Monographs Details: Psychotria lupulina subsp. rhodoleuca (Müll.Arg.) Steyerm.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
Family:Rubiaceae
Discussion:

Psychotria rhodoleuca M.-Arg., Flora 59: 541, 545. 1876; Mart. Fl. Bras. 6(5): 314. pl. 49, figl. 1881.

Psychotria persimilis M.-Arg., Flora 59: 541, 545, 1876; Mart. Fl. Bras. 6(5): 315. 1881.

Psychotria flavovirens Suessenguth, Rev. Sudam. Bot. 7(6): 168. 1943.

Psychotria langsdorffiana M.-Arg., Flora Ratisb. 59: 541, 545. 1876; Mart. Fl. Bras. 6(5): 316. 1881.

The collection of Maguire & Politi 27379 is a mixture of the narrow-bracted subsp rhodoleuca and broader-bracted subsp lupulina, and shows introgression in the colony from which the material was obtained. A collection from Estado Goias, Brazil (Irwin, Maxwell & Wasshausen 19385 from Planalto do Brasil: Serra dos Pirineus, Pico dos Pirineus, ca 20 km NW of Corumba de Goias near road to Niquelandia, alt 1400 m, 28 Jan 1968) is likewise intermediate between subsp lupulina and subsp rhodoleuca. I have not been able to maintain Psychotria langsdorffiana M.-Arg. separate from subsp rhodoleuca. The glabrous hypanthium is found in both P. rhodoleuca and P. persimilis. The relative length of the lobes of the corolla as compared with the length of the tube (lobes five times shorter than the tube stated for P. langsdorffiana) has not been found to be a character of reliability. Likewise, Psychotria flavovirens Suesseng. matches in all respects both P. rhodoleuca and P. persimilis. Although Suessenguth described the involucral bracts as glabrous, they are found to be minutely ciliolate, as in the other specimens assigned to subsp rhodoleuca.

The general arrangement of bracts and flowers is that of an ultimate group of 5 flowers subtended by 5 bracts, an outermost larger one subtending the base of a solitary central flower and 2 bracts each subtending a pair of flowers (four bracts for two pairs of flowers).