Phylogenetic Relationships among Chilean Sophora Species

Abstract

Phylogenetic affinities among Chilean Sophora species are not clear. We sugge$t a new hypothesis for the origin of the section Edwardsia on the basis of parsimony analysis, which allows a South American origin to be e$tablishad for the species of this section. The seed alkaloid composition did not provide useful infonnation for the filiation of Edwardsia species, and the shortest tree was obtained using morphological charaeters only. Two branches are clearly distinguishable by the pubescence of the leaflets and the flag/wings length ratio: one of them ¡ncludes S. chrysophylla, S. tetraptera, S. toromiro, S. howinsula and S. denudata; the other one ¡ncludes S. macnabiana, S. mierophylla, S. masafuerana, S. prostrata and S. fernandeziana. In contrast, S. macrocarpa, an ancient element of the South American flora, is closely relatad to species belonging to the section Sophora representad in the region by S. tomentosa, S. linearifolia and S. rhynchocarpa. Sections Calia and Styphnolobium are clearly relatad to each other, both morphologically and chemically.