Ecological Risk Screening Summary - Mexican Mosquitofern (Azolla mexicana) - Uncertain Risk

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.

Mexican mosquitofern (Azolla mexicana) is a small floating aquatic fern native to much of western North and South America, including the western and mid-western United States. It may have been introduced occasionally in the eastern United States. This fern is a nitrogen fixer and as such has been used as a green manure in agriculture, particularly in rice production. The history of invasiveness is classified as Data Deficient. There were records of introduction found for Azolla mexicana, with some resulting in established populations in Europe and India. No records of any impacts from those introductions were found. The overall climate match is high. Azolla mexicana is native to the western portions of North America, including the western United States. Many areas east of the Mississippi and upper Plains States, which are not in the native range, still have a high climate match. The certainty of assessment is low due to a lack of information regarding the introductions and impacts from introductions. The uncertainty in the taxonomy of the Azolla genus further reduces the certainty of assessment. The overall risk assessment category is Uncertain.