Liverworts

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Liverworts
Fountain liver moss (Marchantia polymorpha)

Fountain liver moss ( Marchantia polymorpha )

Systematics
without rank: Chloroplastida
without rank: Charophyta
without rank: Phragmoplastophyta
without rank: Streptophyta
Empire : Plants (Plantae)
Department : Liverworts
Scientific name
Marchantiophyta
Stotler & Crand.-Stotl.

The liverworts (Marchantiophyta) are a division of plants and one of the three groups that are known as mosses .

features

The distinguishing features to the deciduous mosses (Bryophyta) are in the gametophyte :

  • The protonema is reduced and consists of only a few cells.
  • The rhizoids are unicellular.
  • The leafy liverworts have three rows of leaves. The ventral (below) lying row of leaves is smaller and mostly of a different shape and is called sub-leaves (amphigastria). It can also be absent.
  • The leaves have no rib.
  • The cell shape is parenchymatic, i.e. rather rounded, while the mosses often have elongated (prosenchymatic) cells.
  • The cells of the thallus or leaf often have oil bodies .
  • The antheridia and archegonia have no paraphyses .

The gametophyte is multifaceted: it can be thallous or leafy. The cells contain numerous chloroplasts .

The distinguishing features to the deciduous mosses in sporophytes are:

  • It's short-lived.
  • The spore capsule is differentiated before the capsule stalk ( seta ) extends.
  • The Seta has delicate walls.
  • In the capsule, all the spores ripen at the same time.
  • The wall of the spore capsule lacks the stomata .
  • The capsule opens with four slots and pops up in four flaps.
  • The capsule does not have a central column ( columella ).
  • In the spore capsule elaters formed.

Systematics

The liverworts used to be listed in only one class "Hepaticae". Molecular genetic studies led to the group being broken down more and more. Stech and Frey structure liverworts as follows:

For a breakdown down to the family level, see the moss system .

Surname

The name liverwort comes from the Middle Ages, when medicinal plants were selected according to the motto similia similibus curentur (similar heals similar) ( doctrine of signatures ). The liver-shaped thallus from Marchantia , for example , was used as an extract boiled in wine as a medicine against liver diseases. The term was then transferred to the whole group, including the foliage liverworts.

supporting documents

Individual evidence

  1. ↑ Wolfgang Frey, Eberhard Fischer, Michael Stech: Bryophytes and seedless Vascular Plants . In: Wolfgang Frey (Ed.): Syllabus of Plant Families - A. Engler's Syllabus of Plant Families . 13th edition. tape 3 . Borntraeger, Berlin / Stuttgart 2009, ISBN 978-3-443-01063-8 , pp. 20-22 .

Web links

Commons : Marchantiophyta  - collection of images, videos and audio files