波缘水竹叶 bo yuan shui zhu ye

Herbs perennial. Roots fibrous, to more than 5 cm × 1.5--4 mm, slightly fusiform thickened at middle, sparsely or densely tomentose. Rhizomes horizontal, elongate. Stems long creeping, ascending distally, to 50 cm, with infertile, short branches; internodes ca. 6 × 0.3--0.4 mm, subglabrous. Leaves sessile; leaf sheath ca. 1 cm, hirsute on 1 side; leaf blade ovate-lanceolate, ca. 12 × 3--3.5 cm, glabrous, margin undulate, apex shortly acuminate. Inflorescence terminal, corymbose, branched; cincinni lax, to 4 cm, glabrous; involucral bracts leaflike but much smaller than leaves; bracts lanceolate, apex acute; pedicels 1--1.3 cm, nearly straight. Sepals narrowly elliptic, 0.5--6 mm, persistent. Petals purple or black, obovate-orbicular. Fertile stamens 3; filaments pubescent; staminodes 3; antherodes 3-sect. Capsule ellipsoid, trigonous, ca. 7 mm. Seeds ca. 7 per valve, uniseriate, reticulate-pitted, pits white. Fr. May.

* SE Yunnan (Hekou Yao Zu Zizhixian).

Murdannia undulata differs from M. japonica in its creeping stems and elongate capsule; from M. hookeri in its much wider, undulate leaves and corymbose inflorescences far exceeding the leaves; and from both species in having more seeds per valve.