Palynological study of Veronica Sect. Veronica and Sect. Veronicastrum (Scrophulariaceae) and its taxonomic significance

Pollen grains from 30 taxa, mainly from the Western Mediterranean area belo nging to the perennial sections of the genus Veronica (Scrophulariaceae), w ere studied by LM and SEM. A close relationship was found between pollen si ze and ploidy level. Palynological characters cannot be regarded as essenti al taxonomic tools within the groups studied, although they have systematic value in some specific cases. The monophyly of Veronica subsect. Multiflor ae is supported by a common and exclusive sculpture of exine. Delimitation of the genus is discussed and hypothetical evolutionary trends concerning p ollen characters are addressed.