生活型

herb

形態特徵

• Annual glabrous herbs, stems ascending, to 25 cm tall, much-branched near base.
• Leaves sessile or subsessile, ovate-trullate to lanceolate, 5–18 mm long, 2–6 mm wide, palmately 3–5-nerved, apex acute to obtuse, base rounded to truncate, margins subentire, glabrous.
• Flowers solitary, axillary; upper ones in more or less terminal leafy racemes; pedicel longer than subtending leaves, 10–20 mm long. Calyx cleft to near base, ca. 3 mm long, lobes linear, puberulent. Corolla white or very pale purple, ca. 6 mm long. Stamens 4; anterior pair staminodes, linear, apex clavate, posterior pair fertile, included.
• Capsule ellipsoid, + equaling or slightly longer than the persistent calyx, 2.5–3 mm long.

分布

• 台灣 : naturalized in shallow water ponds in the north.
• 世界 : Native to North America.

引證標本

TAOYUAN: Pushin, Kao 10746.

參考文獻

• LIU, Ho-Yih. 1998. Flora of Taiwan, second edition 4: 603. (Fl. Taiwan 2nd edit.)