Mexican mosquitofern is a tiny floating aquatic fern that is found in stillwater areas of lakes, oxbows and ponds. In the US, it is found in AR, AZ, CA, CO, IA, IL, KS, MN, MO, NE, NM, NV, OK, OR, TX, UT, WA, WI (USDA 2010
). In Canada, this species is found only in British Columbia where it is reported from the Shuswap, Sicamous, Salmon Arm, Little Fort, and Vernon areas It was first collected in BC by John Macoun from Sicamous in 1889, and was then reported by him from Salmon Arm in 1890 (COSEWIC 2008
Today, ten populations of this species are known in British Columbia, where it occurs in quiet pools in creeks, oxbow ponds, sheltered lake edges and small bays, and wet depressions. Mexican mosquitofern is easily spotted from a distance in mid- to late summer when plants turn a bright red on wetland surfaces. It may occur in small floating patches, or extensively cover the water surfaces.