Dig deeper at SERNEC, a consortium of southeastern herbaria.
Check out EDDMapS.org to see where this has been reported.
Spermatophytes (seed plants): Angiosperms (flowering plants): Monocots: Alismatales
Britton & Brown Illus Flora of Northeast US & adjacent Canada (Gleason, 1952)
Manual of the Southeastern Flora (Small, 1933)
Brazilian Waterweed, Brazilian Egeria, "Brazilian Elodea", "Anacharis"
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JK Marlow jkm160914_140
SE-EPPC Aquatic Plant ID Workshop
This is the "Elodea" or "Anacharis" of the aquarium trade, per Weakley's Flora.