Alpinia spongioides (Zingiberaceae), a new species from Dinagat Islands, Philippines

Alpinia spongioides Naive, Ruales, Beltran & Rozano, is described here as a new species from Dinagat Islands, Philippines. The species belongs to Alpinia sect. Alpinia subsect. Presleia by having small flowers and quadrilobed labellum. It resembles Alpinia foxworthyi but differs by its puberulent ligule with ciliate margin, longer petiole, calyx, filament, as well as an ecristate anther. This paper provides a detailed description, colour plates, and information on its phenology, habitat and distribution, as well as a provisional conservation status assessment. The discovery of this species through recent botanical surveys in eastern Mindanao brings the total number of known Alpinia subsect. Presleia species in the Philippines to 15.