3. Coffea congensis Froehner, Notizbl. Königl. Bot. Gart. Berlin. 1: 235. 1897.
刚果咖啡 gang guo ka fei
Shrubs, 2-6 m tall; branches flattened, glabrous. Petiole 5-10 mm, glabrous; leaf blade drying thinly leathery, elliptic-oblong to ovate or lanceolate-elliptic, 8-15 × 3-7 cm, glabrous on both surfaces, base cuneate or obtuse to rounded, apex acute to shortly acuminate with tip 5-10 mm; lateral veins 6-9 pairs, usually with pilosulous domatia; stipules triangular to broadly triangular, 2-5 mm, obtuse to acute but not aristate. Inflorescences with cymes 1-4 in each axil, each cyme subcapitate to fasciculate, 2-4-flowered, sessile to pedunculate with peduncles to 4 mm; bracts cupuliform, 1-3 mm; pedicels to 3 mm. Calyx glabrous; ovary portion cylindrical-ellipsoid, 1-1.5 mm; limb reduced or undulate, 0.1-0.5 mm. Corolla white, funnelform, outside glabrous; tube 7-10 mm; lobes 5 or 6, spatulate to narrowly elliptic, 7-10 mm, obtuse to rounded. Drupe red, ellipsoid to ovoid-oblong, 10-12 × 8-10 mm, smooth when dry, glabrous. Fr. Dec.
Cultivated in moist forest regions. Hainan [native to Africa (Congo River basin: Democratic Republic of Congo, Republic of Congo), growing as rheophyte; widely planted in tropical regions, though perhaps not so often in recent decades].
This species is presumably diploid and has been occasionally hybridized with other species to produce commercial coffee (Purseglove, Trop. Crops: Dicot. 458. 1968; Bridson, Fl. Trop. E. Africa, Rub. (Pt. 2), 703. 1988).