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Contribution to the taxonomic revision of the order Oscillatoriales
HAUEROVÁ, Radka
With the increased use of molecular data, especially the 16S rRNA gene and the following 16S-23S ITS region, many new species and genera have been described in recent years. At the same time, numerous traditional taxa have been recognized as polyphyletic and subsequently subjected to the revisionary process leading to their smaller size and narrower definition. However, there are many species and genera for which no molecular data are available as they were described long before the invent of the sequencing techniques. Thus, it is difficult to allocate their position in the modern phylogenies and move forward with their revisions. This thesis focuses on several simple filamentous cyanobacteria currently classified in the order Oscillatoriales and on the detail study of their type species. The connection of traditional descriptions with corresponding organism results in possibility to obtain reliable molecular data and study the taxa's relationship with other cyanobacteria. Thus, the reference phylogenetic points were established in this thesis for the traditional genera Arthrospira and Oscillatoria, and subsequently two new genera Limnospira and Tenebriella were introduced together with their reference strains. Clarification of the phylogenetic position of the type species of Oscillatoria, O. princeps, means first step towards resolving the polyphyletic nature of the whole order Oscillatoriales and its taxonomic revision.
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Diversity changes in cryptogams along the Scotia arch.
Soukup, Jan ; Frouz, Jan (advisor) ; Hauerová, Radka (referee)
The Scottish Sea and its islands are one of the least explored areas in the world and the least affected areas by human. There are many endemic species of lower plants, thanks to the young geological system and volcanic activity. The study area is located between the northernmost tip of Antarctic continent and the northernmost tip of the South America. Due to its geological and volcanic diversity, this environment offers space for the creation of new young ecosystems, making it an ideal learning area offering extensive research opportunities not only in the diversity of these young ecosystems. This bachelor thesis presents a summary of available sources of lower plants in this area and their spread within islands. As an annex to this bachelor thesis is created a sheet, which represents a summary of representatives of lower plants. Finally, the ability of their dissemination of current and historical significance and the validity of basic ecological principles on the spread and quantity of individual species are discussed. Key words: Scotia Arc; distribution; biogeography; island biogeography; botany; lichens; mosses; liverworts; hornworts; diatoms.
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Aerophytic Cyanobacteria from San Gerardo de Rivas region, San José, Costa Rica
HAUEROVÁ, Radka
The samples of aerophytic Cyanobacteria were collected in tropical cloud forest in Costa Rica from different substrates, such as rocks, wet soil and tree barks. These bluegreen algae have been determined using a light microscope and some of the interesting cyanobacterial species have been also cultivated in the laboratory. Altogether 55 taxa have been found and 8 strains have been isolated for further research. A review on aerophytic Cyanobacteria from the area of the northern part of Latin America and Caribbean has been included as a part of this work.
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