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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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Taphocoenoses with spongens in the Bohemian Cretaceous Basin
Vodrážka, Radek ; Košťák, Martin (advisor) ; Pisera, Andrzej (referee) ; Skupien, Petr (referee)
This PhD thesis annotate a compilation of published papers, which deal with sponge-bearing taphocoenoses in the Bohemian Cretaceous Basin (BCB) and with techniques of their study. Essential platform for dealing with this topic represent: a) study of distribution of sponges in the BCB b) study of basic fossilisation processes of sponge skeletons c) study of various laboratory techniques for preparation of sponges and other invertebrates from the BCB; practising and improving these methods d) study of sponge-bearing localities in the BCB based on filedwork and study of literature and fossil material housed in Czech and foreign palaeontological collections e) study of selected taphocoenoses from sponge-bearing localities in the BCB - i.e. Upper Cenomanian to Middle Coniacian localities Part of PhD thesis summarize recent state of knowledge in palaeontological/geological studies of sponge-bearing localities and include also new information about taphocoenoses with sponges in the BCB. This information is based on (1) new (unpublished) author data, (2) author's and co-authored publications published during PhD studies (referenced but not presented in PhD thesis) and (3) co-authored submitted paper. The most important results are presented to be abstracts of published papers (see below). Publication list with...
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Palaeoecological aspects of Rhynchostreon Bayle oyster evolution
Rantuch, Jakub ; Košťák, Martin (advisor) ; Juřičková, Lucie (referee)
This paper presents a multilevel analysis of palaeoecological aspects of the process of the Rhynchostreon genera evolution. According to the latest results of research, the process of genus appears to be more dynamic than previously assumed.The processes of internal dynamics of the environment in conjuncture with other studied aspects of the late cretaceous environment (e.g. paleotemperature, salinity, etc.) were a significant factor that initiated the activity of selective pressure and represents an important factor in group evolution. In this work we provide the overall hypothesis about co-evolution of two intrageneric (sisters) lineages in Rhynchostreon genera. The definiton of evolutionary trends of intrageneric lineages within the presented hypothesis (including a new description of oyster species) is supported by various analytical methods, which anchors them in the current zoological nomenclature system. An electron microscopy, isotopes and biometrical analysis of a shell in cooperation with some of the sedimentologic methods suggest a relation of lithology (as a result of environmental aspect) and evolution process. The transregional concept of proposed ecological-evolutionary models, based on materials studies from various paleogeographic regions of cretaceous world, increases the...
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Lower Cretaceous belemnites (including J/K boundary interval) in the NW Tethys, biostratigraphy, palaeobiogeography and palaeoecology
Vaňková, Lucie ; Košťák, Martin (advisor) ; Michalík, Jozef (referee) ; Fozy, István (referee)
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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Sytematics, palaeoecology and trophical structure of bivalve associations within the OAE2 in the Bohemian Cretaceous Basin (Upper Cenomanian): Pecínov quarry
Kunstmüllerová, Lucie ; Košťák, Martin (advisor) ; Čech, Stanislav (referee)
Title: Sytematics, palaeoecology and trophical structure of bivalve associations within the OAE2 in the Bohemian Cretaceous Basin (Upper Cenomanian): Pecínov quarry Author: Bc. Lucie Kunstmüllerová Department: Institute of geology and palaeontology Supervisor: doc. RNDr. Martin Košťák, Ph.D. Abstract: This master thesis provides an updated taxonomic inventory of the bivalve fauna of the Pecínov locality, places the fauna in its palaeobiogeographic setting, and addresses its palaeoecological significance. In the literature research part of the thesis the basic geology of the locality and an overview of the Bohemian Cretaceous Basin are presented. Processes connected to the ocean anoxic events, specifically to the OAE 2 are also discussed. The research part of the thesis describes the systematics of the bivalve assemblage (with the exception of Inoceramidae) and its statistical evaluation with the emphasis on the environment interpretations of the locality. In total, over 350 specimens have been considered and assigned to 20 genera within 15 families and 9 orders. Bivalve functional morphology and guilds are described to interpret palaeoecology. Guilds are based on life habit and feeding category. Four main guilds are recognized: epifaunal suspension-feeders, semi-infaunal suspension-feeders, infaunal...
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Cephalopod jaws from the Bohemian Cretaceous Basin - taxonomy and stratigraphic implications
Kozlová, Zuzana ; Košťák, Martin (advisor) ; Vašíček, Zdeněk (referee)
This work is focused on systematic research of cephalopod jaws from the Late Cretaceous. Samples of 147 newly recorded nautiloid rhyncholites from the Bohemian Cretacoeus Basin and one new ammonite rhyncholite from Řepov village were systematically analyzed. The new collection of lower ammonite jaws (aptychi) consists of 32 specimens. Nautiloid rhyncholites from localities Turkaňk, Úpohlavy, and Dreisen were determined as Nautilorhynchus simplex. Conchorhynchs from locality Vinary u Vysokého Mýta belong to the species Conchorhynchus cretaceous, which is associated with the commonmost species Eutrephoceras sublaevigatum. Ammonite rhyncholite is left in the open nomenclature due to its uncertain systematic position and it is not assigned to any ammonite species. Records of aptychi from the locality of Úpohlavy and Pecínov represent mainly species of heteromorphic ammonites - baculitids (Baculites, Sciponoceras). The total diversity of species from both localities reaches 20 ammonite species. The two jaw morphotypes (2 species of aptychi) are reported from the Bohemian Cretaceous Basin for the first time herein. Of the high importance, it is a record of ammonite Prionocyclus germari from Úpohlavy with associated lower jaws in situ within the body chamber. Aptychus of this taxon has never been...
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The Jurassic belemnites of northern Bohemia - stratigraphy, palaeobiogeography and possible isotope record
Geist, Jan ; Košťák, Martin (advisor) ; Frank, Jiří (referee)
4 Abstract The work is based on a revision of collection from several scientific institutions from the Czech Republic and the Federal Republic of Saxony (National Museum in Prague, Chlupáč Museum of Earth History, Senckenberg Natural History Collections Dresden, etc.). The collection is based on samples published by Oskar Lenz and George Bruder from the second half of the 19th century. Both authors also processed the findings of other researchers (e.g. Cotta, Weisse). The belemnite rostra were systematically divided into four families, five genera and seven identifiable genera. One rostrum has not exactly been determined. The age of the samples was established to be the Middle and Upper Jurassic (Bajocian- Kimmeridgian). The length of the expected sedimentation in this area has been prolonged to the past (deeper to the Middle Jurassic), mainly due to the finding of the species Megateuthis gigantea Schlotheim, 1820. Earlier research (especially in the 20th century) assumed the extent of preserved carbonate rocks only in the Oxfordian and Kimmeridgian age, with a not much fossiliferous Callovian Brtníky Formation. The studied sedimentary rocks show a significant influence of Milankovich cycles with repeated alternation of carbonate and non- carbonate layers in the sequence. Preliminary results of isotope...
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