Chloronema has unusually large cells, 2-5µm wide, and can be up to several hundred micrometers long.
Chloronema develop in freshwater lakes containing low levels of sulfide, occuring together with other species of
green sulfur or
purple sulfur bacteria.
Taken from the text Brock Biology of Microorganisms (10th ed.). Madigan, M.T., Martinko, J.M., and Parker, J. 2003. Prentice Hall. 440p.