Monographs Details: Diodia hyssopifolia var. articulata (Pohl ex DC.) Steyerm.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
Family:Rubiaceae
Discussion:

Diodia articulata Pohl ex DC., Prodr. 4: 564. 1830.

Diodia surinamensis Miq., Stirp. Sur. 180. 1850.

This taxon appears to represent an intermediate type of variation, with elongate calyx lobes characteristic of var linearis, but with the narrower leaves and shorter internodes characteristic of var hyssopifolia. The leaves in this variation are linear, 1-nerved, and 1.5-3 cm × 1-2.5 mm. The stems may be glabrous or show lines of puberulence or may be slightly puberulent, while the leaves are usually glabrous on the surface below with mostly hispidulous-aculeate midrib beneath and scabridulous margins. Although the resemblances of this variation appear to be more strongly developed towards typical var hyssopifolia and its forma psiloclada, the stems are more elongated and less branched than in var hyssopifolia.