Thalassiosira sp.

High resolution image of Thalassiosira sp. 2001 Photo courtesy of Brian Bill, Northwest Fisheries Science Center.

Thalassiosira is a common diatom in Washington waters and frequently occurs as part of the spring bloom which begins the new growing season for the phytoplankton. The cells are disc-shaped and are usually joined together in long chains by one or more organic threads. Organic threads sometimes also extend from small spines found around the margin of the cells and may help the cells stay afloat in the water.