[P caumii F. Brown; P. hawaiiensis Degener; P. pilosa L. subsp. villosa (Cham.) Gees.]
(end, V) ‘Ihi
Perennial herbs from a fleshy, tuberous, but becoming woody taproot; stems prostrate to weakly ascending, up to ca. 3 dm long. Leaves pale grayish green, narrowly oblanceolate to linear, subterete, 5-25 mm long, 1.5-3 mm wide, sessile, with a dense tuft of yellowish brown hairs (1—)3—12 mm long in the axil. Flowers usually 3-6 in dense, terminal, head-like cymes subtended by dense tufts of hairs 6-12 mm long and a series of involucrate leaves, bracteoles ca. 1.4-1.5 mm long; sepals 4-5 mm long, margins scarious; petals white, pink, or pink with a white base, obovate, 8-10 mm long, apex emarginate; stamens 18-50; style 5- 7(8)-branched. Capsules broadly ovoid, 3-5 mm long, the walls thin, ca. 0.05 mm thick, circumscissile near base up to lA from base. Seeds dark reddish brown, 0.6-0.7 mm long, the surface stellulate-rugulose. Occurring on dry, rocky, clay, lava, or coralline reef sites, 0-300(-490) m, on Nihoa, Ka- ‘ula, and documented from all of the main islands except Ni‘ihau and Kaua‘i.—Plate 154.
A single population of erect subshrubs with green, linear-subulate leaves 10-20 mm long and 1-2 mm wide, with a tuft of dingy white hairs 1-1.5 mm long in the axil, white emarginate petals ca. 10 mm long, ca. 14 stamens, and 3-branched styles, from west of Olowalu, ca. 120 m, Maui, which would key to Portulaca villosa in this treatment, may actually represent a recently naturalized species. However, it more likely represents an undescribed endemic taxon.