This species is characterized by its quite resinous stems and inflorescences, rather robust leaves, narrowly racemiform inflorecences with the primary axis ridged and a dozen or more flowers, a truncate involucel, stout pedicels 1-4 mm long, white to pink corollas with tubes 10-24 mm long and markedly reflexed lobes, and unwinged pyrenes. The leaves are various elliptic, elliptic-oblong, or in most cases obovate. The corollas are zygomorphic due to the asymmetric arrangement of the lobes and the bent style, and have lines that appear to be pollination guides. These corollas have lobes about half as long as the slender tubes. The dried fruits have a 5-ribbed appearance, with one ridge for each pyrene.

Retiniphyllum chloranthum is similar to Retiniphyllum concolor, which has entire involucels, unwinged pyrenes, 5-ribbed dry fruits, and leaves that are often oblanceolate or obovate. These two species grow together in much of their ranges and are often confused.

Retiniphyllum concolor and Retiniphyllum chloranthum were confused in particular by Mueller (1881), who was followed by many later authors. Cortés-Ballén (2003, and in Taylor et al. 2004) traced that confusion to Mueller's use of a mixed set of specimens to characterize Retiniphyllum concolor, Spruce 2028, the type collection studied by Bentham, and Spruce 3535, which is a mixed collection including both of these species. As a result, he characterized this species by contradictory characters. His application in practice of the name Retiniphyllum concolor was to the plants with lobed involucels that are here called Retiniphyllum chloranthum. This resulted in his describing a new species, Retiniphyllum martianum, for the plants with truncate involucels even though those plants matched the type of Retiniphyllum concolor. Later this confusion over the characters of Retiniphyllum concolor resulted in another confusion, Ducke's describing the new species Retiniphyllum chloranthum for plants that Mueller included in Retiniphyllum concolor. The corrected application by Cortés-Ballén of the name Retiniphyllum concolor results now in two name changes: the name Retiniphyllum chloranthum applies to the plants tresated by Mueller and Steyermark (1965) as Retiniphyllum concolor, and the name Retiniphyllum concolor applies to the plants previously treated as Retiniphyllum martianum. Cortés-Ballén also has clarified the characters of Retiniphyllum concolor.