Paullinia cupana Kunth

Shrub or liana to 5 m long. Stems obtusely pentagonal, sulcate, puberulent; cross section with a single vascular cylinder. Stipules minute, deltoid, 2-3 mm long, tomentulose, persistent. Leaves pinnately 5-foliolate; petiole and rachis unwinged, puberulent or glabrous; petioles 11-20 cm long; rachis 7-12.5 cm long; petiolules puberulent, 5-15 mm long; leaflets chartaceous, adaxial surface glabrous, abaxial surface sparsely, minutely pubescent, with microscopic scurfy-like papillae, oblong-elliptic or elliptic, 11-30 × 7-11 cm, the base acute, obtuse to subrounded on lateral leaflets, attenuate or cuneate on distal leaflets, the apex narrowing into an acute broad apiculum with rounded tip, the margins grossly crenate or sinuate dentate with glandular tooth; tertiary veins slightly prominent, sub-clathrate. Thyrses axillary, racemiform, solitary, puberulent; bracts and bracteoles deltate, minute, tomentulose; cincinni sessile, 5-8-flowered. Calyx green, tomentulose, with 5 sepals, the margins with minute glandular hairs, outer sepals 2.5-3.2 mm long, inner sepals ca. 4 mm long; petals white, oblong, 4-5.5 mm long; disc tomentulose, with 4 ovate, glabrous lobes, ca. 1 mm long; gynoecium glabrous. Capsule ellipsoid to subglobose, 6-ridged, unwinged, maturing red, glabrous, 1-2-seeded, long-stipitate; endocarp tomentose. Seeds ovoid, dark brown, with a white, fleshy sarcotesta on lower ½ to ⅓

A tropical plant. It grows in the Amazon rainforest. It is along the Madeira and Tapajos rivers. It grows in regions with a rainfall of 2,200-2,500 m altitude. The temperatures average 28°-29°C. It must have a temperature above 12°C. It suits hardiness zones 11-12.

The seeds are extracted and roasted and used as a stimulant. It contains caffeine. The seeds are roasted for several hours then beaten into a paste and smoked for about 2 months before being ground in a powder. It is used as a stimulant in water and used to flavour drinks. They are used as the base for a drink called guarana.

Plants are grown from seed. Seed need to be sown very fresh. Seeds can become non viable after 72 hours in storage. Seeds may take 100 days to germinate. Plants are fertilized by bees. It grows on poor acid soils. The soil pH is 3.5-4.5. It cn grow in soils with high concentration of aluminium. A spacing of 4-5 m part is used. Cuttings and grafts can be used with misting chambers.