This species is characterized by its slender, generally glabrescent to puberulous habit; its rather small, elliptic to lanceolate, quite thin-textured leaves with the venation closely reticulated and visible on the lower surface and without any domatia; its small bilobed stipules; its several-flowered, pedunculate, cymose inflorescences; its subsessile to pedicellate, variously 4-merous and 5-merous flowers with a short calyx and short yellow corolla; and its rather small red fruits. The name Psychotria ambongensis is here used for a species that has been commomnly collected in Montagne d'Ambre; these appear from web images to be conspecific but this needs re-evaluation when original material of this species can be studied. The plants from Montagne d'Ambre frequently appear to have at least some stipules that are entire and acuminate, but these are difficult to separate from stipules with two lobes that rae closely set and also this form appears to vary among the plants. These plants appear to be decidous, with the inflorescences produced with the new leaves (e.g., McPherson 14506.

This species was described by Bremekamp in Mapouria where he considered it related to Psychotria ankafinensis and Psychotria baronii; those species both have rather stiff-textured leaves with the venation mostly not evident. In general aspect and in particular the well marked and closely reticulated leaf venation Psychotria ambongensis is similar to sevral species that Bremekamp described in Apomuria, but those differ in their seeds with a T-shaped adaxial furrow.