生活型

herb

形態特徵

• Perennial herbs, stems 10–60 cm long, sparsely pilose or glabrate, aerial branches 5–20 cm tall.
• Leaves sessile, glabrous; emergent leaves 5–8-verticillate, oblanceolate to elliptic, 8–20 mm long, apex obtuse to rounded, base semiamplexicaul, margins lobed to variously parted, ultimate segments linear; submerged leaves 6–10-verticillate, obovate, widely obovate to widely elliptic, 5–40 mm long, finely divided, segments opposite, flattened, 0.8–1 mm wide.
• Flowers solitary, axillary, sessile or subsessile. Calyx 4–7 mm long, cleft to below middle, pubescent, bracteoles mostly absent; lobes 2–3.5 mm long. Corolla tubular, blue, violet or purple, 5–8 mm long, villose on lateral surface inside; lobes ca. 1 mm long, white. Cleistogamous flowers smaller.
• Capsule ellipsoid, 3.5–5.5 mm long, ca. 3 mm across.

分布

• 台灣 : ponds and ditches in the north and northeast of the island.
• 世界 : East Asia.

引證標本

ILAN: Suao, Suzuki s. n. 1931.

參考文獻

• LIU, Ho-Yih, Flora of Taiwan, second edition 4: 602. 1998.  (Fl. Taiwan 2nd edit.)