凹籽远志 ao zi yuan zhi

Heterosamara umbonata (Craib) Paiva.

Herbs annual, erect, (10-)15-20 cm tall. Stems terete, longitudinally angular, glabrous, branching apically; branchlets spreading, slender. Petiole ca. 1 cm; leaf blade abaxially glaucescent, adaxially green, ovate or elliptic to elliptic-lanceolate, 3-4 × 1.5-2 cm, papery, abaxially glabrous, adaxially sparsely white setose or along margin densely minutely setose, midvein raised abaxially, impressed adaxially, lateral veins 5 or 6 pairs, anastomosing near margin, base cuneate, decurrent, apex acuminate. Racemes terminal or axillary, 1-4 cm. Pedicel 0.5-1 mm, slender; bracts 3, caducous, subulate, unequal. Sepals 5, caducous; outer sepals 3, ovate, ca. 1.5 mm; inner sepals 2, petaloid, elliptic, 3-3.5 mm, base unguiculate, apex rounded. Petals 3, connate in lower 1/2, yellow; lateral petals rectangular-oblong, longer than keel; keel with apex broadly retuse, with appendage of 2 lobes each with 2 points. Stamens 8; filaments lower 2/3 united, forming an open staminal sheath; anthers ovoid. Ovary ellipsoidal, ca. 1 mm, ca. 0.5 mm in diam.; style broadening from base toward apex but then narrowing at apex, curved, apex obliquely funnelform. Capsule suborbicular, ca. 3 mm in diam., winged. Seeds black, elliptic, ca. 1.2 mm, ca. 1 mm in diam., tuberculate, sparsely white pilose, strophiole 2-lobed, decurrent, other end of seed with oblong slightly curved shiny black appendage ca. 2/3 as long as seed. Fl. and fr. Oct-Nov.

Forests, moist lands in valleys; ca. 1200 m. S Yunnan (Menghai) [Myanmar, Thailand].