Cretaceous ferns from Australia and Antarctica

• Main Author: Nagalingum, Nathalie S
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: University of Melbourne 2002
• Subjects: Ferns; Fossil > Australia; Fossil > Antarctica Paleobotany > Cretaceous; Alexander Island; Antarctic; Antarc*; Antarctica
• Online Access: http://hdl.handle.net/11343/341554

Typescript (photocopy) Thesis (PhD) -- University of Melbourne, Department of Botany, 2003 Includes bibliographical references (leaves 209-234) Ferns were an important component of Cretaceous vegetation. They are preserved as foliage and spores, and this investigation utilises both of these remains to study the Cretaceous record of ferns in Australia and Antarctica. The Albian, Alexander Island, Antarctica assemblage comprises 25 fern taxa incorporating Osmundaceae, Matoniaceae, Dipteridaceae, Gleicheniaceae, Marsileaceae, and possibly Dicksoniaceae. In this flora eleven new species are described (Phyllopteroides antarctica, Matonia jeffersonii, Tetragleichenites acuta, Regnellidium peninsulaensis, Cladophlebis dissectus, Cladophlebis drinnanii, Cladophlebis macloughlinii, Microphyllopteris unisorus, Sphenopteris sinuosa, Adiantitephyllum serrata, and Pedata alexanderensis) and three genera are erected (Pedata, Adiantitephyllum and Tetragleichenites). At Victoria, Australia, there are 36 fern taxa occurring in the Neocomian-Albian, including representatives of Osmundaceae, Dicksoniaceae, and Marsileaceae. In the Victorian assemblages there are four new species (Marsilea cantrillii, Aculea angustifolia, Aculea brevipinnata, and Aculea dichotoma), two new species combinations (Sphenopteris dispersus and Aculea bifarius), and one new genus (Balookana). There is a large number of fern species shared between Victoria and Alexander Island compared to assemblages from elsewhere in Gondwana; this may be related to the high latitudinal positions and consequent climatic similarities of these areas. Trends in Australian and Antarctic Cretaceous palynomorph diversity and abundance reveal there were large declines in free-sporing plants, a rapid increase in angiosperms in the Late Cretaceous, and smaller reductions in gymnosperms throughout the period. Of the constituent free-sporing plant groups, only lycophytes and ferns decreased (in the Early and Late Cretaceous respectively), whereas bryophytes increased ...