矮小耳草 ai xiao er cao

Gonotheca ovatifolia (Cavanilles) Santapau & Wagh; Oldenlandia nudicaulis Roth; O. ovatifolia (Cavanilles) Candolle; Thecagonum ovatifolium (Cavanilles) Babu.

Herbs, erect, annual, to 15 cm tall; stems terete to 4-angled, often sulcate, densely villosulous, pilosulous, or puberulent with pubescence denser, longer, and apparently glandular on upper (i.e., distal) parts of internodes. Leaves subsessile to usually petiolate, distributed along stem or those at uppermost 2 nodes clustered or apparently 4-verticillate especially at base of inflorescence; petiole 1-5 mm, densely puberulent to villosulous; blade drying membranous, elliptic or ovate, 1-6 × 0.7-3 cm, adaxially glabrous, abaxially puberulent or villosulous to glabrescent, base cuneate to rounded, apex acute to rounded; secondary veins 3-6 pairs; stipules fused to petiole bases, truncate to broadly rounded, 1-2.5 mm, pilosulous to glabrescent, erose to glandular-lacerate and usually also with 1-3 linear lobes to 1 mm. Inflorescence terminal, cymose to paniculate, 3-10 cm, glabrous, several to many flowered, pedunculate; peduncles 1-3, 1.5-4 cm, slender; axes mostly dichotomous; bracts triangular, 0.1-0.5 mm; pedicels 1-12 mm. Flowers pedicellate. Calyx glabrous; hypanthium portion subglobose, ca. 0.5 mm; limb lobed essentially to base; lobes triangular, 0.2-0.3 mm. Corolla white, tubular or salverform, outside glabrous; tube 1-1.5 mm, barbate in throat; lobes lanceolate, ca. 1 mm. Anthers exserted, ca. 0.2 mm. Stigma ca. 0.6 mm, exserted. Fruit capsular, compressed globose, 2-3 × 2-3 mm, glabrous, loculicidally dehiscent across top through beak, beak broadly rounded, to 0.3 mm high; seeds numerous, smooth. Fl. and fr. Jul-Aug.

Broad-leaved forests or grasslands on mountain slopes, sometimes on limestone rocks. Guizhou, Hainan, Taiwan, Yunnan [India, Malaysia, Nepal, Pakistan, Philippines, Sri Lanka, Thailand].

The measurements of several structures, in particular calyx, corollas, and anthers, given by Dutta and Deb (Taxon. Rev. Hedyotis. 2004) and also W. C. Ko (in FRPS 71(1): 71-72. 1999) do not agree with the specimens studied, nor with Dutta and Deb’s own figure. The measurements in the description here are taken from specimens, which agree with Dutta and Deb’s figure. All authors have found both the anthers and stigmas exserted (cf. Dutta & Deb figure; Cooray 69011901R, MO!) except Fl. Bhutan (2(2): 762-763. 1999), who found the anthers included.