| Family | Caryophyllaceae |
| Subfamily | Alsinoideae |
| Tribe | Alsineae |
| Scientific name | Pseudostellaria heterantha (Maximovicz) Pax var. linearifolia (Takeda) Nemoto |
| Synonyms | none |
| Common name | (Japanese common name) hina-wachigai-sou (ヒナワチガイソウ, 雛輪違草 [tiny wachigai weed (wachigai = unknown flowers name)]) |
| (English common name) none | |
| Distribution | (Japan) Honshu (Mt. Tsukuba, Mt. Fujiwara-dale in Mie Prefecture) |
| (Other nations) unknown | |
| Habitat | Mountane (subalpine) forest edge |
| Chromosomal number | unknown |
| Description | Plants 10-15cm tall. Leaves 2-5cm long. Flowers white ca. 1cm across, flowering in April. Perennial plants. |
| Note | Rare species |
| May 2006 at Mt. Tsukuba |
May 2006 at Mt. Tsukuba |
May 2006 at Mt. Tsukuba |
| May 2006 at Mt. Tsukuba |
May 2006 at Mt. Tsukuba |
May 2006 at Mt. Tsukuba |