Wild plants of Lupinus angustifolius avoid extinction in a drought year by production of seeds with coats that are impermeable to water, preventing germination of a large percentage of the seed in any given year. Domesticated cultivars of this species carry the recessive gene mollis, making the seed coat permeable to water and, in turn promoting good crop establishment in the year of sowing. A dominant microsatellite-anchored fragment length polymorphism candidate marker was identified as being tightly linked to mollis in a population of recombinant inbred lines derived from domesticated and wild-type parents. The candidate marker was excised from the gel, amplified by PCR, sequenced and extended beyond the SSR end of the original MseI-SSR fragment. Two single nucleotide polymorphisms were found within this extended sequence. Specific primers were designed to create a marker 209 bp long. PCR products of these primers run on a single strand conformation polymorphism gel resolved in a co-dominant fashion. This marker will be used in marker-assisted selection for mollis when introgressing wild material into lupin breeding programmes.