Description

Key Characters:

Growth Form: Plants 0.6–1.5 m tall.

Stems: Stem 0.8–1.4 cm diam. glabrous, cicatrices shallowly obtriangular, 1–2 mm tall, 3.5–5 mm wide.

Roots: Roots mycotrophic via vesiculararbuscular mycorrhizae (Koske et al. 1992).

Leaves: Leaves simple. Alternate, forming a dense spherical, oblate, or cylindrical apical rosette. Blades narrowly elliptic, 12–16×1.1–1.5 cm, 10–13 times longer than wide. Apex acuminate. Base attenuate, sometimes quite petiole-like, in other cases the differentiation of a petiole very indefinite and the leaf clearly sessile. Surfaces glabrous; blades coriaceous. Margins entire. Stipules absent.

Flowers: Flowers in raceme terminal, single, erect, 13–65–flowered, glabrous; peduncle 15–27 cm long; sterile bracts lanceolate, narrowly elliptic, narrowly oblong, or linear, 17–120×4–15 mm, the margin entire, the apex acuminate; rachis 10–29 cm long; floral bracts lanceolate or linear, 11–26×2.8–4 mm, the margin entire, the apex acuminate; pedicels 22–30 mm long; bracteoles ovate or broadly elliptic, 1.5–3 mm long; hypanthium ovoid or oblate, 5–7 mm long, 5.5–7 mm diam. 1/14–1/10 as long as the corolla. Flowers tetracyclic, bisexual (perfect), protandrous, zygomorphic, epigynous, pedicellate, resupinate, ornithophilous, large. Calyx lobes triangular, ovate, lanceolate, or oblong, erect, 4–6×2–3 mm, ⅗ as long as to equaling the hypanthium, the margin entire, the apex obtuse. Corolla subbilabiate, bright crimson, 45–52 mm long; tube gently curved, 27–33 mm long, 6–8 mm tall at middle, 3–7 mm tall at mouth, 3.8–5.5 times longer than height at middle; dorsal lobes 18–24×1.5–2.5 mm, ½–¾ as long as the tube, the apex acuminate; ventral lip obovate, 14–18×6–10 mm. Stamens 5, antisepalous, connate distally for most of their length; Staminal column scarcely exserted, emerging above or between the dorsal lobes; filament tube 37–42 mm long, 3.1–3.8 times longer than dorsal anthers, pubescent toward the apex; anther tube 3.2–4 mm diam. pubescent toward base; dorsal anthers 10–12 mm long; ventral anthers 8–9 mm long, with tufts of white trichomes 1.5–2 mm long at apex. Pollen grains 41–44 μm polar diam. 27–30 μm equatorial diam. prolate, tricolporate, the exine shallowly and minutely reticulate (Selling, 1947). Ovary inferior, 2-loculed, adnate to the hypanthium, flat at apex; placentae axile; ovules numerous; style 1, slender, terete (cylindrical), with a ring of stiff white hairs near the apex; stigma 2-lobed, the lobes appressed and non–receptive as the style grows through the anther tube, pushing out pollen, after which the stigmas spread and become receptive.

Fruit: Capsules oblate; 8–9 mm long; 11–13 mm wide; 8–9 mm thick; the pores numerous; scattered over the entire lateral surface. Seeds unknown.

Ploidy: 2n = 28

Habitat: Endemic to the upper slopes of Kōnāhuanui in the southern Ko‘olau Mountains of O‘ahu; in lowland wet shrubland.

Elevation Range: 915–965 m.