Psychotria rigida Bredem. ex R. & S., Syst. Veg. 5: 192. 1819.
A number of varieties and forms have been described under P. rigida, some of which, as treated by Müller-Argoviensis in Martius’s Flora Brasiliensis (6(5): 230-231. 1881), appear distinctive and confined to portions of the Brazilian Planalto. Venezuelan material of typical Palicourea rigida varies from the lower leaf surface normally glabrous to minutely and sparsely puberulent to densely puberulent on surface, midrib, and lateral nerves, from rounded and shallow calyx lobes to broadly triangular and acute to acuminate lobes, from minutely and densely puberulent to glabrate or subglabrous inflorescence branches, from glabrous to minutely puberulent rachis, from glabrous to densely puberulent pedicels, from lanceolate to ovate bracts of the inflorescence 1-2 mm long, from subobtuse to acute corolla lobes, and from normally glabrous to rarely densely pubescent fruits.
The Venezuelan variation with fruits densely pubescent and densely pubescent lower surface, midrib, and lateral nerves of leaf blades merits recognition as follows: