Plectonema
| Plectonema | ||||||||||||
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Plectonema , illustration |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Plectonema | ||||||||||||
| Thuret ex Gomont , 1892 |
Plectonema is a genus from the tribe of cyanobacteria (blue-green algae).
description
Plectonema forms improperly branched, mostly blue-green, single-row threads with a diameter of 0.7 to 22 µm. Like all bacteria, their cylindrical cells contain neither nuclei nor plastids . Each thread sits in a thin gelatinous sheath. The false branching is caused by intercalary growth, a loop is formed in the thread that breaks out of the gelatinous sheath, usually after a cell has died. The side branches created in this way each form new gelatinous sheaths.
Reproduction
The asexual reproduction is done by hormogonia, ie by capable of creeping thread fragments. Thread fragmentation is also possible.
Sexual reproduction is absent in all cyanobacteria.
distribution
Plectonema lives on aquatic plants and on stones in the bank zone of standing and flowing waters. Some species survive the occasional dry run of their waters.
Types (selection)
- Plectonema andinum
- Plectonema litorale
- Plectonema puteale
- Plectonema tomasinianum
- Plectonema volkensii
swell
- 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 .
