Nymphoides humboldtiana (Menyanthaceae) in Florida (U.S.A.) verified by DNA data

Certain Nymphoides populations in Florida, U.S.A., previously identified as the non-native N. indica (L.) Kuntze, are actually N. humboldtiana (Kunth) Kuntze, as verified using nuclear and plastid DNA data. These new records of N. humboldtiana in Florida are the only known localities in the U.S.A. outside of Uvalde County, Texas. Nymphoides humboldtiana is native to Texas, México, the Caribbean, and Central and South America. The newly identified Florida populations found near the city of Tampa in Manatee County (Ward Lake and Braden River) and Fort Walton Beach in Okaloosa County (Bass Lake) are presumed to be native. Nymphoides humboldtiana and N. indica share many superficial similarities, most notably white petals with ciliate hairs. Our findings suggest that certain morphologically-determined populations of N. indica in the U.S.A. may be incorrectly identified. Such populations might be re-examined using DNA methods to avoid any management actions against N. humboldtiana