Intraspecific differentiation of Limonium wrightii (Plumbaginaceae) on northwestern Pacific Islands: Rate heterogeneity in nuclear rDNA and its distance-independent geographic structure

We conducted a molecular phylogenetic analysis of a coastal sea lavender in NW Pacific using ITS sequences of nrDNA. As a result, the ITS sequences of populations on the oceanic Daito Islands were considerably different from conspecific others in nine apomorphic substitutions. This finding indicates a distance-independent geographical structure of the genetic variation among islands in NW Pacific. The calibrated rate of nucleotide substitutions in the ITS regions within L. wrightii (average: 1.41 × 10−8 substitutions per site per year) was higher than any other instances of substitution rates in flowering plants.