Compilation
Psychotria robynsiana

I am unable to accept this as a separate species. Petit himself mentions that it was very difficult to obtain a satisfying arrangement for P. megistosticta and its allies, but his division into quite a number of species is not in accordance with the facts. The amount of indumentum varies greatly in one place, e.g. Sese Is. In the text P. robynsiana is separated from P. megistosticta by having larger leaf-blades with more lateral nerves and larger inflorescences, but he describes two varieties glabra and pauciorinervata which totally blur this distinction. In the main key the two are separated on the presence or absence of distinct domatia but two of his varieties of P. megistosticta, puberula and punicea, usually also lack them. P. mushiticola Petit (Type: Zaire, Parc National de l’Upemba, R. Kamitano, near Lusinga, Van Meel in de Witte 5122), separated from P. robynsiana by having fewer lateral nerves and corolla puberulous outside, clearly is not distinct but may perhaps be considered another minor variant; much of the cited material of P. robynsiana has quite distinctly tomentose flowers. If it is not separated, Zambia must be added to the distribution. P. mahonii he dismissed as a dubious species, but the material is quite adequate so it must be accepted as the earliest name for this taxon as a whole; typical var. mahonii, from Malawi, has dense ferruginous hairs on the inflorescence branches.