Révision du genre Ivodea Capuron (Rutaceae), endémique de Madagascar et de l’archipel des Comores

A taxonomic revision of genus Ivodea Capuron is presented in which 30 species are recognized, 27 endemic to Madagascar, 2 restricted to the Comoro Islands, and 1 occurring in both archipelagos. Seventeen species are described as new (I. acuminata Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. analalavensis Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I ankeranensis Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. antilahimenae Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. aymoniniana Rabarim., Rakoton., Phillipson, Lowry & M.Pignal sp. nov.; I. capuronii Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. delphinensis Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. macrocarpa Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. mahaboensis Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. mananarensis Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. mayottensis Labat & M.Pignal, sp. nov.; I. moheliensis M.Pignal & Labat, sp. nov.; I. occidentalis Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. petrae Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. ravelonarivoi Rabarim., Rakoton., Phillipson & Lowry, sp. nov.; I. razakamalalae Rabarim., Rakoton., Phillipson & Lowry, sp. nov. and I. toliarensis Rabarim., Rakoton., Phillipson & Lowry, sp. nov.), one new combination is made (I. decaryana (H. Perrier) Rabarim., Rakoton., Phillipson & Lowry, comb. nov.), and one variety is raised to the rank of species (I. lanceolata (Capuron) Rabarim., Rakoton., Phillipson & Lowry, comb. et stat. nov.). Members of the genus are distinguished from one another by characters of the leaf blade (principally size, shape, texture and venation) and petiole (presence/absence of an articulation and of wings), the type of indument on various organs, the size and position of the inflorescence and infructescence, and features of the fruit surface. A key to the species is provided in French and English, along with distribution maps, a preliminary assessment of the conservation status of each species, and line drawings of each of the newly described entities.