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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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Research of Cenozoic fish faunae of the selected localities of the Czech Republic
Přikryl, Tomáš
The submitted PhD thesis is presented as a collection of commentaries of fish faunas and its paleoecology at 10 selected localities of Czech Republic. The results were supported by specimens also from other geographical regions. The fish faunae were studied on following localities: Kel , Rožnov pod Radhošt m, Liten ice, Krumví , Vážany nad Litavou, Strachotín, Opava - Kate inky, Ku lín u Bíliny, By ov and Bechlejovice. The summarized results: a) There were recognized direct evidences about feeding habits in following taxa from Menilitic and Ždánice-Hustope e formations: Scopeloides glarisianus, Anenchelum glarisianum, Lepidopus glarisianus, Trachinus minutus, Serranus budensis, Merluccius latus, Oligophus moravicus. b) The partial trophic diagram has been constructed within Menilitic and Ždánice-Hustope e formations (for the region of the Czech Republic). The first trophic assemblage (group A) is composed of species Scopeloides glarisianu, Anenchelum glarisianum, respectively Lepidopus glarisianus, gadiform fishes and invertebrate members. The second one (group B) is characterized by species Serranus budensis, argentinid fishes and in some part of European region (e.g. in Poland) also genus Holosteus. The species Trachinus minutus is not possible to include into any of two above mentioned groups for lack of...
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Comparative analyses of cranial skeletogenesis and odontogenesis in basal Ray-finned fishes
Pospíšilová, Anna ; Černý, Robert (advisor) ; Přikryl, Tomáš (referee) ; Buchtová, Marcela (referee)
Skeletal (cartilaginous, bony, and dental) tissues undoubtedly exemplify the key innovation of vertebrates. Among all recent vertebrates, the most numerous and successful lineage is represented by the Ray-finned fishes that, accordingly, exhibit amazing variety of skeletal architectures and phenotypic adaptations. In order to depict fundamental principles of fish cranial skeletogenesis the developmental formation of skeletal architectures was described, compared and analyzed using members of early branching fish lineages, that exemplify very different strategies of skeletogenesis. While the Senegal bichirs and the Tropical gars are heavily armored forms with massive exoskeleton and hyperossified dental structures covering the whole oropharyngeal region, the European sterlets, on the contrary, possess mostly cartilaginous skeleton and reduce their dental structures during early development. Whole analysis is underpinned by the Northen pike, teleostean species with lightened skeletal architecture with comparable number of cranial elements. The present study represents the first complex comparative analysis of their skeletogenesis and odontogenesis. This allowed to define developmental strategies founding different lineage-specific skeletal architecture of vertebrates. Comparative description of...
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Quality of PCB Surface Finishes and Test Coupon Optimization
Minář, Jan ; Přikryl, Tomáš (referee) ; Starý, Jiří (advisor)
This master’s thesis deals with measuring and evaluation of wetting for samples of different surface finishes, using a test coupon developed in cooperation with firm Gatema. It deals with surface finishes ENIG and immersion tin. For these samples deals with quality monitoring and periodic testing of these surface finishes. The solder using for tests is SAC305. Test methods are used for simulation of reflow soldering and wave soldering.
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Fossil marlins (family Istiophoridae) from the Piña locality (Panama; Chagres Formation; Miocene) - morphology and comparison with related forms
De Gracia Castro, Carlos Fernando ; Přikryl, Tomáš (advisor) ; Carnevale, Giorgio (referee)
The study of fossil istiophorids is limited by its fragmentary fossil record; the absence of osteological specimens for comparisons; the cryptic bibliography of several early works and the absence of more accurate comparative methods. Appling a data imputation model we took advantages of extant data for rostral and articular variables for istiophorid billfishes. We used this result to apply PCA analysis and we compared fossil and modern istiophorids together. With this analysis we present here two new istiophorid species: Makaira? sp. nov. 1 and Makaira sp. nov. 2. Makaira? sp. nov. 1 is the most complete fossil istiophorid ever discovered and represent that share characters in various genera. We hypothesize that characters in bones involved in alimentation process have phylogenetic importance as: rostrum shape, denticles, lower jaw, vomer, basioccipital and skull shape as well as orbital size. Our taxonomic reviews of fossil istiophorid reorganize its taxonomy and solve many conflicts about the classification of fossil species. The istiophorids are abundant macrovertebrate in the Chagres sediments and its presence suggests a water column with a minimum of 200m depths in an environment of short platform with oceanic influence. Given the high productivity inferred in this environment we suggest that...
