Une nouvelle espèce de Meryta J.R.Forst. & G.Forst. (Araliaceae) de l’archipel des Tuamotu en Polynésie française

A new species of Araliaceae, Meryta puruhi Butaud, J.Florence, Lowry & F.Tronchet, sp. nov., endemic to the raised atolls of Anaa and Niau in the Tuamotu archipelago, French Polynesia, is described. Based on floral and fruit morphology, it clearly belongs to Meryta sect. Meryta Harms, which has been circumscribed to include species whose female flowers and fruits are appressed at the base. It most closely resembles M. lanceolata J.R.Forst. & G.Forst. and M. raiateensis J.W.Moore from the Society archipelago, with which it shares a similar inflorescence structure and free, basally appressed ovaries. It can be distinguished by its leaf shape (obovate to spatulate in M. puruhi, sp. nov. vs lanceolate to oblong in M. lanceolata and M. raiateensis) and the number of carpels [(7-)8-11 in M. puruhi sp. nov. vs 4-6(-7) in the other species]. This new species, the sole representative of the genus in the Tuamotu group, is threatened in part of its range by urban development and by the disappearance of the single bird species that serves as a disseminator, and has been assessed as Endangered [EN] according to the IUCN Red List criteria.