Chemical Diversity of Podocarpaceae in New Caledonia: Essential Oils from Leaves of Dacrydium, Falcatifolium, and Acmopyle Species by Nicolas Lebouvier* a ), Leïla Lesaffre a ) b ), Edouard Hnawia a ), Christine GouØ a ) b ), Chantal Menut b ), and Mohammed Nour a ) a ) Laboratoire Insulaire du Vivant et de l)Environnement (LIVE) -EA 4243-, UniversitØ de la Nouvelle- CalØdonie, BP R4, 98851 NoumØa Cedex, Nouvelle-CalØdonie (e-mail: nicolas.lebouvier@univ-nc.nc) b ) Equipe glycochimie, IBMM-UMR 5247 CNRS-UM, 15 avenue Charles Flahault, BP 14491, FR-34093 Montpellier Cedex 5 Plant secondary metabolites can be useful chemosystematic markers to distinguish species at different taxonomy levels. For example, sesquiterpenes and diterpenes show specific distribution patterns within conifers and so provide especially precious information about the diversity and evolutionary relationships of this group. The aim of the present study was to provide a first insight into the terpene diversity of endemic Podocarpaceae from New Caledonia. The leaf essential oils of Dacrydium araucarioides Brongn. & Gris, Dacrydium balansae Brongn. & Gris, Dacrydium guillauminii J.Buch- holz, Dacrydium lycopodioides Brongn. & Gris, Falcatifolium taxoides ( Brongn. & Gris) de Laub., and Acmopyle pancheri ( Brongn. & Gris ) Pilg. from New Caledonia were characterized by GC/FID and GC/MS analyses, and the chemotaxonomic relationships of these species were determined by comparison of their terpene compositions. Cluster analysis based on the biosynthetic origin of their volatile terpenes led to the description of three distinct groups of essential oils and showed close relationships between those of D. araucarioides and D. balansae as well as between those of A. pancheri and F. taxoides . Introduction. – The Podocarpaceae are an ancient family of conifers of Gondwanan origin, dating to the Triassic – Jurassic period. The family comprises 18 genera and 173 species, essentially distributed in tropical and subtropical regions of the southern hemisphere [1]. Its genus richness is higher in the Malesian region and in New Caledonia, where a distinctive conifer flora has evolved on account of its geological history and its isolation in the southwestern Pacific Ocean. The 20 endemic species of Podocarpaceae in New Caledonia belong to eight genera: Podocarpus , Dacrydium, Retrophyllum, Falcatifolium, Dacrycarpus , Acmopyle, Prumnopitys , and Parasitaxus [2][3]. Recent attention has been paid to the Podocarpaceae family, which has been studied at the species level on the basis of molecular, biogeographical, morphological, and anatomical data [4] [5]. Analyses of the anatomy, embryology, and chemistry allowed the classification of the Podocarpaceae by proposing two groups for this family: Podocarpus sensu latissimo (sl ) and Dacrydium sl, each including several subsections [6]. An analysis of the family based on rbcL (ribulose bisphosphate carboxylase large chain) sequences helped to identify three major clades: Podocarpoid, Dacrydioid, and Prumnopityoid [7]. More recently, the study of Knopf et al. [5], also based on the analysis of rbcL sequences, classified the species of the Dacrydium group in two subclades: the Melanesian subclade and the New Caledonian subclade, CHEMISTRY & BIODIVERSITY – Vol. 12 (2015) 1848 # 2015 Verlag Helvetica Chimica Acta AG, Zürich