Cephaelis hirta Miq., Linnaea 17: 71. 1843; Linnaea 18: 297. 1844, not Psychotria hirta H. & B. ex R. & S., 1819, nor P. hirta H.B.K., 1819.
Petagomoa hirta (Miq.) Brem., Rec. Trav. Bot. Neerl. 31: 295. 1934.
Uragoga hirta (Miq.) Pulle, Enum. Pl. Sur. 446. 1906.
This taxon differs from other similarly pubescent-stemmed species in the narrowly and cuneately based leaf-blades. Neither the type specimen of Focke 382, upon which Miquel based his Cephaelis hirta, nor the collection of Hulk 264 referred to by Bremekamp in his treatment of Petagomoa hirta, bear flowers. Nevertheless, Bremekamp placed this species in Petagomoa, which, according to his generic key under “47a.” (Ribiaceae in Pulle, Fl. Surin. 4(1): 123. 1934), should have “the individual flowers with their own bracts and bracteoles.” However, examination of flowering heads of several specimens of this taxon (J. & P. A. Florschutz 701 and Silva 1538) shows that most of the flowers of a head are, indeed, without bracts or bracteoles, and, therefore, could not fall into Petagomoa, but would have to key out in that part of Bremekamp’s generic key reserved for Psychotria. The possession of a longitudinal ventral fissure of the pyrene, characteristic also of Petagomoa, is present in this taxon, but the character of the individual flowers having their own bracts and bracteoles is lacking. As has been mentioned elsewhere, such non-correlation of characters within segregates of Psychotria and Cephaelis concepts minimizes the prospects of retaining such segregates in the generic category. Actually, in P. bremekampiana, only the outermost row of flowers is subtended on their outer side by the involucral bracts, whereas the rest of the flowers lack bracts or bracteoles. All the bracts of the inflorescence are free to their bases.