Description from Flora of China
Deciduous or evergreen, often thorny trees, shrubs, woody climbers, or lianas, rarely herbs. Leaves simple, petiolate, alternate or opposite, pinnately veined or 3-5-veined, entire to serrate, sometimes much reduced; stipules small, caducous or persistent, sometimes transformed into spines. Flowers yellowish to greenish, rarely brightly colored, small, bisexual or unisexual, rarely polygamous, (4 or)5-merous, hypogynous to epigynous, in mostly axillary, sessile or pedunculate cymes, or reduced to few in fascicles. Calyx tube patelliform or hemispherical to tubular, sometimes absent, at rim with calyx, corolla, and stamens; sepals 4 or 5, valvate in bud, triangular, erect or ± recurved during anthesis, adaxially often distinctly keeled, alternate with petals. Petals 4 or 5, rarely absent, usually smaller than sepals, concave or hooded, rarely nearly flat, often shortly clawed. Stamens 4 or 5, antepetalous and often ± enclosed by petals; filaments thin, adnate to bases of petals; anthers minute, versatile or not, 2(or 4)-celled, dehiscing by longitudinal slits, usually introrse. Disk intrastaminal, nectariferous, thin to ± fleshy, entire or lobed, glabrous or rarely pubescent, free from ovary or tightly surrounding it, or adnate to calyx tube. Ovary superior to inferior, (1 or)2-4-loculed, with 1(or 2) ovules per locule; ovules anatropous, basal and erect; styles simple or ± deeply 3-lobed or 3-cleft. Fruit either an indehiscent, rarely explosively dehiscent, sometimes winged, schizocarpic capsule, or a ± fleshy drupe with 1-4 indehiscent, rarely dehiscent, pyrenes (stones). Seeds with thin, oily albumen, sometimes exalbuminous; embryo large, oily, straight or rarely bent.
Former classifications usually placed Rhamnaceae in the Rhamnales, together with Vitaceae and Leeaceae (Suessenguth in Engler & Prantl, Nat. Pflanzenfam., ed. 2, 20d. 1953), or together with Elaeagnaceae (Thorne, Bot. Rev. 58: 225-348. 1992). Orders such as Celastrales, Urticales, and Euphorbiales have often been considered as closely related groups. Recent analyses of DNA sequences strongly supported including the family in the Rosales, beside the closest relatives Barbeyaceae and Dirachmaceae (see Angiosperm Phylogeny Group II, Bot. J. Linn. Soc. 141: 399-436. 2003). Suessenguth (loc. cit.) grouped the family into five tribes, mainly characterized by fruit characters. Richardson et al. (Kew Bull. 55: 311-340. 2000; Amer. J. Bot. 87: 1309-1324. 2000) revised this tribal classification on the basis of a phylogenetic analysis using rbcL and trnL-F sequences of the plastid genome. Now 11 tribes are recognized, of which four are represented in the Flora area.
Microrhamnus bodinieri H. Léveillé (Fl. Kouy-Tchéou, 341. 1914-1915) is a synonym of Nyssa sinensis Oliver in the Nyssaceae (see Fl. China 13: 302. 2007).
The bark, leaves, and fruit of several species of Rhamnus have been used as laxatives, notably R. cathartica and R. frangula. Diverse Old World species of Rhamnus provide yellow and green dyes as well as drugs. Timber of Alphitonia, Colubrina, Hovenia, and Ziziphus species is used for construction, fine furniture, carving, lathework, and musical instruments. Many Ziziphus species yield edible fruit; among them, Z. jujuba (Chinese jujube) and Z. mauritiana (Indian jujube) are cultivated on a commercial scale. Hovenia dulcis is also grown for its edible, fleshy inflorescence stalks. Species of Hovenia, Paliurus, and Rhamnus are cultivated as ornamentals.
Chen Yi-ling & Chou Pan-kai. 1982. Rhamnaceae. In: Chen Yi-ling, ed., Fl. Reipubl. Popularis Sin. 48(1): i-vi, 1-169.
About 50 genera and more than 900 species: almost cosmopolitan, mainly in subtropical to tropical areas; 13 genera and 137 species (82 endemic, one introduced) in China.
(Authors: Chen Yilin (陈艺林 Chen Yi-ling); Carsten Schirarend)