Nickrent & al. Classification of Santalales TAXON 59 (2) April 2010: 538558 TAXONOMY A revised classification of Santalales Daniel L. Nickrent,1 Valéry Malécot,2 Romina Vidal-Russell3 & Joshua P. Der4 1 Department of Plant Biology, Southern Illinois University, 1125 Lincoln Drive, CarBondale, Illinois 62901-6509, U.S.A. 2 UMR1259 GenHort, AGROCAMPUS OUEST Centre dAngers / Institut National dHorticulture et de Paysage, INRA, Univ-Angers, 2 rue Le Nôtre, 49045 Angers, France 3 LaBoratorio Ecotono, CONICET - Universidad Nacional del Comahue, Quintral 1250, (8400) Bariloche, Argentina 4 Department of Biology, Utah State University, 5305 Old Main Hill, Logan, Utah 84322, U.S.A. Author for correspondence: Daniel L. Nickrent,
[email protected] Abstract We present here a revised classification of Santalales, an angiosperm order that contains 18 families, 160 genera, and over 2200 species. Both nonparasitic and parasitic flowering plants occur in the traditionally circumscribed family Olacaceae whereas all other families are composed entirely of parasites. The five evolutionary radiations of aerial parasitism produced mistletoes that constitute most of the generic and specific diversity seen in the order. This classification, although based primarily upon results from molecular phylogenetic investigations, brings together all currently available information that contributes to our understanding of relationships among these plants. Monophyletic groups (clades) obtained from molecular analyses were named using a Linnaean ranked system. Four new families are named that formerly resided in Santalaceae s.l.: Amphorogynaceae, Cervantesiaceae, Comandraceae, and Nanodeaceae. A new tribal and subtribal classification for Loran- thaceae is presented where nine new subtribe names are proposed. Keywords classification; mistletoe; monophyletic; parasitic plant; sandalwood order INTRODUCTION of various families and genera of Santalales were published in the late 1890s by Tieghem (e.g., 1895a, 1896, 1897, 1899a).