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Image of Mesodinium rubrum by Teri King, WSG Image of Mesodinium rubrum by Teri King, WSG
Both images: Mesodinium rubrum
Photo credit: Teri King, WSG

Phytoplankton of the month — December 2019

Mesodinium rubrum

Mesodinium rubrum is a marine photosynthetic ciliate that can resemble a sunflower. Its body is almost circular shaped, ranging from 100μm long and 7μm thick. Around the body are cilia that can stretch out to be 10-20 times longer than its body when in use. At high concentrations, Mesodinium rubrum can cause a bold red water discoloration.

SoundToxins, a diverse partnership of Washington state shellfish and finfish growers, environmental learning centers, Native tribes, and Puget Sound volunteers, is a monitoring program designed to provide early warning of harmful algal bloom events in order to minimize both human health risks and economic losses to Puget Sound fisheries.

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