Lemanea
| Lemanea | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
_(20418267875).jpg)
Lemanea fluviatilis , illustration (left side) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Lemanea | ||||||||||||
| Bory de Saint-Vincent |
Lemanea is a species of red algae (Rhodophyta) that occursin freshwater. It consists of around 15 species. One representative found in Central Europe is the bristle red alga ( Lemanea fluviatilis ).
features
The gametophytes are bristle-shaped and little or no branched algae from 10 to 25 cm in length. Their diameter is around two millimeters. They are knotty thickened at regular intervals. In the longitudinal section, a complex hollow cylinder can be seen, inside of which a central thread runs. Four side branches extend from the ends of the central thread. These branch out abundantly and form the jacket of the hollow cylinder. The cells contain a few disc-shaped, wall-mounted plastids . These are olive to blue-green, but never pure green.
The individual species differ according to their size, degree of branching, the presence of cortical cells around the central thread, their coloring and gender distribution.
Asexual reproduction is not known of this genus. The sexual reproduction of the genus corresponds to the complex generation change of the red algae with gametophyte, carposporophyte and a morphologically strongly deviating sporophyte , the so-called Chantransia phase. After the reduction division, gametophytes are again formed from cells of the Chantransia phase.
Occurrence
The representatives of the genus are relatively rare and occur in oxygen-rich, fast-flowing, cool streams and rivers mainly in the low mountain range. Other locations are in the splash zone of weirs and stones. They also occur above the waterline.
supporting documents
- Karl-Heinz Linne von Berg, Michael Melkonian u. a .: The Kosmos algae guide. The most important freshwater algae under the microscope. Kosmos, Stuttgart 2004, ISBN 3-440-09719-6 , p. 288.
- MD Guiry & GM Guiry: Lemanea . AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. Retrieved August 30, 2017.
