in Japan, Honshu, Kawaguchi lake, May 2008 (pictures 1, 2 & 3)
in Japan, Honshu, Mt. Rokko, May 2008 (pictures 4, 5 & 7)
in Japan, Awaji Island, May 2008 (picture 6)
in Japan, Shikoku, Omogo, May 2008 (picture 8)
in Japan, Honshu, Nikko, June 2010 (picture 9)

Description in Syst. Veg., ed. 15 bis [Roemer & Schultes] 3: 461 (1818)