Origin
First identified in North America. It is not known if it was introduced artificially.

Appearance
Prymnesium parvum is a species of microscopic flagellated algae. They are single-celled organisms and are ellipsoid or oval in shape. Each P. parvum cell has two flagella (tails used to move) which are the same size and one short peg-like appendage called a haptonema (unsure of its use). Each cell has two yellow-green to olive-colored chloroplasts which is what gives it the ’golden’ color.

Ecological Threat
P. parvum is of concern because of its ability to produce prymnesin which is a type of toxin which can cause large fish kills.
 

Maps

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Invasive Listing Sources

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• Maryland Invasive Species Council - Invasive Species of Concern in Maryland
• Mid-Atlantic Field Guide to Aquatic Invasive Species
• Pennsylvania's Field Guide to Aquatic Invasive Species
• West Virginia Invasive Species Strategic Plan and Volunteer Guidelines 2014
• Wisconsin's Invasive species rule – NR 40

References

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Common Name Reference: USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA, USA.

Scientific Name Reference: USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA, USA.