Key to Psychotria cardiomorpha and Similar Species

1. Plants densely hirtellous; leaves bullulate; stipule lobes 5-12 mm long.....Palicourea huberi Steyerm.

1'. Plants glabrous; leaves plane; stipule lobes 0.5-3.5 mm long.

    2. Inflorescences subcapitate to shortly branched to 1--2 orders, with bracts subtending the flowers or groups of flowers 4--12 mm long and elliptic, ovate, or pandurate....Psychotria arirambana Standl.

    2'. Inflorescences cymose or paniculiform, branched to 2--5 orders, with bracts subtending the flowers or flower groups 0.5--2.5 mm long and narrowly triangular.

        3. Leaves 10-16 x 5.5-12 cm, with 12-13 pairs of secondary veins; stipules with broadly triangular lobes; inflorescences with branched portion 9--12 x 5--7 cm.....Psychotria sipapoensis Steyerm.

        3'. Leaves 2.5-10.5 x 1.2-7 cm, with 6-12 pairs of secondary veins; stipules with narrowly triangular lobes; inflorescences with branched portion 1-8 x 1-5 cm.

            4. Calyx limb with tubular portion 0.3-0.5 mm long and denticulate or with lobes to 0.3 mm long and shorter than the tube; corolla white, with tube 2-3 mm long.....Psychotria cardiomorpha C.M. Taylor & A. Pool

            4'. Calyx limb 1-1.5 mm long and lobed for two thirds or more of its length; corolla yellow, red, or pink, with tube 6-6.5 mm long.

                5. Leaves erect to ascending,2.5-7 cm wide, at apex acute to acuminate, with 8-12 pairs of secondary veins and margins generally flat.....Palicourea foldatsii Steyerm.

                5'. Leaves deflexed, 1.2-3.5 cm wide, with 5-9 pairs of secondary veins and margins usually thinly revolute.....Palicourea lancigera (Standl.) Steyerm.