Description from Flora of China
Trochostigma rufum Siebold & Zuccarini, Abh. Math.-Phys. Cl. Königl. Bayer. Akad. Wiss. 3(2): 727. 1843 ["rufa"]; Actinidia arguta (Siebold & Zuccarini) Planchon ex Miquel var. rufa (Siebold & Zuccarini) Maximowicz; A. callosa Lindley var. rufa (Siebold & Zuccarini) Makino.
Climbing shrubs, large, deciduous. Floral branchlets reddish, brownish puberulent; branches glabrous, lenticels small, conspicuous; pith brown, small, lamellate. Petiole 2-4 cm, slightly pubescent, glabrous when mature; leaf blade ovate to broadly ovate or orbicular, 4-16 × 3.5-9.5 cm, papery, both surfaces glabrous except vein axils abaxially barbate, midvein and lateral veins conspicuous abaxially, sulcate adaxially, lateral veins 6 or 7 pairs, reticulate veinlets conspicuous with subconspicuous parallel cross-bars, base rounded to truncate or cordatulate, oblique or not, margin shallowly mucronate-serrate, teeth produced by tips of veinlets, reddish, glandular, apex obtuse to mucronate or long acuminate. Inflorescences cymose, axillary, brownish velutinous. Male inflorescences many flowered. Female inflorescences few flowered. Flowers white. Sepals 5, ovate, ca. 5 mm, both surfaces brownish velutinous, apex acute. Petals obovate, ca. 1 cm. Ovary globose, ca. 6 mm, densely brownish tomentose. Fruit oblong to ovoid, 1.5-2.5 cm, glabrous, lenticels obscure. Fl. and fr. unknown.
Actinidia rufa var. parvifolia Dunn (J. Linn. Soc., Bot. 39: 403. 1911), described from Hubei, could not be treated here because no material was seen by the authors.
Mountain forests; 1000-2000 m. Taiwan [Japan, Korea].