Japanese name: ハグロソウ（葉黒草） Scientific name:Peristrophe japonica
[Overview]
A perennial 20–50 cm tall, found in the shade of lowland forests.
The stem is erect and sparsely branched.
The stem has short hairs and 4–5 faint ridges, and the nodes are swollen.
The leaves are simple and opposite, elliptic, 2–10 cm long and 1–2.5 cm wide, with entire margins.
Flower branches 0.5–1.5 cm long come out at the branch tips or from the upper leaf axils, bearing a pair of large bracts.
There are 2–3 flowers inside the bracts, but usually only one opens.
The flowers are pale pink and two-lipped, twisted 180 degrees so that top and bottom are reversed.
The apparent upper lip is shallowly 3-lobed, and the lower lip hangs down.
The fruit is a capsule.
