Lessons from Plectocephalus (Compositae, Cardueae-Centaureinae): ITS disorientation in annuals and Beringian dispersal as revealed by molecular analyses

Abstract

The natural status of the genus Plectocephalus is confirmed and several nomenclatural combinations are proposed. New evidence contributes to the debate concerning problems posed by the use of ITS in the phylogenetic reconstruction of groups that differ in terms of their life cycles. Dispersal from Caucasus and Anatolia along the Siberian route and then across the Bering Land Bridge follows a route previously proposed for other taxonomic groups.

A test of Darwin's naturalization hypothesis in the thistle tribe shows that close relatives make bad neighbors

“…The Bayesian consensus tree in Fig. 1 illustrates the phylogenetic distribution of species of the four possible biogeographic and ecological categories used in this study (invasive, noninvasive exotic, native, and not present in CAFP), and is largely congruent with previous studies, including the paraphyly of subtribe Carduinae and strong support for the monophyly of Centaureinae as traditionally circumscribed (80,83). Nonnative (introduced) species were classified as either invasive or noninvasive based on the California Invasive Plant Council invasive plant inventory (84).…”

“…Sampling was based on previous systematics studies (80,83,101) to represent most of the genera and major clades of the tribe Cardueae. Plant material was collected both from the field and herbarium specimens.…”

Phylogenetic insights into Andean plant diversification

“…The diversification of this group in the Atacama Desert during the Pliocene, isolated on the western slope of the Andes, was probably facilitated by Andean uplift and the subsequent development of aridity (Sepulchre et al, 2009). This scenario was also suggested for the origin of monotypic Gypothamnium (Asteraceae) in the Atacama Desert ) and for Plectocephalus in South America (Asteraceae; Susanna et al, 2011). On the south-eastern side of the Andes, the onset of diversification of Heliotropium sect.…”

Sesquiterpenoids in subtribe Centaureinae (Cass.) Dumort (tribe Cardueae, Asteraceae): Distribution, 13C NMR spectral data and biological properties

“…This group is always placed in a basal position, far removed from the bulk of the genus . A recent survey of Centaureinae and Plectocephalus (Susanna et al, 2011), based on nuclear internal transcribed spacers (ITS) analyses, identified Stizolophus and Zoegea as sisters to the rest of this group.…”