Clermontia peleana of the Campanulaceae (bellflower) family is an epiphytic shrub or tree 1.5 to 6 m (5 to 20 ft) tall which grows on Metrosideros spp. (ohia), Acacia koa (koa), Cheirodendron trigynum (olapa), and Sadleria spp. (amau). The alternate, stalked, oblong or oval, toothed leaves reach a length of 8 to 20 cm (3 to 8 in) and a width of 3 to 5 cm (1.2 to 2 in). Flowers are single or paired, each on a stalk 3 to 4.5 cm (1.2 to 1.8 in) long with a main stalk 0.8 to 1.7 cm (0.3 to 0.7 in) long. Five small green calyx lobes top the hypanthium (basal portion of the flower). The blackish-purple (ssp. peleana) or greenish-white (ssp. singuliflora) petals 5 to 7 cm (2 to 2.8 in) long and 0.8 to 1.3 cm (0.3 to 0.5 in) wide, are fused into a one-lipped, arching tube with five down-curved lobes. Berries of ssp. peleana are orange and 2.5 to 3 cm (1 to 1.2 in) in diameter.