A redefinition of Gastonia and related genera (Araliaceae)

The six genera Gastonia, Tetraplasandra, Reynoldsia, Munroidendron, Peekeliopanax, and Indokingia form a natural complex distributed from East Africa to the Marquesas and the Hawaiian Islands. The characters which have been thought useful in distinguishing these genera are re-examined. The distinction between Gastonia and Tetraplasandra is redefined, emphasis being placed on the radiating stigmatic arms in the fruit rather than on pleiomery of the stamens. On this basis Tetraplasandra is confined to the Hawaiian group. The monotypic genera Peekeliopanax and Indokingia are reduced to synonymy under Gastonia, which thus comprises all species of the complex west of Samoa.