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Pendent didymograptids of the Šárka Formation (lower Darriwilian) from the Ordovician of the Prague Basin
Strossová, Zuzana ; Kraft, Petr (advisor) ; Mergl, Michal (referee)
Historically, pendent didymograptids of the Šárka Formation belong to less researched group of Palaeozoic graptolites within the Prague Basin. The first occurrence of pendent didymograptids marks the basis of the Oretanian regional stratigraphical stage. Species diversity of pendent didymograptids significantly changed depending on the methodology used. When using the latest methodological approaches in their revision, new significant observations regarding these organisms can be determined. The quality of preservation of particular samples differs considerably; therefore, the application of biometric data in further analyses is limited. After almost 23 years, this thesis represents the first revision of the type material. The systematic part of this diploma thesis focuses on a thorough revision of pendent didymograptids found in shales and siliceous nodules. By applying modern scientific approaches, the lower species diversity of these organisms was determined in comparison to previous studies. The following species are regarded as valid by this thesis: Didymograptus vaccilanoides, Didymograptus artus, Didymograptus cf. bifidus, Didymograptus pseudogeminus and Didymograptus clavulus. Key words: Didymograptus, systematics, Ordovician, Šárka Formation, stratigraphy
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