title: Molecular phylogeny and systematics of the highly polymorphic Rumex bucephalophorus complex (Polygonaceae).
abstract: Rumex bucephalophorus is a very polymorphic species that has been subjected to various taxonomic studies in which diverse infraspecific taxa have been recognised on the basis of diaspore traits. In this study we used molecular markers (ITS and AFLP) to explore this remarkable diversity, to test previous hypotheses of classification, and attempt to explain biogeographic patterns. Results show that R. bucephalophorus forms a monophyletic group in which diversification began around 4.2 Mya, at the end of Messinian Salinity Crisis. The two molecular markers clearly show a deep divergence separating subsp. bucephalophorus from all other subspecific taxa, among which subsp. canariensis also constitutes a separate and well distinguishable unit. In contrast, subspecies hispanicus and subsp. gallicus constitute a monophyletic group in which three subgroups can be recognised: subsp. hispanicus, subsp. gallicus var. gallicus and subsp. gallicus var. subaegeus. However, these three subgroups are not clearly distinguished genetically or morphologically, so that in formal classification it would be preferable to treat them at the varietal level.
authors.affiliation: Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, Apdo 1095, 41080 Sevilla, Spain. mtalavera@us.es
authors.forename: M
authors.initials: M
authors.lastname: Talavera
authors.forename: F
authors.initials: F
authors.lastname: Balao
authors.forename: R
authors.initials: R
authors.lastname: Casimiro-Soriguer
authors.forename: M Á
authors.initials: MÁ
authors.lastname: Ortiz
authors.forename: A
authors.initials: A
authors.lastname: Terrab
authors.forename: M
authors.initials: M
authors.lastname: Arista
authors.forename: P L
authors.initials: PL
authors.lastname: Ortiz
authors.forename: T F
authors.initials: TF
authors.lastname: Stuessy
authors.forename: S
authors.initials: S
authors.lastname: Talavera
mesh_terms: D054458:Amplified Fragment Length Polymorphism Analysis; D001499:Bayes Theorem; D002467:Cell Nucleus / Q000235:genetics; D002965:Classification; D016000:Cluster Analysis; D021901:DNA, Intergenic / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D005828:Genetics, Population; D005843:Geography; D008969:Molecular Sequence Data; D009018:Morocco; D010802:Phylogeny; D011110:Polymorphism, Genetic; D025341:Principal Component Analysis; D031804:Rumex / Q000145:classification* / Q000235:genetics*; D058614:Seed Dispersal / Q000235:genetics; D013030:Spain
chemical_list: D021901:DNA, Intergenic; D018744:DNA, Plant