| Family | Ranunculaceae |
| Subfamily | Ranunculoideae |
| Tribe | Anemoneae |
| Scientific name | Clematis williamsii A. Gray |
| Synonyms | Clematopsis williamsii (A.Gray) Tobe |
| Common name | (Japanese common name) shirobana-hanshodzuru (シロバナハンショウヅル or シロバナハンショウズル, 白花半鐘蔓 [meaning: white flowering alrm bells vine]) |
| (English common name) none | |
| Distribution | (Japan) Honshu (Pacific Ocean, west of Kanto region), Shikoku, Kyushu |
| (Other nations) none | |
| Habitat | Mountane foprest (mainly in limestome area) |
| Chromosomal number | unknown |
| Description | Leaves ternate, leaflets each 3-8cm long, 1-3.5cm wide. Flowers 4 white calyx lobes each 13-20mm long, flowering in April to June. Fruits ca. 4mm long. Vine. Shrub or subshrub. |
| May 2007 at Tsukuba Botanical Garden |
May 2007 at Tsukuba Botanical Garden |
May 2007 at Tsukuba Botanical Garden |
| April 2008 at Kochi Prefecture Makino Botanical Garden |
April 2008 at Kochi Prefecture Makino Botanical Garden |
April 2008 at Kochi Prefecture Makino Botanical Garden |