20. Piper semiimmersum C. de Candolle, Notizbl. Bot. Gart. Berlin-Dahlem. 6: 479. 1917.
缘毛胡椒 yuan mao hu jiao
Climbers dioecious. Stems pale brownish when dry, thickly furrowed, usually densely hispid, less often glabrous. Petiole 0.8-1.3 cm, sparsely long pubescent; leaf blade oblong-ovate or ovate-lanceolate, rarely those toward apex of stem oblong, 11-18 × 2.5-7.5 cm, papery, often ± bullate when older, finely glandular, usually abaxially hispidulous along veins, adaxially glabrous or rarely sparsely pubescent at base, base obliquely cordate, basal lobes divergent or overlapping, bilateral difference 2-3 mm, apex shortly acuminate; veins 7, apical pair arising 1-2(-2.7) cm above base, usually alternate, reaching leaf apex, others basal; reticulate veins conspicuous. Spikes leaf-opposed. Male spikes 7-8 cm × ca. 2.5 mm; peduncle 2-2.5 cm, sparsely pubescent; bracts suborbicular, ca. 1.2 mm wide, peltate, margin pale brown, abaxially finely papillate pubescent, densely ciliate, ± sessile, base slightly tapered. Stamens usually 2; anthers reniform, very short. Female spikes 6-7 cm × 7-8 mm in fruit; peduncle 3-4 cm; rachis roughly pubescent; bracts as in male spikes but compressed and partly revolute, falcate or 3-pointed. Ovary partly immersed in rachis; stigmas 3 or 4, linear, small. Drupe globose, ca. 3 mm in diam., apex umbonate. Fl. Jan-May.
Wet places of valley forests, near villages; 200-900 m. W Guangxi, SW Guizhou, SE to SW Yunnan [N Vietnam]