Submerged star liver moss
Submerged star liver moss | ||||||||||||
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Submerged star liver moss ( Riccia fluitans ), submerged form |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Riccia fluitans | ||||||||||||
L. emend. Lorb. |
The submerged star liver moss ( Riccia fluitans ), also known as (flooding) pond liver moss , is a liverwort that floats or occurs submerged in the water . In autumn it sinks to the bottom of the water. New individuals develop from the enduring Thallusspitzen in spring. The dioecious liverwort is extremely rarely fruiting, so that reproduction takes place almost exclusively through sprouting . As a collective species ( Riccia fluitans agg. ) The taxon includes Riccia fluitans s. st. also Riccia rhenana Lorb. ex trash. Frib. This taxonomically controversial clan can only be delimited in terms of the land form and the number of chromosomes and is therefore often not considered separately from Riccia fluitans .
description
This liverwort does not form rhizoids (root felt). Its bearings (thalli) are light green, ribbon-shaped, irregularly forked several times and up to 4 cm long. The bearings of the floating form are narrow band-shaped and 1 to 1.2 mm wide. The land form is coarse, less forked and the thalli can be up to 2.8 mm wide - this value is only achieved by the taxon R. rhenana , while the terrestrial form of R. fluitans s. st. only has thalli up to 1.5 (1.8) mm wide. The ends of the thallus are rounded, somewhat widened, provided with one or two incisions and with underlying, transparent air chambers that have a network-like field ( aerenchyma ). Breathing openings are not uncommon. There are only a few colorless, crescent-shaped abdominal scales along the center line (compare, however, the swimming liver moss ).
The submerged star liver moss can survive dehydration for over six months ( poikilohydric ) and sprouts again after about one to two weeks after watering. A culture is even possible from younger herbarium material .
Distribution and location
The submerged star liver moss is widespread worldwide and mostly inhabits shallow, sunny to shady, meso- to weakly eutrophic, weakly acidic to lime-rich or base-rich and clean standing water or slow-flowing ditches. The swimming form floats under water (submerged) or just above the water surface. Less landforms grow on dry mud. Spongy, spherical cushions are sometimes formed when submerged. The species or group of species often occurs together with duckweed plants of the genera Lemna , Spirodela or Wolffia and is sometimes displaced by them when there is increased nutrient availability.
use
This moss is widely used in aquaristics - as a spawning substrate for fish and as an ornamental plant.
literature
- Ruprecht Düll: Excursion pocket book of the mosses . IDH-Verlag, Bad Münstereifel 1997, ISBN 3-925425-15-2
- Jan-Peter Frahm & Wolfgang Frey (with J. Döring): Moosflora . 4th edition, UTB 1250, Ulmer-Verlag, Stuttgart 2004, ISBN 3-8252-1250-5
- Martin Nebel & Georg Philippi (eds.): The Moose Baden-Württemberg. Volume 3 . Ulmer-Verlag, Stuttgart 2005, ISBN 3-8001-3278-8
- Volkmar Wirth , Ruprecht Düll: Color Atlas of Lichen and Moss. Ulmer, Stuttgart 2000, ISBN 3-8001-3517-5 .
Individual evidence
- ↑ Michael Sauer (arr.): Ricciaceae, Sternlebermoose. In: Martin Nebel & Georg Philippi (eds.): Die Moose Baden-Württembergs. Volume 3: Special Part (Bryophyta: Sphagnopsida, Marchantiophyta, Anthocerotophyta). Ulmer, Stuttgart 2005, p. 114 ff. ISBN 3-8001-3278-8
- ↑ Christel Kasselmann : aquarium plants. Ulmer Verlag, Stuttgart 1995; 2nd, revised and expanded edition 1999, ISBN 3-8001-7454-5 , p. 404.