Light microscope footage of Synura sp. algae colonies. Synura (from the Greek Syn , together and oura , tail) is a colonial alga formed by variable numbers of cells. The cells are held together by their posterior ends, forming a spherical colony. The cell membrane is covered with overlapping silica scales with spines on anterior scales. The cells contain two golden-brown plastids. Fossil scales similar to those of modern Synura cells have been found in middle Eocene deposits (about 47 million years of age) indicating that the synurophyceans are at least that old. Microscopic contrast method used: differential interference contrast. Captured field width: 0.4 mm. Sample taken from an algae culture of the culture collection of algae at the University of Cologne, CCAC.