1. Anacardium occidentale Linnaeus, Sp. Pl. 1: 383. 1753.
腰果 yao guo
Trees or shrubs, 4-10 m tall; branchlets glabrous to subglabrous. Petiole 1-1.5 cm; leaf blade obovate, 8-11 × 6-8.5 cm, leathery, glabrous on both sides, base broadly cuneate, margin entire, apex rounded, truncate to retuse, lateral veins ca. 12 pairs, reticulate venation pattern prominent on both sides. Inflorescence paniculate, 10-20 cm, glabrous to densely grayish sericeous; floral subtending bracts ovate-lanceolate, 5-10 mm, keeled, grayish sericeous abaxially, glabrous adaxially. Flower sessile to shortly pedicellate. Calyx grayish sericeous abaxially, ca. 4 × 1.5 mm. Petals 5, greenish yellow to red, linear-lanceolate, 7-9 × ca. 1.2 mm, grayish sericeous abaxially, minutely pubescent to subglabrous adaxially. Stamens 7-10, larger one 8-9 mm in male flowers, 5-6 mm in bisexual flowers, sterile stamens 3-4 mm. Ovary ca. 2 mm, glabrous; style 4-5 mm. Fleshy hypocarp 3-7 × 4-5 cm, purplish red at maturity; drupe reniform, 2-2.5 × ca. 1.5 cm. Fl. Mar-Apr, fr. Jul-Aug.
Cultivated. Fujian, Guangdong, Guangxi, Taiwan, Yunnan [native to tropical America].
The edible seeds are referred to as cashew nuts. They are surrounded by a leathery shell (mesocarp), which is rich in liquid. This substance is an important raw material for resin. The liquid contains skin-irritant toxic compounds, which are removed by heating. The fleshy hypocarp, or cashew apple, is processed into jam and dried fruit.