Lettsomia Roxburgh; Moorcroftia Choisy.

Shrubs, scandent or lianas. Stems woody. Leaves petiolate, entire, sometimes silvery sericeous abaxially. Inflorescences axillary, rarely terminal, in cymes, or loose or compact capitula, few to many flowered; bracts persistent or early deciduous, small or large. Sepals persistent, herbaceous or ± leathery, pubescent abaxially, glabrous and often red adaxially, ± enlarged and reflexed in fruit. Corolla purple, red, pink, or white, campanulate, funnelform, or tubular; limb subentire to deeply 5-lobed, with 5 distinct, mostly pubescent midpetaline bands. Stamens inserted near base of corolla, included or exserted; filaments filiform, base dilated, often pubescent or glandular; pollen globular, pantoporate, finely spiny. Disc ringlike or cupular, margin entire or shallowly 5-lobed. Ovary 2- or 4-loculed, 4-ovuled, pubescent or glabrous. Style 1, filiform, included or exserted; stigma capitate, 2-lobed or 2-globular. Berry red, purplish, orange, or yellowish, globose or ellipsoid, fleshy, mealy, or leathery. Seeds 4 or fewer, rarely pilose at hilum.

About 90 species: mainly tropical Asia, with one species in Australia (Queensland); 22 species in China.

No monograph of Argyreia exists, and the mainland Asian species have not been studied for a contemporary flora or regional revision. A comparison of the Chinese material with those from regions to the south reveals that a profusion of names has developed for what appears to be a significantly smaller number of taxa. It was not possible to sort out the nomenclature for the species involved due to the lack of access to type material and the exceedingly complex literature dealing with Argyreia. Therefore, a conservative approach is taken, and nearly all of the taxa described from China are maintained, and possible conspecific taxa are pointed out. The flowers of Argyreia marlipoensis are unknown. It has not been possible to place the species in a key that relies heavily on floral characters. One cultivated species, A. nervosa, is included in the key but not treated further.