A Taxonomic Revision of the Endemic Hawaiian Lysimachia (Primulaceae) Including Three New Species

Abstract

A taxonomic revision of the endemic Lysimachia of the Hawaiian Islands was undertaken with the goal of clarifying species boundaries, especially within the L. hillebrandii/L. remyi complex of the previous taxonomic treatment. The endemic species appear to be monophyletic with Malesian affinities. The revision presented here is based upon observations of morphological characters. Sixteen species are recognized, of which three are probably extinct. Most species have narrow ecological preferences and are endemic to a single island. Species differ from each other most notably in the size, shape, and venation of the leaves; the size, shape, and pigmentation of the calyx and corolla lobes; and the presence or absence of viscid stems and leaves. Populations previously classified within L. hillebrandii or L. remyi differ in a number of characters not previously evaluated including vestiture, leaf color and venation, pedicel position and color, and calyx shape and color. Three new species, L. iniki, L. pendens, and L. scopulensis, are described. A key to species, species descriptions, and distribution maps are provided.