Coprosmanthus simadae (Masamune) Masamune; Smilax herbacea Linnaeus var. intermedia C. H. Wright; S. herbacea var. nipponica (Miquel) Maximowicz; S. herbacea var. oblonga C. H. Wright; S. longipedunculata Merrill; S. nipponica subsp. manshurica Kitagawa; S. nipponica var. manshurica (Kitagawa) Kitagawa; S. oblonga (C. H. Wright) J. B. Norton; S. simadae Masamune.

Herbs annual, erect or sometimes slightly climbing. Stem simple, terete, 8--100 cm, smooth, hollow and slightly pithy. Petiole 1.5--4.5 cm, scarcely winged; abscission zone distal; tendrils sometimes present. Leaf blade ovate to oblong, 4--20 × 2--14 cm, abaxially glaucous and usually powdery-pubescent. Inflorescence of 1 umbel, basally not prophyllate; peduncle 3--9 cm, slightly compressed; umbels of both sexes 20--30-flowered, base thickened. Male flowers: tepals usually reflexed at anthesis, greenish yellow or white, ca. 4 × 1 mm; stamens 2.5--3.5 mm. Female flowers: tepals subequaling male ones; staminodes 6. Berries blue-black, globose, 6--7 mm in diam., white powdery. Fl. Apr--May, fr. Aug--Sep.

Forests, grassy slopes, moist places along streams; 200--1400 m. Anhui, Fujian, Guangdong, Guizhou, Henan, Hunan, Jiangxi, Liaoning, Shandong, Sichuan, Taiwan, ?Yunnan, Zhejiang [Japan, Korea].