01 / Oyodokawagoromo Habitat
An endemic found only in the Iwase Riverwas described as new in 1999.
A waterweed of the Podostemaceae family, it is a seed plant yet looks like moss or algae. Its roots become flat thalli that spread over the rock surface. About 3.5km from just below the Old Iwase Bridge (旧岩瀬橋), with some sections excluded, is a national natural monument.
- National natural monument: 2016-03-01
- Confirmed in 1928, described as new in 1999
- Designated area: about 3.5km

