Isnard Sandrine auteur aut IRD L'Huillier L. auteur aut IRD Rigault Frédéric auteur aut IRD Jaffré Tanguy auteur aut IRD text journalArticle eng text/pdf born digital access New Caledonia is renowned as one of the world's most significant biodiversity hotpots. The nutrient-deficiency and cations imbalances of ultramafic soils, which cover a third of the island, harbor a disproportionally high proportion of the plant diversity and endemism of New Caledonia. This review explores how ultramafic soils have influenced the exceptional endemism and richness of New Caledonia trough the concomitant occurrences of habitat patchiness, climatic instability, environmental gradient, and edaphic heterogeneity of ultramafic soils. We focus on the unique 'maquis' vegetation where selective pressures by nutrient deficiency and trace element surplus are at their acme. We aim to synthesize our current understanding of diversification and speciation of lineages that have been phylogenetically studied to date. Fragmentation of the peridotite mantle in isolated massifs, and as such spatial heterogeneity of ultramafic soils types, appear to promote plant endemism and speciation. Repeated independent dispersal events of pre-adapted species and persistence of paleo-endemic lineages have contributed to the phylogenetic diversity and the endemism of the ultramafic flora. Finally, historical climatic instability has caused shifts of rain forest species in refugia thereby favoring the extension of maquis species. specialized Diversification Endemism Forests Harsh edaphic conditions Maquis Nutritional strategies Preadaptation Species richness NOUVELLE CALEDONIE 082 068 076 403 1-2 53-76 2016 0032-079X https://www.documentation.ird.fr/hor/fdi:010066995 10.1007/s11104-016-2910-5 0032-079X [F B010066995] https://www.documentation.ird.fr/hor/fdi:010066995 https://www.documentation.ird.fr/intranet/publi/2016/07/010066995.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2016-08-01 2022-02-22 fdi:010066995 fre