Lysimachia minoricensis is a Mediterranean (Balearic Islands) endemic that is extinct in the wild but extant in botanical gardens. Previously, no variation at 22 isozyme loci was revealed in more than 150 analysed plants. Random amplified polymorphic DNA (RAPD) analysis was used to examine genetic variation among five individuals from each of eight botanical garden accessions (40 plants). No polymorphisms were detected at 201 amplified bands. This is the first report of RAPD monomorphism in a nonapomictic vascular plant. The lack of detectable genetic variation suggests that an extremely reduced gene pool was recovered in the field before its extinction. Although the screening of other genomic markers is feasible, it is suggested that the knowledge of biological and autoecological features should be prioritized before new re-introductions are attempted.