Abstract
The Senecio matatini complex in New Zealand has a convoluted taxonomic and nomenclatural history that has not been fully resolved. This is largely due to the incomplete sampling of morphologically diverse but highly threatened limestone populations in the eastern South Island in previous genetic studies. In this study, we have included six informally recognised limestone entities, together with the four subspecies of S. matatini , into analyses of a reduced‐representation restriction‐site associated DNA sequencing (RAD‐seq) (genotyping by sequencing) dataset comprising 4,457 single‐nucleotide polymorphisms from 75 samples. sNMF LEA, PCA, and SplitsTree analyses of this dataset distinguished several discrete metapopulation lineages. Based on these results, we present a revised taxonomic classification that restricts S. matatini to populations in northwest Nelson. In addition, two previously recognised subspecies of S. matatini are elevated to species rank, while a third is reassigned as a subspecies of S. basinudus . We also recognise several metapopulations from limestone habitats as taxonomic novelties at the rank of subspecies and species. The three new combinations are S. toa , S. basinudus and S. basinudus subsp. discoideus and the four newly recognised taxa are S. basinudus subsp. tenuis , S. toa subsp. complanatus , S. toa subsp. pectinatifolius and S. vegrandis .