Monographs Details: Palicourea longiflora (Aubl.) Rich.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
Family:Rubiaceae
Discussion:

Nonatelia longiflora Aubl., Pl. Guian. 1: 185. pl. 71. 1775.

Psychotria longiflora Willd., Sp. Pl. 1: 971. 1797, not Poir. 704. 1804.

Psychotria diversicolor M.-Arg., Mart. Fl. Bras. 6(5): 252. 1881.

Bremekamp (Rec. Trav. Bot. Néerl. 31: 300. 1934) adopted the name Palicourea longiflora (Aubl.) Rich. as the proper epithet for this taxon, following Richard’s transference of Nonatelia longiflora Aubl. to Palicourea, although it was believed that Aublet’s type specimen had been lost. Later, in 1940 Lanjouw & Uittien (Rec. Trav. Bot. Neerl. 37: 133-170) were able to show that the type specimen was not lost, but appeared in the Rousseau herbarium in the possession of M. Henri Denaiffe, and assignment of the generic status of the plant to Palicourea confirmed.

I am tentatively following the above interpretation, as there are some doubts as to whether the name Nonatelia longiflora has been applied to the proper species of Palicourea. I refer here to the matter of the interpretation of the corolla color in Aublet’s description as “purpurascens” (Hist. Pl. Guian. 1: 185. 1775). The corolla color, along with various other details of the description, such as “folia . . . glabra” and the elongated corolla shown on plate 71 of Nonatelia longiflora, might be construed to apply to an entirely different taxon known from a region bordering French Guiana in Territorio Amapa, Brazil, in which the corollas are completely purple with an elongated tube and glabrous leaves, which I have called Palicourea amapaënsis.

In analyzing the similarities and differences between these two taxa, the following situation presents itself: (1) color notes made by collectors of the plants currently assigned to Palicourea longiflora indicate that the corollas are orange-yellow or yellow in the lower portion but the lobes are purple, violet, or blue with an occasional label indicating the corollas as yellow only; (2) Aublet describes the leaves as glabrous, but the plants passing currently as P. longiflora have the petiole abundantly puberulous and the leaf blades more often minutely and moderately puberulent above and abundantly puberulous below on the surface, midrib, and lateral nerves, although nearly glabrous leaf blades on both sides are also evident. On the other hand, the taxon described below as Palicourea amapaënsis from Amapa, Brazil and French Guiana shows more elongated and completely purple, purplish, or violet corollas, according to the collectors’ notes, and have completely glabrous leaves. The word “purpurascens” in Aublet’s description might apply, therefore, either to the corollas as a whole, as in the case of the plants of Amapa and French Guiana, or only to the upper portion or lobes of the corolla, as in the case of the current interpretation by Bremekamp for P. longiflora.

Aublet described the petioles of Nonatelia longiflora as “court.” This applies better to the relatively short petioles, varying from usually 3-8 (-15) mm long, of P. longiflora, as currently interpreted, rather than to the more elongated ones of 10-20 mm in length of Palicourea amapaënsis. Moreover, the plants presently passing as Palicourea longiflora are widespread in their distribution, and have been commonly collected in French Guiana, where Nonatelia longiflora was originally found in the Oyac region, whereas the taxon, P. amapaënsis appears to be of local occurrence with only three specimens known from French Guiana in the extensive collections I have examined from the Paris herbarium.