Monographs Details: Mitracarpus frigidus var. fruticosus Steyerm.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
Family:Rubiaceae
Discussion:

Mitracarpus fruticosus Standl., Lloydia 2: 215. 1939.

This taxon cannot be sharply separated from M. frigidus as a species, since M. frigidus likewise has a suffruticose habit. In general, the leaves of var fruticosus are relatively broader in proportion to the length than those of var frigidus, the shorter pair of calyx lobes are shorter than those of var frigidus, and the corollas are slightly shorter (4.5-5 mm), but in other details the characters of the two varieties merge with one another.