Phylogeny of Echiochilon (Echiochileae, Boraginaceae) based on ITS sequences and morphology

A phylogenetic analysis of Echiochilon and representatives of Antiphytum and Ogastemma based on nuclear internal transcribed spacer (ITS) sequences of the ribosomal DNA indicated that zygomorphy is the plesiomorphic condition in Echiochilon. Antiphytum and Ogastemma were resolved as sister taxa, together forming the sister group to Echiochilon. An analysis based on morphological data mainly corroborates the ITS phylogeny, with a notable exception concerning the position of the actinomorphic-flowered E. johnstonii. Biogeographic interpretation of the ITS phylogeny using DIVA (dispersal vicariance analysis) indicated an ancestor to Echiochilon with a wide distribution over northern Africa and Arabia to India.