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