Tree ferns

from Wikipedia, the free encyclopedia
Tree ferns
Tree fern with leaf fronds before and after unfolding

Tree fern with leaf fronds before and after unfolding

Systematics
without rank: Streptophyta
Empire : Plants (Plantae)
Department : Vascular plants (tracheophyta)
Ferns
Class : True ferns (Polypodiopsida)
Order : Tree ferns
Scientific name
Cyatheales
AB Frank

The tree ferns (Cyatheales) are an order of the ferns .

Not all species within this order form distinct stems. In addition, not all tree-shaped ferns belong to this order. In addition to the ferns in this order, the royal fern family (Osmundaceae) and rib fern family (Blechnaceae) contain some fern species with trunks in the genera Blechnum , Leptopteris , Sadleria and Todea . Fossil tree ferns of the genus Psaronius from the Marattiaceae family are known from the Carboniferous .

Tree ferns of the order Cyatheales first appeared in the Jura .

description

Sori on the underside of the leaf of Dicksonia antarctica

The order has no prominent common features.

Some species have a trunk-shaped growth, others have a creeping rhizome . Some have hairy stems, others have scales. The sori sit abaxially (on the underside of the leaf) or marginally (on the leaf margin). They may or may not be covered by an indusium .

The fronds of tree ferns are often more than 1 meter long in fully grown specimens, and almost always have one or more pinnatees. However, one species has simple, featherless fronds.

Unlike seed plants , tree ferns do not show any growth in the trunk. The trunk is supported by the root bundles that form as it grows.

The prothallium is green and heart-shaped.

Occurrence

Tree ferns grow in tropical and subtropical areas of the world. Some species also tolerate the temperate climates of rainforests in Australia , Tasmania and New Zealand and neighboring areas ( Malaysia , Lord Howe Island ). In general, tree ferns do not tolerate prolonged drought, and only a few species (for example Dicksonia antarctica ) survive mild periods of frost.

New species are regularly discovered in studies in previously unexplored areas of New Guinea . At the same time, some species are endangered or extinct due to collection for the ornamental plant trade, intensive logging and loss of habitat .

Economic importance

Tree ferns in the park of Arundel Castle , England

Tree ferns have been imported to England as ornamental plants since the 19th century, where they became popular plants in tropical houses. In many other areas of the world with only slight frosts, for example in southern England with its maritime climate (influenced by the Gulf Stream ), planting in landscape parks and gardens is possible.

Ornamental plants of commercial importance are found in the genera Cyathea and Dicksonia . Some species of tree fern can also be cared for in very bright rooms that are cool in winter or in winter gardens.

On the trunk and on the fronds of older specimens there are long silky hairs, which were used in China to stop bleeding and in Hawaii as a pillow filling.

Systematics

The order Cyatheales is in all likelihood a monophyletic group. According to Smith et al. (2006) divided into eight families:

  • Thyrsopteridaceae family
    • Thyrsopteris Kunze , with only one species:
  • Loxsomataceae family
  • Family Culcitaceae :
    • Culcita C. Presl , with only two types.
  • Plagiogyriaceae family
    • Plagiogyria (Kunze) Mett. , with about 12–37 species in East Asia and America
  • Cibotiaceae family
    • Cibotium Kaulf. , with about 7–12 species in tropical Asia, Polynesia and America
  • Family Cyatheaceae (including Alsophilaceae, Hymenophyllopsidaceae)
    • Alsophila R. Br. (Including Nephelea R.M. Tryon ), with at least 63 species
    • Cyathea Sm. , With at least about 300 species (including Cnemidaria C. Presl , Hemitelia R. Br. , Trichipteris C. Presl )
    • Gymnosphaera flower , with about 21 species
    • Hymenophyllopsis Goebel , with seven species in northern South America
    • Sphaeropteris Bernh. (including Fourniera J.Bommer ), with at least 13 species
  • Family Dicksoniaceae (including Lophosoriaceae )
    • Calochlaena (Maxon) MD Turner & RA White , with five species.
    • Dicksonia L'Hérit. , with about 7–25 species
    • Lophosoria C. Presl , with only one species in tropical America:
  • Metaxyaceae family
    • Metaxya C. Presl , with 6 species in tropical South America

photos

literature

  • Alan R. Smith, Kathleen M. Pryer, Eric Schuettpelz, Petra Korall, Harald Schneider, Paul G. Wolf: A classification for extant ferns. In: Taxon. Volume 55, No. 3, 2006, ISSN  0040-0262 , pp. 705-731, abstract, PDF file .
  • Mark F. Large, John E. Braggins: Tree Ferns. Timber Press, Portland OR et al. 2004, ISBN 0-88192-630-2 .
  • David John Mabberley: The Plant Book. A portable dictionary of the higher plants. Cambridge University Press, Cambridge et al. 1987, ISBN 0-521-34060-8 .

Web links

Commons : Tree Ferns (Cyatheales)  - Collection of images, videos and audio files
Wiktionary: Tree ferns  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. Peter H. Raven, Ray F. Evert, Susan E. Eichhorn: Biology of plants . 4th edition. de Gruyter, Berlin, New York 2006, ISBN 978-3-11-018531-7 , pp. 445 .
  2. Compact Lexicon of Biology: Cyatheales. Spektrum Akademischer Verlag, Heidelberg, 2001, accessed on October 19, 2014 .