Hibiscadelphus stellatus H. Oppenheimer, Bustamente, & Perlman, sp. nov., a new, narrowly endemic species from West Maui, Hawaiian Islands is described, illustrated and its affinities and conservation status are discussed. It is currently known from three populations totaling 99 plants in Kaua`ula valley on leeward western Maui. It differs from H. wilderianus, its nearest congener, in its denser white or tan stellate pubescence on most parts; larger externally purple colored corollas that are 5-6.5 cm long; linear-subulate to lanceolate, acute to acuminate involucral bracts; globose-cuboid to ovoid capsules; and endocarp with scattered hairs.
Keywords: Hawaiian Islands; Hibiscadelphus; IUCN Red List; Malvaceae; Maui; conservation.