16. Thesium psilotoides Hance, J. Bot. 6: 48. 1868.
白云百蕊草 bai yun bai rui cao
Herbs dwarf; rhizomes short, woody. Stems erect, branched at middle (branches rebranched), slender, 15-25 cm. Leaves sessile, scale-like, 1-1.5 mm, decurrent along stems to form ridges, 1-veined. Inflorescences cymose, fasciculate, 1-3-flowered; bracts scale-like, ca. 1.5 mm; bracteoles 4, scale-like, shorter than perianth, bracts and bracteoles forming an involucre around base of perianth. Perianth 5-merous, slightly dirty yellow, broadly campanulate, ca. 1.5 mm, tube divided to middle, ca. 1 mm, lobes triangular, margin inflexed. Stamens 5, on basal 1/3 of lobes; filaments short. Ovary sessile. Style erect, slightly shorter than stamens; stigma ± globose. Nutlet ovoid, ca. 2 × 2 mm, with ridges and inconspicuous reticulate veins, gradually narrowed to base; persistent perianth arched, adnate, slightly umbulate, short. Fl. May, fr. Aug.
Open grasslands under Pinus forests; 200-1300 m. Guangdong, [Cambodia, Indonesia, Philippines, Thailand].