Botryococcus braunii (Chlorophyta, Chlorococcales) is a colonial chlorophyte, made of ovoid cells that are closely packed to form golden brown mucilaginous lumps. Older cells usually have large amounts of reserve food material (oil) such that the cell contents are obscured, and the colonies float. The species is abundant at times, forming surface scums at lee shores. On a single occasion in January 2000 a bloom of this species covered the entire lake for several days, giving it a golden color, then disappeared abruptly. This photo shows Botryococcus braunii colonies at x200 mag, with their typical mucilaginous strands connecting colonies and enveloping them.