Zygnema

Zygnema
	Zygnema sp.
Systematics
without rank:	Chloroplastida
without rank:	Charophyta
Class :	Ornamental algae (Zygnemophyceae)
Order :	Yoke algae (Zygnematales)
Family :	Zygnemataceae
Genre :	Zygnema
Scientific name
	Zygnema
	C. Agardh 1817

Zygnema (thread algae, star algae) is a genus of green algae . It belongs to the Zygnemataceae family. Like Spirogyra , Zygnema often occursin spring in calm waters as free-floating, thread-like, light green "cotton wool".

It is one of the yoke algae (multiplication through yoke formation) and has no flagellated stages. Each cell contains two large star-shaped chloroplasts .

A special ability of the Zygnemataceae is to be able to use the ionic hydrogen carbonate for photosynthesis when there is a shortage of dissolved carbon dioxide . In doing so, they give off hydroxide ions , so that the pH value of the water in the vicinity of the algae floss can rise to values of up to 11.

species

There are at least 50 species in Central Europe. For example:

Zygnema stellinum
Zygnema commune
Zygnema leiospermum
Zygnema pectinatum
Zygnema sterile
Zygnema ericetorum

Web links

Commons : Zygnema - collection of images, videos and audio files

A detailed description in English from the Algaebase

literature

Christian van den Hoek, Hans M. Jahns, David G. Mann: Algae . 3. Edition. Thieme, Stuttgart 1993, ISBN 3-13-551103-0

Individual evidence

^ Christian van den Hoek, Hans M. Jahns, David G. Mann: Algen . 3. Edition. ISBN 3-13-551103-0 .
↑ Heinz Streble, Dieter Krauter: Life in the water drop . In: Komos Verlag (Hrsg.): Kosmos Naturführer . 13th edition. Komos, ISBN 978-3-440-15694-0 , pp. 186 .

[1] Christian van den Hoek, Hans M. Jahns, David G. Mann: Algen . 3. Edition. ISBN 3-13-551103-0 .

[2] Heinz Streble, Dieter Krauter: Life in the water drop . In: Komos Verlag (Hrsg.): Kosmos Naturführer . 13th edition. Komos, ISBN 978-3-440-15694-0 , pp. 186 .