XVI International Botanical Congess

In 1959, Lewis and Epling proposed Delphinium gypsophilum as a hybrid species derived from D. hesperium and D. recurvatum. Delphinium gypsophilum has since been considered a classic example of hybrid speciation. We tested the putative hybrid origin of D. gypsophilum using population-level and phylogenetic analyses of D. gypsophilum, its putative parents, and close relatives using molecular data. Allozyme analyses of multiple populations do not support the hybrid origin of D. gypsophilum, however data from several loci are equivocal, and more sensative markers are needed. AFLP markers are being used to test the hypothesis of hybrid origin further. Phylogenetic analyses of the 67 species of Delphinium section Diedropetala based on ITS sequences suggest that D. gypsophilum is not of hybrid origin.