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Rinistachya Hilleri
''Rinistachya'' is a genus of Late Devonian Sphenopsida, sphenopsid, currently containing one species, ''Rinistachya hilleri''. It comprises the only sphenopsid as yet known from the Devonian of Gondwana, and is currently known from only a small number of specimens collected from the main fish layer/lens (MFL) black shale within the Witpoort Formation (Witteberg Formation, Cape Supergroup) at Waterloo Farm, Makhanda. It is currently interpreted as a small-sized herbaceous plant. and 'exhibits a novel architecture' that includes apparently plesiomorphic characters, reminiscent of the organisation of the Iridopteridales (including the production of two types of laterals at one node, the location of fertile parts in loose whorls on lateral branches and an organisation of the fertile parts in which they branch several times before bearing distally elongate sporangia). Other characters unambiguously nest ''Rinistachya'' within the Sphenopsida (including presence of planate and sligh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphenopsida
Equisetidae is one of the four subclasses of Polypodiopsida (ferns), a group of vascular plants with a fossil record going back to the Devonian. They are commonly known as horsetails. They typically grow in wet areas, with whorls of needle-like branches radiating at regular intervals from a single vertical stem. The Equisetidae were formerly regarded as a separate division of spore plants and called Equisetophyta, Arthrophyta, Calamophyta or Sphenophyta. When treated as a class, the names Equisetopsida s.s. and Sphenopsida have also been used. They are now recognized as rather close relatives of the ferns (Polypodiopsida) of which they form a specialized lineage. However, the division between the horsetails and the other ferns is so ancient that many botanists, especially paleobotanists, still regard this group as fundamentally separate at the higher level. Description The horsetails comprise photosynthesising, "segmented", hollow stems, sometimes filled with pith. At the ju ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iridopteridales
Iridopteridales is an order of the extinct cladoxylopsids. It contains the genus ''Ibyka'' which is a possible ancestor of the horsetails ''Equisetum'' (; horsetail, snake grass, puzzlegrass) is the only living genus in Equisetaceae, a family of ferns, which reproduce by spores rather than seeds. ''Equisetum'' is a " living fossil", the only living genus of the entire subclass ....Thomas N. Taylor, Edith L. Taylor, Michael Krings: Paleobotany. The Biology and Evolution of Fossil Plants . Second Edition, Academic Press 2009, , p. 398-400. References Fern orders Prehistoric plant orders {{paleobotany-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horsetails
''Equisetum'' (; horsetail, snake grass, puzzlegrass) is the only living genus in Equisetaceae, a family of ferns, which reproduce by spores rather than seeds. ''Equisetum'' is a " living fossil", the only living genus of the entire subclass Equisetidae, which for over 100 million years was much more diverse and dominated the understorey of late Paleozoic forests. Some equisetids were large trees reaching to tall. The genus '' Calamites'' of the family Calamitaceae, for example, is abundant in coal deposits from the Carboniferous period. The pattern of spacing of nodes in horsetails, wherein those toward the apex of the shoot are increasingly close together, is said to have inspired John Napier to invent logarithms. Modern horsetails first appeared during the Jurassic period. A superficially similar but entirely unrelated flowering plant genus, mare's tail ('' Hippuris''), is occasionally referred to as "horsetail", and adding to confusion, the name "mare's tail" is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
