Monographs Details: Siphanthera cordifolia (Benth.) Gleason
Authority: Maguire, Bassett & Wurdack, John J. 1958. The botany of the Guayana Highland--Part III. Mem. New York Bot. Gard. 10: 1-156.

S. jenmani Gleason, Brittonia 1: 137. 1932.

S. cordifolia (Benth.) Gleason var. glomcrata Gleason, Fieldiana Bot. 28: 426. 1952.

I have now seen 25 collections of this complex and believe that Jenman 1039, Sandwith 1345, and Maguire & Fanshawe 23161 represent ± glabrous ± eglandular collections of the more typically hairy and glandular 8. cordifolia: intermediate are such collections as Tale 1131, Tale 341, and Steyermark 59345, with Steyermark & Wurdack 448 showing extreme variability within one population. Var. glomerata is almost the same as the type of var. cordifolia; such glomerateheaded plants occur randomly in populations of S. cordifolia and probably are pathologic in origin. Indeed specimens with relatively lax inflorescences are more different in appearance from Schomburgk 1062 than is Steyermark 59397. There seem to be no critical floral features for any varietal differentiation. Perhaps the most distinct collection of the complex is Schultes & Cabrera 14359 (NY) from Cerro Yapoboda, Vaupes, Colombia; the leaves have much more distinct petioles and the leaf bases are only rounded rather than cordulate. Otherwise the Colombian collection is S. cordifolia from the glabrous end of the specific spectrum.