The genus Dicksonia (Dicksoniaceae - Cyatheales) in western Malesia

Abstract

We present an update of the taxonomy of the challenging genus Dicksonia in Malesia excluding New Guinea with its directly adjacent islands. The species D. blumei and D. mollis are maintained and additional distinguishing characters are given. As here defined their ranges do not overlap, with D. blumei present on Sumatra, Java and Bali, and D. mollis on Borneo and the Philippines. On Mindanao, D. mollis is sympatric with a newly recognized species, D. amorosoana sp. nov. On Sulawesi, there is only one species confirmed, D. celebica sp. nov. All these morphological separations are supported by molecular data. Also present in the area are D. timorensis, occurring only on Timor and more closely related to D. antarctica from southern Australia than to the rest of the Malesian taxa, and D. ceramica sp. nov., endemic to Seram Island and with strong affinity to the New Guinean D. lanigera and D. hieronymi. Lectotypes are chosen for D. blumei and Balantium chrysotrichum. Descriptions and a key for all species in the study area are provided.