Espèces nouvelles dans le genre Dalbergia (Fabaceae, Papilionoideae) à Madagascar

Five new species of Dalbergia (Fabaceae, Papilionoideae) from Madagascar are described: D. gautieri, D. manongarivensis, D. masoalensis, D. occulta and D. pseudoviguieri. The affinities of the species are discussed and their distinctive features pointed out. D. gautieri is distinct by its narrowly oblanceolate or narrowly cordate leaflets. Dalbergia manongarivensis is a liane close to D. bojeri Drake differing by its leaves with more leaflets. D. pseudoviguieri is close to D. viguieri Bosser & R.Rabev., differing by its terminal inflorescences with pubescent axes and calyces. Dalbergia masoalensis is close to D. viguieri by its paucifoliolate leaves and small flowers, differing by the inflorescences of compound racemes and by the shape and nervation of the leaflets. Dalbergia occulta is distinct of all other Malagasy Dalbergia by its short inflorescence of compound racemes, each raceme hidden by a large bract.