Marchantiaceae

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Marchantiaceae
Fountain liver moss

Fountain liver moss

Systematics
Empire : Plants (Plantae)
Department : Liverworts (Marchantiophyta)
Class : Marchantiopsida
Subclass : Marchantiidae
Order : Marchantiales
Family : Marchantiaceae
Scientific name
Marchantiaceae
Brid.

The Marchantiaceae are a family of liverworts from the order of the Marchantiales with almost 40 species.

features

The structure of the thallus is similar to that of a bifacial leaf . There is an upper, covering cell layer with respiratory pores, including air cavities, an assimilation parenchyma, a lower cell layer which is covered with rhizoids , often also with ventral scales. Both structures serve to absorb water. The respiratory pores are used for gas exchange between the thallus and the atmosphere. They can be designed as simple openings or represent a barrel-shaped structure. If the cells lose turgor due to water loss, the barrel collapses and closes the opening, thus reducing further water loss (cf. stomata of vascular plants).

Vegetative propagation is known from some representatives . Marchantia forms round breeding cups on the top of the thallus. The brood bodies are formed in the cups and washed out by the rain.

The sex organs are usually formed separately from the sexes on umbrella-shaped structures ( gametangiophores ), the height of which ranges from sitting to 10 cm. The antheridia are formed sunk on the top of disc-shaped antheridiophores, the archegonia on the underside of the umbrella-shaped archegoniophores. For fertilization it is necessary that the spermatozoids are transported by rain from the antheridiophores to the archegoniophores.

The sporogon is practically sessile and very small. In Marchantia it sits on the underside of the archegoniophore and opens with longitudinal fissures.

  • Formation of the brood bodies

  • Antheridia stand

  • female gametophyte and sporophyte

  • Thallus in plan and cross-section

Systematics

The Marchantiaceae family comprises the following genera with a total of almost 40 species:

literature

  • Jan-Peter Frahm: Biology of Mosses . Spectrum Academic Publishing House, Heidelberg and Berlin 2001, ISBN 3-8274-0164-X
  • Jan-Peter Frahm, Wolfgang Frey, J. Döring: Moosflora . 4th, revised and expanded edition (UTB for Science, Volume 1250). Ulmer, Stuttgart 2004, ISBN 3-8001-2772-5 (Ulmer) & ISBN 3-8252-1250-5 (UTB)

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. 31-32 .

Web links

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