Psychotria hoffmannseggiana (Willd. ex, R. & S.) M.-Arg., Mart. Fl. Bras. 6(5): 336. 1881.
The name Cephaelis hoffmannseggiana was used by Roemer & Schultes instead of the manuscript name of Cephaelis dichotoma Willd. The latter, if published, would have duplicated the already published Cephaelis dichotoma Rudge (Pl. Guian. 20. pl. 44. 1805), an entirely different species.
Bremekamp confused P. hoffmannseggiana with P. officinalis and P. barbiflora in his Rubiaceae of Suriname (in Pulle, Fl. Sur. 4(1): 263-265. 1934). From P. barbiflora, the earliest name for the species mistaken by most authors for P. involucrata, P. hoffmannseggiana is distinguished by the proportionately narrower and longer bracts subtending the head (usually 3-10 times longer than broad) which are longer than or as long as the diameter of the head, the generally smaller heads, and generally smaller, fewer nerved leaves of different texture. Hostmann 952, from Suriname, cited by Bremekamp under P. barbiflora, cannot be distinguished from the type of Cephaelis microcephala Miq. (basionym of Psychotria microcephala (Miq.) Miq. collected by Kappler from Suriname. The heads in P. hoffmannseggiana [and P. microcephala (Miq.) Miq.] vary during anthesis from those appearing capitate and monocephalous to ones more loosely branched with fascicles of flowers at the ends of 3-4 subumbellately branched short rays, as in the type collection of Cephaelis microcephala Miq. (Kappler 1562).
The hypanthium and calyx of Psychotria hoffmannseggiana vary from completely glabrous, as in the type collection of Cephaelis microcephala Miq. and Psychotria barbiflora var amazonica M.-Arg. to densely pubescent. Likewise, the calyx lobes are depressed-suborbicular and rounded in Kappler 1562 (type of Cephaelis microcephala Miq.), or depressed-triangular and subacute in Hostmann 952 to irregularly triangular and acute to acuminate in J. & P. A. Florschutz 1446 from Suriname.
Müller-Argoviensis attempted to keep Psychotria hoffmanseggiana and P. rubra separated by such key characters as “baccae non costate, pedunculus erectus” for P. hoffmannseggiana and “baccae costatae, pedunculus nutans” for P. rubra (Mart. Fl. Bras. 6(5): 321. 1881). A study of all the material available shows that these differences do not hold, since nodding peduncles are found throughout collections of P. hoffmannseggiana, and differences of fruits are not discernible.
In some of the Suriname specimens (Kramer & Hekking 2922 and J. & P. A. Florschutz 1446) the bracts subtending the heads in anthesis are described as “white with green tip” or “white, inside often green, the outer ones red at the apex,” but also are described as “green, pinkish-red at fruiting time” (J. & P. A. Florschutz 1292), or “reddish” (J. & P. A. Florschutz 1457). Also, an occasional specimen from British Guiana (Forest Dept. Field no. 385) is recorded as having white bracts, but in the majority of the specimens examined from Venezuela and other areas, the bracts at anthesis are recorded as often “deep purple,” “dull purple,” “green turning red,” “purplish at base, greenish above,” or “green” or “pale green” or in fruit “wine purple” or “purple with green tips.” It is interesting to note here that, although the labels of the Venezuelan plants often record the flowers as white or whitish, no mention is made of the color of the bracts as “white with green” or “white,” as on some of the specimens noted from Suriname.
In most instances, the exterior of the corolla is more or less pilosulous or hirtellous, but in J. & P. A. Florschutz 1446 the exterior is glabrous and the calyx lobes are more irregularly triangular with a more prolonged acute to acuminate apex.