Phylogeny and classification of Carex section Ovales (Cyperaceae)
AbstractSection Ovales is the most species-rich section of the sedge genus Carex in the New World. Phylogenetic analyses of molecular data recover a predominantly New World clade as sister to a solitary east Asian species, C. maackii. Nuclear ribosomal DNA are congruent in the placement of all taxa within the section, with a solitary exception: incongruence between ITS and ETS data in the placement of C. bonplandii and C. roraimensis suggests a hybrid origin for this lineage. Biogeography correlates strongly with phylogeny in the section, but there have been at least two instances of long-range dispersal, one from an eastern North American clade to western North America and one from the New World to Eurasia. Morphological characters studied are all homoplastic. Developing a comprehensive infrasectional classification with a phylogenetic basis would be complicated by the fact that most of the novel morphological characters in the section have evolved within relatively small, independent clades.
Volume, Issue, Page Number167, 5, 1029-1048