
Zygnema

Zygnema is a genus of freshwater filamentous thalloid 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.
Species.
Some species include: