Cremocarpon as circumscribed by Bremekamp had its center of diversity in Madagascar, but was also found in the Comores (1 species) and New Caledonia (1 species). Cremocarpon was unusual morphologically and often overlooked, in particular it has been often confused with Psychotria. The species included in Cremocarpon are similar to Psychotria, with raphides in its tissues; a shrub habit; deciduous to persistent stipules that are interpetiolar or fused around the stem and triangular to rounded or bilobed on each interpetiolar side of the stem; terminal, cymose, pedunculate inflorescences with reduced bracts; 4- or 5-merous distylous flowers; salverform white corollas with valvate lobes; and bilocular ovaries with a single basal ovule in each locule. However the species included in Cremocarpon differed from Psychotria in their unusual schizocarpous fruits, vs. generally subglobose fruits that are fleshy and red to black at maturity with the pyrenes immersed in the flesh and the entire fruit dispersing as a single unit in Psychotria. The fruits of the species included in Cremocarpon are ultimately (apparently) dry and ellipsoid to oblong-ellipsoid, and at maturity the fruits split along the septum into two mericarps, each with one seed and corresponding to the pyrene of Psychotria. See Bremekamp (1958: p. 148) for an analytic illustration. These mericarps are supported by a simple to branched carpophore, generally in the shape of a horse shoe with the pedicel connected at the rounded basal portion. The species included in Cremocarpon can often be recognized in young fruit, before the formation of the mericarps is evident, by the disks that become enlarged. In some species these disks become widened and smooth and are not very different from those of Psychotria, but in several species the disk and calyx limb both enlarge as the fruit develops, with the disk equal to or a little longer than the persistent calyx limb.
Cremocarpon was separated by Bremekamp based on the unusual fruits, dry and schizocarpous. However Razafimandimbison et al. (2014) found in their molecular analyses found that dry schizocarpous fruits have arisen several times independently within Psychotria, and they synonymized the two genera with these fruits, Cremocarpon and Pyragra, with Psychotria.
In general aspect the species of Cremocarpon are similar to most species of Psychotria (apart from the fruit morphology), except in most species of Psychotria the stipules are deciduous exposing a line of persistent trichomes along the stipule scar, while the stipules of the species included in Cremocarpon are generally persistent or when they do fall, the adaxial stipule trichomes also fall off. Also the disk in most species of Psychotria shrinks as the fruits mature, and is not well developed on the mature fruits. Species included in Cremocarpon are in particular similar to and apparently closely related to the species previously included in Pyragra, walso found in Madagascar and also with schizocarpous fruits. However the fruits of the species that were included in Pyragra are ovate and strongly laterally flattened, and have the inflorescences displaced to pseudoaxillary soon after flowering.
Several of the species from Madagascar that were included in Cremocarpon are similar in their thin-textured, often small leaves that are frequently borne on shortened lateral stems and well developed, slender peduncles and pedicels. Several other species are quite different from these, and share well developed, thick-textured leaves and sessile or very shortly pedicellate flowers. Psychotria trichantha is not similar to any of the other species that were included in Cremocarpon, with densely hirtellous pubescence, sessile to subsessile flowers in close groups, obovate leaves with well developed venation (the leaves in fact are quite similar to those of Psychotria macrochlamys), and seeds with ruminate endosperm; it is not clear that Bremekamp saw mature, schizocarpous fruits for this species, or perhaps only saw immature fruits with well developed fibers that resembled developing carpophores. Such fibers are found in the young fruits of several fleshy-fruited species of Psychotria and Palicourea.