Flora of the Hawaiian Islands
Dicotyledon Literature for Kadua haupuensis
Lorence et al., 2010.
   Rubiaceae -- The Coffee Family Bibliography
      Kadua haupuensis
General Information
DistributionIsolated to the Mt. Ha’upu region of Kaua’i. In the Hawaiian Islands, endemic to Kaua`i.

HabitatIn mesic forest on North face of Mt. Ha’upu
Subdioecious shrubs 1–1.5 m tall with erect, brittle stems, branchlets terete, glabrous except minutely puberulent at nodes, older branches with brown, longitudinally fissured bark.
Leaves with blade oblong-lanceolate to oblong-ovate, 3–11.5 x 0.7–3.2 cm, chartaceous, adaxially glabrous and lustrous, abaxially glabrous or sparsely hirtellous, more densely so on costa; secondary veins 3-6 pairs, festooned brochidodromous, tertiary veins conspicuously reticulate, weakly prominulous on both surfaces, translucent when fresh and visible to 4º; petioles 2–16 mm long, narrowly winged, glabrous or puberulent abaxially; stipules externally glabrous, with sheath 1.5–3 mm long, the awn 2–5 mm long.
Inflorescences (6–)10–67-flowered, cymose-paniculiform, dichasial, 2–4 x 2–4.5 cm, subtended by a pair of leaf-like bracts, the axes glabrous or glabrate, the primary branches 2–3 pairs, the monochasial ultimate branches each bearing 3–12 flowers, each subtended by a glabrous or sparsely puberulent, subulate to linear-oblong bract 2–8 mm long. Flowers with calyx 4-lobed, lobes linear-oblong to linear-oblanceolate, 2.5–6 x 0.3–0.8 mm, glabrous or margins ciliolate, erect-spreading, green with purple tint when fresh. Staminate flowers with hypanthium obconic, 1–1.5 mm long, glabrous; corolla tube 10–16 mm long, lobes 2.5–3.5 mm long, oblong-ovate to elliptic, style plus stigma 4–7.5(–12) mm long, about 2/3 the length of the tube, villous toward base, stigma slightly bilobed apically, 1–1.5 mm long, anthers 2–2.5 mm long, polleniferous, inserted 4 mm below top of tube. Pistillate flowers with hypanthium obconic, 1.5–2 mm long, glabrous; corolla tube 9–10 mm long, lobes 2–2.5 mm long, triangular-ovate, style plus stigma typically 6–11 mm long, villous toward base, stigma slightly bilobed apically, 3.5–4 mm long, swollen, papillose, stigma tips exserted from mouth of tube; anthers 1.2–1.3 mm long, abortive and non-polleniferous, inserted 3 mm below mouth of tube. Hermaphroditic flowers (occur sporadically on staminate plants) resemble staminate flowers in having larger, polleniferous anthers and short styles with stigmas included but apparently functional.
Capsules broadly obovoid, 3.5–4.5×4– 5 mm, glabrous, weakly bisulcate, weakly compressed laterally, weakly costate, calyx lobes persistent, spreading, apical portion of capsule 0.5–1 mm long, minutely puberulent, dehiscence initially loculicidal then tardily separating septicidally.
Seeds numerous, dark brown or blackish, 0.5–0.6×0.25–0.4 mm, irregularly obovate to ellipsoid, somewhat angulate, compressed laterally, surface papillose with prominent, bubble-like protuberances.
Nancy Khan