大叶钩藤 da ye gou teng

Large lianas, height not noted. Young stems weakly to markedly quadrangular, pilosulous, tomentulose, or glabrescent. Petiole 3-25 mm, glabrous to densely tomentulose; leaf blade drying thinly leathery and yellowish brown adaxially, ovate or broadly elliptic, 10-16 × 6-12 cm, adaxially glabrous except strigillose along veins, abaxially sparsely to densely hirsutulous with pubescence denser along veins, base rounded, subcordate, or cordate, apex acute or shortly acuminate; secondary veins 6-9 pairs, usually with pubescent domatia; stipules caducous, ovate, 6-12 × 6-15 mm, 2-lobed for 1/2 or 2/3, lobes triangular to ovate. Inflorescences axillary, tomentulose to glabrescent; peduncle 3-7 cm; bracts triangular, 6-8 mm; flowering heads solitary, 15-20 mm in diam. across calyces, 40-50 mm in diam. across corollas; bracteoles absent; pedicels 2-5 mm. Flowers pedicellate. Calyx densely strigillose; hypanthium portion obconic, 2-2.5 mm; limb deeply lobed; lobes linear-oblong, 3-4 mm, obtuse to rounded. Corolla pale green to white, salverform, outside strigillose to tomentulose; tube 9-10 mm; lobes oblong to ligulate, ca. 2 mm, obtuse to rounded. Fruiting head 8-10 cm in diam.; pedicels 6-18 mm. Fruit pedicellate, fusiform, 14-20 × 4-5 mm, densely strigillose; seeds 6-8 mm. Fl. Jul, Sep, Dec, fr. Mar-Apr, Sep-Nov.

On canopy crowns in secondary forests; 300-900 m. Guangdong, Guangxi, Hainan, Yunnan [Bangladesh, Bhutan, India, Laos, Myanmar, N Thailand, Vietnam].