Clermontia peleana subsp. singuliflora typically grows as epiphytic shrubs or trees, characterized by repeatedly branched, spreading stems that are light gray or light brown. These stems may be glabrous or rarely pubescent and are notable for their helically arranged leaf scars near the apex, solid pith, and white, dense latex. The plant has simple, alternate leaves with blades measuring 10–14 cm in length and 3.5–5 cm in width. The apex of the leaves is either acute or acuminate, with a cuneate base, green lower surfaces, and callose-crenulate margins. The petioles are 3–5 cm long, and the plant does not have stipules. The flowers are unique in their structure and form. They are bisexual, epigynous, zygomorphic (bilaterally symmetric), and resupinate, with a protandrous nature. The hypanthium is hemispheric or obconic, glabrous, and measures 1–1.5 cm in length and diameter. The calyx lobes are triangular, with an acute or acuminate apex. The corolla is unilabiate, green or greenish-white, and dull, measuring 5–5.5 cm long with a tube diameter of 0.8–1.2 cm. The plant has five syngenesious stamens with a strongly exserted, erect, or suberect staminal column. The anthers are connate, dithecal, and open introrsely by longitudinal slits. The pollen is tricolporate and prolate. The ovary is inferior, 2-carpellate, and 2-loculed with axile ovule placentation. The style is slender and terete, with a ring of stiff white hairs near the apex. The stigma is 2-lobed, with the lobes becoming receptive after pushing out pollen. The seeds are numerous, tiny, dark brown or black, minutely foveate-reticulate, and shiny. They contain a straight, short, spatulate dicotyledonous embryo embedded in oily endosperm. It is found in montane rainforests at an elevation of approximately 880 m.