Psychotria triphylla (DC.) M.-Arg., Mart. FI. Bras. 6(5): 233. 1881.
Psychotria ternata Urb., Symb. Ant. 7: 547. 1913.
This taxon was described from fruiting material from “Guiana Gallica” from material collected by Patris, but the label on the type photo from Delessert Herbarium at G reads “Cayenne.” Variation is found in the glabrity of the lower surface of the leaf blades, from glabrous to pubescent, and in the number of lateral nerves, most of the material from the Guianas, Venezuela, and northern Brazil having 13-14 nerves on each side 6-9 mm apart, but in some of the Brazilian specimens the lateral nerves are 17-22 on each side. In some of the Brazilian material (Holt & Blake 621, Tate 85, Black 48-2909) the peduncle and inflorescence branches are more pubescent than usual. An extreme in the amount of puberulous hairs on the hypanthium and calyx, as well as on the corolla is attained in Holt & Blake 621. The calyx varies from glabrate to densely pubescent. Specimens from Bolivia and from some parts of the Amazonian Brazil area (Weiss & Schmidt, Holt & Blake 621) have more abbreviated and more congested inflorescences often only 4.5-5.5 cm long.
The Trinidad material, referred by Urban to P. ternata, is typical P. triphylla, possessing inflorescences 9-13 cm long, 3-4 cm broad at base, peduncles 6-11 cm long, and lobes of the stipules 10-12 mm long. Palicourea macrobotrys has sometimes been misidentified with P. triphylla. Steyermark 57873 from the base of Duida was originally identified by Standley as P. macrobotrys (Fieldiana Bot. 28: 1105. 1957). Palicourea triphylla is easily distinguished from P. macrobotrys by the ternate instead of opposite leaves, longer lobes of the stipules, and shorter petioles. It is more often confused with P. calophylla DC., from which it may be differentiated by the usually longer lobes of the stipules, more conspicuously acute to acuminate calyx lobes with more spreading pilosulous hairs, the usually soft pilosulous lower leaf surface, midrib, and lateral nerves, longer and more conspicuous, subulate inflorescence bracts, 6 instead of 4 lobes of the stipules, smaller and shorter fruits with the smaller ribs closer together, and lack of calycine glands on the interior of the calyx tube.