Lagourgue L. auteur aut IRD Puillandre N. auteur aut IRD Payri Claude auteur aut IRD text journalArticle eng text/pdf born digital access The Udoteaceae family (Bryopsidales, Chlorophyta) is known to be highly diverse morphologically in the Caribbean region, but only few studies have studied its genetic diversity. Using an integrative taxonomic approach, this study aimed at (1) exploring the Udoteaceae species diversity using a combination of five DNA-based species delimitation methods and morpho-anatomical data for confirmation; (2) estimating the discriminatory power of traditional diagnostic characters using a morphology-based clustering method and statistical analyses focused on the genus Udotea; and (3) reconstructing the phylogeny of the family based on a multilocus analysis (tufA, rbcL, 18S rDNA). Our results revealed strong congruence between species hypotheses across delimitation methods and markers. Morpho-anatomical characters proved essential to validate these hypotheses, to assign species names and to unveil new species. Morphological analyses led to relevant results for accurately discriminating Udotea morphospecies. Siphon features and cortication were key characters to define supra-specific groups and to revise the taxonomy of the genus Udotea. Phylogenetic analyses confirmed the polyphyly of Udotea, Rhipocephalus and Penicillus, which led us to propose a revised definition of Udotea sensu stricto based on both genetic and morphological data. Finally, our study emphasizes the importance of combining genetic and morphological data for the taxonomic revision of the Udoteaceae, but stresses the need of including more taxa from other geographical regions to better resolve taxonomic issues. specialized Bryopsidales Udoteaceae Udotea Species delimitation Multilocus phylogeny Morphological clustering CARAIBE ZONE TROPICALE 034 127 758-769 2018 1055-7903 https://www.documentation.ird.fr/hor/fdi:010074522 10.1016/j.ympev.2018.06.023 1055-7903 [F B010074522] https://www.documentation.ird.fr/hor/fdi:010074522 https://www.documentation.ird.fr/intranet/publi/2018/12/010074522.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2019-01-10 2023-07-11 fdi:010074522 fre