Cyanea pilosa subsp. longipedunculata is a shrub ranging from 0.8 to 2 meters in height. The stems are sub-herbaceous and woody only at the base, typically unbranched or occasionally sparingly branched from the base, and are pubescent throughout. The leaves are simple and alternate, with broadly elliptic to broadly obovate blades measuring 15–42 cm in length and 8–15 cm in width. The leaf apex is acuminate, and the base ranges from rounded to cuneate. The upper surfaces of the leaves are green and pubescent, while the lower surfaces are whitish green and densely pubescent. Leaf margins are erose. Petioles are 3–9 cm long, and stipules are absent. The flowers are perfect (bisexual) and arranged in 12–28-flowered inflorescences that are 70–180 mm long and pubescent. The pedicels are 5–10 mm long. The hypanthium is obovoid and measures 4–6 mm in length. The calyx has narrowly triangular lobes 2–5 mm long with acuminate apices. The corolla is white with tinges or streaks of purple, 20–28 mm long and 3–4 mm wide, glabrous, with a suberect to gently curved tube and spreading lobes that are ¼ to ⅓ as long as the tube. There are five stamens, which alternate with the corolla lobes and are connate into a white staminal column that is pubescent toward its apex. The anthers are white and pubescent, with the lower two bearing apical tufts of white hairs. The ovary is inferior and 2-celled with axile ovule placentation. The stigma is 2-lobed and initially appressed and non-receptive, while the style pushes through the anther tube. The fruit is an orange berry, globose to ellipsoid in shape, 7–10 mm long, and crowned by persistent calyx lobes. Seeds are numerous. It is found in wet forest habitats across the Kohala Mountains, windward Mauna Kea, and windward Mauna Loa on Hawaiʻi Island, between 610-1,300 meters.