Nouvelles espèces du genre Pyrostria (Rubiaceae, Vanguerieae) de Madagascar

Atalahy, A.M., F. Rakotonasolo, M. Rabarimanarivo, H.L.T. Ranarijaona & S.G. Razafimandimbison (2021). New species of the genus Pyrostria (Rubiaceae, Vanguerieae) from Madagascar. Candollea 76: 1–12. In French, English and French abstracts. In the course of a taxonomic revision of the genus Pyrostria Comm. ex Juss. (Rubiaceae, Vanguerieae) in Madagascar, we describe five new species endemic from the Island: Pyrostria ambohitantelensis Atalahy, Rakotonas. & Razafim., Pyrostria ambrensis Atalahy, Rakotonas. & Razafim., Pyrostria betsomangensis Atalahy, Rakotonas. & Razafim., Pyrostria coriacea Atalahy, Rakotonas. & Razafim. and Pyrostria longicorollata Atalahy, Rakotonas. & Razafim. Each new species is provided with line drawings, a discussion on its morphological affinities and a risk of extinction assessment based on the IUCN Red List criteria.