Callitriche

Water star ( Callitriche ), 1 = C. hamulata, 2 = C. hermaphroditica

Water star ( Callitriche ) constitute a genus of angiosperms. Their position within the angiosperms was due to a lack of features, in particular because of the strongly reduced flowers, long unclear. Some of them were led into a mono- generic family Callitrichaceae. They are classified according to the findings of molecular biology in the family of the plantain family ( Plantaginaceae ). The genus name is derived from Greek Callitriche Wörten kallos for physical beauty and thrix, trichos for hair (because of the growth form ) from.

Description

Water stars are creeping living on the ground or partly or completely below the water surface, one to perennial herbaceous plants. The shoot axis grows thready and is busy with opposite, next leafless deciduous leaves. The shape and arrangement of the blades greatly varies depending on the location. Under the surface located plants which have or lanceolate leaves and long internodes linealische. Plants whose stem axis grows over the water, have shorter internodes, so that the then elliptical or spatulate leaves are in rosettes. Terrestrial growing plants have mostly ovate or almost circular leaves. In the axils of the stem axis are glandular scales, both shoot axis and leaves are covered with scale-like trichomes.

Water Star species are monoecious ( monoecious ) or dioecious ( dioecious ) getrenntgeschlechtig. The unisexual flowers are in the axils and are either used individually or in pairs with a male and a female flower before. A perianth is absent, two bracts are crescent-shaped pronounced or also missing. The male flowers usually consist of a single, rarely up to three stamen / stamens with a slender filament and a kidney-shaped anthers. In the female flowers two carpels are fused into a superior ovaries, which is divided by a false septum into four chambers. In each ovary chamber is a single anatrope ovule. The two free pens are thready.

The fruit is a gap fruit that splits into four one-seeded fruit part. The seeds have a fleshy endosperm.

Types and occurrence

The genus of the water star ( Callitriche ), comes with about 25 to 30 species worldwide before ( with the exception of South Africa ).

In Germany the following water star species were found:

  • Stielfrüchtiger Water Star ( Callitriche brutia Petagna, Syn: Callitriche pedunculata DC. )
  • Stump edged water star ( Callitriche cophocarpa Sendtner, Syn: Callitriche polymorpha Lönnr. )
  • Hook Water Star ( Callitriche hamulata Kütz ex WDJ Koch, Syn. Callitriche intermedia Hoffm. )
  • Autumn Water Star ( Callitriche hermaphroditica L., Syn: Callitriche autumnalis L., Callitriche virens Goldb. )
  • Nussfrüchtiger Water Star ( Callitriche obtusangula Le Gall )
  • Swamp Water Star ( Callitriche palustris L., Syn: Callitriche verna L., Callitriche vernalis WDJ Koch)
  • Flachfrüchtiger Water Star ( Callitriche platycarpa Kütz. )
  • Pond Water Star ( Callitriche stagnalis Scop. )

Other species in Europe are:

  • Callitriche lusitanica the Scotsman, which is found in Portugal, Spain and North Africa.
  • Callitriche pulchra the Scotsman, which is found on the island of Gavdos and in Libya.
  • Callitriche truncata cast. , Which occurs in southern and Western Europe.

These were introduced from North America and naturalized in France places:

  • Callitriche peploides Nutt.
  • Callitriche terrestris Rafin.

Swell

  • Description in the Western Australia Flora. (English )
  • Henriette Dorothea Schotsman: Callitriche L. In: TG Tutin, VH Heywood, NA Burges, DM Moore, DH Valentine, SM Walters, DA Webb ( eds.): Flora Europaea. Volume 3: Diapensiaceae to Myoporaceae, Cambridge University Press, Cambridge, 1972, ISBN 0 - 521-08489 -X, pp. 123-126 ( limited preview on Google Book Search ).
  • Inga Hedberg, Olov Hedberg: Callitrichaceae. In: H. J. Beentje: Flora of Tropical East Africa. Balkema, Lisse 2003 preview.
Asterids Ovary (botany)
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