Description from Flora of China
Archiclematis Tamura; Atragene Linnaeus.
Vines woody or herbaceous and perennial, rarely erect shrubs, subshrubs, or perennial herbs. Leaves opposite, rarely fascicled or alternate, simple or compound; leaf or leaflet blades palmately veined. Inflorescences cymose, sometimes solitary, usually pedunculate, 2-bracteate. Flowers bisexual or unisexual. Sepals 4 or 5(--8), petaloid, spreading, ascending, or erect, usually valvate in bud. Petals absent. Stamens numerous, sometimes outer ones sterile and becoming linear or petaloid staminodes; anthers introrse. Carpels numerous, usually pubescent or villous; ovaries 1-ovuled; ovule pendulous. Style elongated after anthesis, rarely slightly or not elongated. Achenes usually ± bilaterally compressed; persistent style usually strongly elongated, plumose.
In the protologue of Clematis zhejiangensis R. J. Wang (J. Trop. Subtrop. Bot. 7: 28. 1999), the author stated that his new species is related to C. quinquefoliolata . However, because the type specimen is in fruit, without flowers, the systematic position of this species is uncertain at present.
About 300 species: widespread throughout the world; 147 species (93 endemic) in China.
(Authors: Wang Wencai; Bruce Bartholomew)