Zygnema

Zygnema
Zygnema, showing characteristic dual star-shaped chloroplasts. Numbered ticks are 20 µm apart.
Numbered ticks are 122 µm apart.
Scientific classification
Kingdom:	Plantae
Division:	Charophyta
Class:	Zygnematophyceae
Order:	Zygnematales
Family:	Zygnemataceae
Genus:	Zygnema C. Agardh, 1817
Synonyms
Globulina Link in Nees 1820 Lucernaria Roussel, 1806 Pleurodiscus Lagerheim, 1895 Rhynchonema Kützing, 1849 Stellulina Link, 1833 Thwaitesia Montagne, 1845 Tyndaridea Bory de Saint-Vincent 1822 ‘Tendaridea’ Bory de Saint-Vincent 1822 Tendaridella Gaillon, 1833

Zygnema is a genus of freshwater filamentous alga comprising about 100 species. A terrestrial species, Z. terrestre, is known from India. Zygnema grows as a free-floating mass of filaments, although young plants may be found anchored to streambeds with a holdfast. The filaments form a yellow-green to bright green colored tangled mat, and are composed of elongate barrel-shaped cells, each with two star-shaped (stellate) chloroplasts arrayed along the axis of the cell.

Some species include:

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