Cyanea hamatiflora subsp. hamatiflora is characterized by simple, alternate leaves that are oblanceolate to narrowly oblong, measuring 50–80 cm in length and 8–14 cm in width. The apex of each leaf is acute, with the upper surface either glabrous or sparsely pubescent and the lower surface pubescent, particularly along the midrib and veins. The leaf margins are minutely callose-denticulate, and the leaves are sessile without stipules. The inflorescences are axillary, consisting of 5–10 flowers with peduncles 15–30 mm long and pedicels 5–6 mm long. The hypanthium is obconical to obovoid, 12–30 mm long and 6–12 mm wide. The flowers are bisexual, with a 5-lobed calyx having narrowly oblong lobes 12–18 mm long and 3–4 mm wide. The magenta corolla is zygomorphic, 60–80 mm long and 6–11 mm wide, glabrous, with downward-curved lobes giving it a unilabiate appearance. The plant has five stamens, alternate with the corolla lobes, with a staminal column that can be either glabrous or pubescent at the base. The anthers are glabrous, with the lower two having apical tufts of white hairs, opening by longitudinal slits. The filaments are either distinct or connate, attached to the base of the corolla. The ovary is inferior and 2-celled, with axile ovule placentation. The stigma is 2-lobed and changes from nonreceptive to receptive as the style grows through the anther tube. The berries with persistent calyx lobes are purplish-red, ellipsoid to obovoid, 30–45 mm long, and 20–27 mm wide. The seeds are numerous, small, brown to black, smooth, and shiny, measuring 0.2–0.5(–2) mm long, with a straight, short to spatulate dicotyledonous embryo embedded in oily endosperm. It is found in wet forests at elevations between 1200-1400 meters.