Pleurosira
| Pleurosira | ||||||||||||
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| Scientific name | ||||||||||||
| Pleurosira | ||||||||||||
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Pleurosira is a genus of diatoms (Bacillariophyta) with only a few species that occur in freshwater and seawater.
features
Pleurosira is a centric diatom. It forms chains of very large cells. The individual cells have the typical diatoms shell consisting of two counters with very fine pores. The bowls are rectangular in the side view and elliptical in the bowl view. The cell is immobile. It contains a central cell nucleus that is suspended from visible plasma threads. The many lenticular plastids are wall-mounted and colored golden brown by fucoxanthin . The individual cells are connected to one another at their corners by gel cushions and therefore form zigzag chains.
Asexual reproduction occurs through the typical division of diatoms into two parts, which leads to the reduction of the cells. Sexual reproduction is unknown.
Occurrence
Pleurosira grows sitting on other algae. It occurs in warm rivers, which can also be salty. Pleurosira is originally not at home in Central Europe and has certainly only been able to settle here in special man-made locations , such as in the area of cooling water discharges or in rivers with higher salt concentrations.
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. 250.