Volume 16 (2016) Issue 2 Pages 203-206
Najas guadalupensis (Sprengel) Magnus subsp. floridana (R. R. Haynes et W. A. Wentz) R. R. Haynes et C. B. Hellquist (Hydrocharitaceae) was recorded from a brackish pond in Ehime Prefecture, Shikoku, as the second locality of the species in Japan. A specimens of the species was proved to have been collected in 1923 from the same area. The origin of the species in Japan was discussed.