Analysis of relationships among endemic Hawaiian hibiscus

Abstract

There are 9 taxa of endemic Hibiscus section Lilibiscus in the Hawaiian Islands putatively derived from a single colonizing ancestor. Three of these taxa are federally listed as endangered. In the two complete taxonomic treatments of this group based on morphology, there is disagreement over the names and numbers of species and subspecies. This study was undertaken to examine the genetic relationships of these plants in an effort to clarify species boundaries. Randomly amplified polymorphic DNA (RAPD) markers were used to assess variation within and among populations and species. RAPD analysis demonstrated that the four previously recognized red-flowered taxa were genetically distinct as well as morphologically distinct from each other, and the extent of differentiation in H. kokio subsp. kokio (H. kahilii) and H. kokio subsp. saintjohnianus supports their recognition as separate taxa from H. kokio. The RAPD data indicates that the four red-flowered taxa should be recognized by their previously used names, H. clayi, H. kahilii, H. kokio and H. saintjohnianus.