Monographs Details: Psychotria erecta f. fluctuans (Standl.) Steyerm.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.

Psychotria fluctuans Standl., Field Mus. Publ. Bot. 7: 446. 1931.

Ronabea latifolia var hispidula Brem., Rec. Trav. Bot. Neerl. 31: 291. 1934.

Coffea subsessilis Benth. in Hook., Jour. Bot. 3: 232. 1841, not Psychotria subsessilis Benth. 1882.

Mapouria subsessilis (Benth.) M.-Arg. var genuina M.-Arg., Mart. FI. Bras. 6(5): 411. 1881.

Mapouria subsessilis (Benth.) M.-Arg., Flora 59: 460. 1876.

Mapouria subsessilis M.-Arg. a latifolia M.-Arg., Mart. FI. Bras. 6(5): 410. 1881.

Psychotria fluctuans var latifolia (M.-Arg.) Standi., Field Mus. Publ. Bot. 7: 448. 1931.

The leaves of the Lehmann 9020 and Haught 1355 collections attain 9-9.5 cm in width. The habit of Psychotria erecta simulates that of P. emetica L.f. The entire, strigillose, long acuminate stipules of P. erecta much resemble those of Bertiera, and the entire or subentire, subtruncate, cylindric calyx and hypanthium with closely flowered axillary inflorescences much resembles the genus Morinda (Appunia), but the ovary and fruit are those of Psychotria. The 3-7 flowers are in small axillary heads surrounded by a lobed densely strigillose involucre. The commissural face of the pyrene is flat and without any furrow.

An examination of the isotype of Coffea subsessilis Benth. at US (Schomburgk 994) shows a lower midrib with sparsely substrigose buff pubescence and to a lesser extent also along the lower lateral nerves, while the lower surface of the leaf is glabrous. This pubescent-leaved taxon was placed by Müller-Argoviensis under Mapouria subsessilis var genuina, the Schomburgk 994 being the basionym of both Coffea subsessilis and Mapouria subsessilis var genuina. Standley created a new name, Psychotria fluctuans, for Coffea subsessilis Benth., not Psychotria subsessilis Benth.