Synura
Synura is one of only 3 synurophyte genera found in North America. The genus has quite a few species and is often abundant in freshwaters. Synura and other synurophytes are found in the plankton of freshwater lakes, ponds, and slow moving rivers or streams. Like other microscopic algae, synurophytes are an important food source for higher trophic levels. The group is found in temperate, subtropical, and tropical environments, but are much less abundant and diverse in arctic and subarctic habitats.
Synura sometimes forms blooms, and Synura petersenii especially is known to release ketones and aldehydes from the cells that can give the water an unpleasant fish-like odor or taste.   Unlike the diatoms, synurophytes can survive without their protective scales if silica is unavailable. Under experimental conditions it has been shown that naked Synura cells can regrow their scales within 24 hours with a sufficient supply of silica.   Like the siliceous remains of diatom cells, the siliceous scales of Synura and other scaled chrysophytes persist in the environment and remain intact within sediments after the cell has died. These preserved scales provide an important tool that helps ecologists to reconstruct environmental changes over time or to better understand the ecology of a particular system.   Synura sometimes migrates to deep waters at night both to avoid predators and to take advantage of available nutrients. During the day the cells remain closer to the well-lit surface waters.