Species that are considered uncertain risk need a more in-depth assessment beyond the Risk Summary to better define the species’ risk to U.S. environments.
Nitellopsis obtusa, Starry Stonewort, is an aquatic plant species native to Eurasia, from the west coast of Europe to Japan. This species has been introduced to the Great Lakes region of the United States and Canada, where it has become established. It has since spread to the Northeast and Midwest. Multiple negative potential impacts of introduction have been reported including forming dense mats of vegetation that completely cover the lake bottom, impacting the habitat used by native fish for spawning, negatively affects water quality for other macrophyte and phytoplankton, and decreasing native plant species richness and biomass. No information on this species in trade was available. Nitellopsis obtusa is found on multiple State invasive species invasive species
An invasive species is any plant or animal that has spread or been introduced into a new area where they are, or could, cause harm to the environment, economy, or human, animal, or plant health. Their unwelcome presence can destroy ecosystems and cost millions of dollars.
Learn more about invasive species lists. The history of invasiveness is Data Deficient. The overall climate match category for N. obtusa is High, with the areas of highest match being found in the Great Lakes region where the species has been introduced, as well as in the Northeast and Midwest in areas with and without known populations. The certainty of assessment is Low due to limited available information on actual impacts of introduction. The overall risk assessment category for Nitellopsis obtusa is Uncertain.
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Uncertain Risk
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