Actinidia L. (1753), in the family Actinidiaceae, contains 40 species.
Description Woody climbers to 20m or more, with twining stems. The leaves are alternate, deciduous, sometimes bristly-hairy, sometimes marked with patches of silver or pink. The flowers are unisexual, produced in the leaf axils, solitary or clustered, the males and females usually on separate plants, and often well scented. Sepals 5, petals 5 and white, reddish, or yellowish. Stamens numerous. Ovary superior, with 3–30 fused carpels and numerous styles. Pollination is by insects. The fruits are fleshy, juicy berries with numerous small, black seeds.
Key Recognition Features Climbers with white male or female flowers with numerous styles and stamens, and large, juicy, greenish berries with numerous small seeds.
Evolution and Relationships In many systems of classification, Actinidiaceae is associated with Eucryphiaceae. In the system followed here, Eucryphiaceae is put close to the Rosaceae, and Actinidiaceae is considered close to Ericaceae, but the seeds suggest affinities also with Theaceae. Clematoclethra is a related genus with 1 species, C. scandens (Franch.) Maxim. in China; it has flowers with 10 stamens, 1 style, and 5 fused carpels in the ovary.
Ecology and Geography In woods and scrub, climbing into large trees, in China and Japan southwards to Indonesia.
Comment The species with variegated leaves are attractive ornamentals, and there have been reports that male plants develop better-coloured leaves. Actinidia deliciosa (Chev.) Liang & Ferguson is the current name for the edible kiwi fruit or Chinese gooseberry, formerly but erroneously called A. chinensis Planch. Other species, such as A. arguta (Sieb. & Zucc.) Miq., have smaller edible fruit.