Aeschynomene indica (Indian jointvetch, "Kusanemu")

Japanese name: クサネム （草合歓）
Scientific name: Aeschynomene indica

[Overview]
An annual 50–100 cm tall, found in wet places such as rice paddies and riverbanks.
Leaves are alternate and pinnately compound with an indistinct terminal leaflet, with 40–60 leaflets.
The leaflets are not opposite, narrowly oblong-elliptic, 10–15 mm long and 2–3.5 mm wide.
Pale yellow butterfly-shaped flowers are borne in pseudoracemes arising from the leaf axils.
The fruit is a broadly linear pod, 30–50 mm long and 5–6 mm wide, which breaks into 4–8 small segments.
The seeds are nearly ovate and ripen black.

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