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Vertebrates of the Lower Palaeozoic from the Barrandian area (Bohemian Massif) and their comparison with faunas of adjacent areas
Vaškaninová, Valéria ; Kraft, Petr (advisor) ; Přikryl, Tomáš (referee) ; Trinajstic, Kate (referee)
This thesis deals with early vertebrate fossil remains from the Lower Palaeozoic strata of the Barrandian area (Bohemian Massif). It is presented as a compilation of four papers that were published or submitted in scientific peer-reviewed journals with impact factor. All included papers are focused on the most abundant and diverse vertebrate fauna from the Barrandian area - the placoderms. Placodermi are early vertebrates characterized by articulated head and trunk shields composed of dermal bony plates. In the Barrandian area, they occur exclusively in the Devonian of the Prague Basin. The main objectives of the thesis are modern taxonomic revisions of the placoderm taxa from the Prague Basin as well as discussions about trends in their abundance, diversity, and distribution in space and time, taphonomy, and the evolutionary and phylogenetic implications of their morphology. Two characteristic placoderm associations were distinguished. In the Lochkovian and Pragian, members of the group Acanthothoraci dominate the placoderm record. Acanthothoracid placoderms are among the most basal jawed vertebrates and thus a detailed study of their morphology has a great potential to illuminate the relationships and evolutionary patterns among the stem jawed vertebrates. They are most abundant in the...
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Characterization of cranial skeletogenesis and odontogenesis in basal Ray-finned fishes
Pospíšilová, Anna ; Černý, Robert (advisor) ; Přikryl, Tomáš (referee)
Skeletal tissues represent a key novelty of vertebrates, moreover, structural diversification and phenotypic adaptation of cartilaginous, bony and dental elements determine life strategies of each vertebrate lineage. Ray-finned fishes (Actinopterygii) constitute the most diverse vertebrate group with striking diversity in skeletogenesis and skeletal systems. In this thesis, comparative developmental analyses of craniofacial skeletal tissues and structures in bichirs (Polypteriformes) and sturgeons (Acipenseriformes), was analysed. These basal lineages differ essentially in their strategy of skeletogenesis. Bichirs represent heavily armoured forms with massive exoskeleton, they also comprise thick ganoid scales and dental structures that cover the whole oropharynx. Sturgeons, on the contrary, are primarily cartilaginous fishes with rather reduced skeleton and with teeth that are completely lost during larval development. Skeletogenesis was studied on a unique series of embryonic and larval stages of the Senegal bichir (Polypterus senegalus) and the sterlet (Acipenser ruthenus) by whole-mount staining of their cartilage and mineralized tissues followed by fluorescent microscopy visualisation. Growth dynamics of their skeletal systems was described and compared; expansion of their bony surfaces during ontogeny...
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Miocene fish fauna from the Cheb and Sokolov Basins: taxonomic overview and palaeoecology
Hakalová, Pavla ; Přikryl, Tomáš (advisor) ; Mazuch, Martin (referee)
The aim of this thesis is to present an overview of Miocene fish fauna of the lacustrine sediments in the Cheb and Sokolov Basins, geological settings of this area, and fish associations in individual biozones. Sediments of Cheb and Sokolov Basins were deposited during time interval from Eocene until Miocene in the subtropical zone of the North hemisphere. Volcanic and post-volcanic activities of the Ohárecký rift influenced development of these basins. It's possible define two time sections within development of these basins: early and later; both of them provide rich record of fossil fishes. For the early period of the development is typical smaller range of the lake and its shallow depth. The relicts of this stage are limited to Cheb Basin mainly. Fish fossil record is limited, with three species only: Esox sp., Palaeotinca egeriana and Leuciscus (Palaeoleuciscus) socoloviensis. Low fish diversity could have been affected by poor living conditions or lower taxonomic diversity in general during this time. The later developmental period was much longer. The lake was much bigger - it spread to Sokolov Basin also. The fish fauna diversity is much higher, including taxons Paleotinca egariana, Leuciscus (Palaeoleuciscus) socoloviensis, Aphanius chebianus, Paralebias egeranus and Gobius sp. It is...
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