Description of Taraxacum vansoestii Hagendijk, Oosterveld et Zevenbergen, spec. nov. The species is only known from the island of Terschelling, the Netherlands, out of the transition zone from sand dunes to saltmarsh. The taxonomic position of the new species, which shows affinities to quite different sections of the genus Taraxacum (viz. sect. Obliqua. \ sect. . Erythrosperma,: sect. Palustria and sect. Vulgaria) is discussed. The authors give arguments for a possible position in the group Dissimilia of the section Erythrosperma.