Portrait

Description:

Portrait of the colorless chrysophyte, Siphomonas fritschii (Pringsheim,1946). Cells occur singly or in pairs at the ends of hollow, sometimes forked tubes with their flagella protruding. These tubes are sometimes tinged various shades of brown due to manganese and iron salts. The cells are rounded posteriorly and slightly truncate anteriorly. Two unequal flagella arise from the edge of the anterior end. A small greenish stigma lies near the flagellar insertions. The contractile vacuole is seen posteriorly in the uppermost cell. The cells frequently flee their stalks to swim free. Collected from an ephemeral freshwater pool near Boise, Idaho November 2004. Previously reported only from England and France. A dense growth of bacteria is evident in this image. DIC.