncius Prokop, 1962, represent one species only. Keywords: eocrinoid echinoderms, Akadocrinus jani, ontogeny.
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Latest Ludlow chitinozoans from the Prague Basin: significanec for correlations and succession during Kozlowskii/Lau extinction events
Vodička, Jakub ; Fatka, Oldřich (advisor) ; Štorch, Petr (referee)
Two sections, Všeradice and Kosov, represent continuous sedimentary succession situated in the Prague Basin. No detailed research on stratigraphical level equal the N. kozlowskii graptolite zone focusing on chitinozoans, has not yet been conducted in the Prague Basin and is also very scarce globally. Limestone beds, examined for chitinozoans, were not very productive. Chitinozoan reaction on extinction is visible, if we compile data from both sections. The pre-extinct chitinozoan fauna is characterized by the Conochitinidae family. Samples from the post-extinct interval contained no chitinozoas. The interval of fauna recovery is characterized mainly by the Eisenackitina genera. In this interval, global zone for the uppermost Ludfordian, represented by E. barrandei, can be confirmed. In agreement with all the published literature, we have not found E. philipi, index taxa of the former global zone in the Prague Basin. E. lagenomorpha appears stratigraphically only slightly below E. barrandei and therefore it cannot substitute E. philipi, as it is used in Baltika region. chitinozoa, Prague Basin, Kozlowskii, Lau, extinction, Ludfordian, stratigraphy
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Ontogeny of Sao hirsuta (Barrande, 1846) in the Cambrian of Czech Republic: revision
Laibl, Lukáš ; Fatka, Oldřich (advisor) ; Kleisner, Karel (referee)
The Solenopleurid trilobite Sao hirsuta Barrande, 1846 is known from "Middle" Cambrian sedimentary rocks of the Czech Republic, Germany and Spain. It is one of the first trilobites on which ontogenetic development was described in detail (Barrande, 1852). This diploma thesis is the first modern revision of the ontogeny of this species for more than fifty years. Thesis is primarily based on quantitative methods and a detailed study of morphology of the exoskeleton. Changes in the dorsal exoskeleton during ontogenetic development of S. hirsuta, including the discovery of intrainstar morphological and size variability and the transition from isometric growth to the alometric growth, were described in detail by using quantitative methods (biometric measurements and geometric morphometrics). In the protaspid period different instars of S. hirsuta were recognized. Detailed morphological studies revealed several different morphotypes of protaspid stages. Some of which may represent different taxa. The morphology and the condition of the hypostome was described, including changes of hypostome during ontogeny. The study of segmentation in the species S. hirsuta shows hypoprotomeric development with the initial accumulation phase, middle equilibrium phase and terminal depletion phases. Key words: Sao...
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Ontogeny of trilobites
Laibl, Lukáš ; Fatka, Oldřich (advisor) ; Budil, Petr (referee)
The thesis summarizes the current state of knowledge about the ontogeny of trilobites. The introductory chapters describe the basic morphology and anatomy of trilobites, and also mention their ecology, occurrence and feeding habits. In the main part of my thesis, I first summarized the existing research in this area, and also dealt in detail with methods of preservation of trilobite larvae, their reproduction, growth, embryology, postembryonal development, segmentation and ecology. I also mentioned the possible usage of this knowledge in other fields (stratigraphy, biogeography, etc.). The last section is a contemporary view on the systematics of trilobites and their position within the Arthropoda.
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Systematics of eocrinoid echinoderms
Nohejlová, Martina ; Fatka, Oldřich (advisor) ; Polechová, Marika (referee)
This work deals with systematics of eocrinoid echinoderms but also with their morphology and classification within the echinoderms. Two theories concerning systematic of eocrinoid echinoderms are compiled in this work. UBAGHS (1967) suggested the first version of systematics. SPRINKLE (1973) suggested the second one, still used version of systematics. Work is also focused on the occurrence of eocrinoid echinoderms in Cambrian and Ordovician rocks of the Barrandien area.
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Hyoliths of the Barrandian area
Valent, Martin ; Fatka, Oldřich (advisor) ; Mergl, Michal (referee) ; Vašíček, Zdeněk (referee)
of Mgr. Martin Valent doctoral thesis Hyoliths of the Barrandian Area The submitted Ph.D. thesis summarizes recent information on comparatively poorly known group of invertebrates - the hyoliths. The first part of the thesis is composed by six main chapters focussed in detail on various aspects of hyoliths; major characteristics and ecology of hyoliths, progress in systematic of hyoliths, principles of hyolith classification, stratigraphical and palaeogeographical distribution of hyoliths, hyoliths within the Bohemian Massif and morphology of hyoliths. Up-to-date information has been included in all chapters. New data were published in five author's papers on hyolith colour patterns, systematics of hyoliths, pattern of palaeogeographic distribution and palaeoecologic interactions between hyoliths and various elements of the Cambrian invertebrate fauna. Short appendage consists of the Czech-English-Chinese terminological dictionary, simplifying study of Chinese literature.
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