Phyletic Trends in Section Coreopsis of the Genus Coreopsis (Compositae)

Publisher Website
Google Scholar
Abstract
Artificial hybridization, fertility of interspecific hybrids, chromosome numbers and trends in habit and morphology in taxa of section Coreopsis of the genus Coreopsis are used to derive a presumed phylogeny for the section. The perennials in the section are relatively primitive and rather closely related to each other, while the annuals are relatively advanced and not closely related to the perennials. The annual species consist of 2 pairs of species; the pairs are not closely related, but the 2 members of each pair are closely connected in a progenitor-derivative relationship. Chromosome evolution in the section has involved descending aneuploidy in 2 of the annuals and polyploidy in 1 perennial.