This species varies morphologically across its range and locally. Steyermark separated var. grandiflora, with acute calyx lobes and glabrous leaves and petioles, from var. latifolia Steyerm. of Venezuela, with rounded calyx lobes and pubescent leaves and petioles; however glabrous and pubescent plants are found sympatrically in this region and the shape of the calyx lobes varies continuously, thus this variety is no loner separated.