49. Euphorbia monocyathium Prokhanov, Izv. Glavn. Bot. Sada S.S.S.R. 29: 552. 1930.
单伞大戟 dan san da ji
Herbs, perennial, ascending or prostrate, 6-15 cm tall. Rootstock vertical, cylindric, to 8 mm thick, apex with dense cluster of old and new stems. Stems unbranched, ca. 2 mm thick, light red or reddish, glabrous. Leaves alternate, mostly uniform in size; stipules absent; basal scale-leaves ovate, overlapping; petiole absent; leaf blade elliptic or ovate-elliptic, 1-2.5 × 0.4-0.9(-1.2) cm, glabrous, base subrounded, margin entire, apex acuminate. Inflorescence reduced to a solitary terminal cyathium; primary involucral leaves 3-5, similar to normal leaves, 0.7-2 × 0.4-1.5 cm, primary rays not developed [cyathophylls 2, similar to normal leaves, but smaller, 7-11 × 2-7 mm]. Cyathium stipe to 2 mm; involucre broadly campanulate, ca. 3 × 3-4 mm, glabrous outside, lobes ovate, relatively large, pubescent at margin and inside; glands 4, pale brown, rounded-reniform. Male flowers many, not exserted from involucre. Female flower: ovary exserted from cup, smooth, glabrous; styles connate below middle; style arms 2-lobed. Capsule ovoid (immature), 6-7 mm, smooth, glabrous. Seeds not seen. Fl. and fr. Jul-Sep.
Slopes, riverbanks. Xinjiang (Kashi) [Kazakhstan, Kyrgyzstan, Tajikistan].