Schiedea napaliensis W. L. Wagner & Weller 2025, sp. nov.
Creators: name: Wagner, Warren L.
name: Weller, Stephen G.
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Caryophyllales
Caryophyllaceae
Schiedea
Schiedea napaliensis

description: Schiedea napaliensis W. L. Wagner & Weller sp. nov.
Figs 2, 3, 4
Type.
Hawaiian Islands, Kaua‘i • Mahanaloa Valley, up valley from old horse trail, S side of valley, [22°12'35.6"N, 159°34'27.2"W], 10 July 1991, S. Perlman & J. Obata 12074 (holotype: PTBG-1000046146!; isotypes: BISH, MO, US!).
Description.
Erect to ascending subshrubs 3–10 dm tall; stems few-branched, glabrous, becoming sparsely then moderately glandular-puberulent in the inflorescence, the internodes purple. Leaves opposite; blades 7.5–15 cm long, 1.8–4.1 cm wide, oblong-elliptic, light green or yellowish green, adaxial surface slightly glossy, the abaxial surface glossy, slightly thickened and rubbery, chartaceous when dry, usually slightly undulate, with only the midvein evident or sometimes with an additional pair of inconspicuous, smaller, looping veins, the midvein ± slightly excentric, margin entire, slightly thickened and weakly revolute, especially toward the base, apex acute to weakly acuminate, base gradually attenuate; petioles 0.5–1.1 cm long, pale green, purple toward the base, weakly ± grooved. Inflorescence terminal, with 27–70 flowers, 20–48 cm long, diffuse, flowers widely spaced, branches spreading, progressively more densely puberulent to apex, the hairs straight, erect, 0.1–0.35 mm long; bracts subulate, the lowermost of the central axis elliptic-lanceolate, as green as the leaves, recurved and often twisted, the lower ones 30–45 mm long, those of the branches and flowers 5–18 mm long; pedicels (7 –) 10–23 mm long, elongating slightly in fruit, slightly asymmetrically flattened. Flowers hermaphroditic. Sepals 4.3–4.8 mm long, lanceolate, green, opaque, strongly reflexed and convex in the proximal 1 / 4, producing a small transverse bulge, the distal part shallowly concave, oriented ca. 40 ° to 80 ° angle to the pedicel, glandular-puberulent, a few of the hairs sometimes non-glandular, margins scarious, ciliate, apex long-attenuate. Nectary base 0.6–0.9 mm long, dark yellow, the nectary shaft 3–4.5 mm long, gently recurved, at 90 ° to the axis, apex deeply bifid, sometimes divided nearly to the base. Stamens 10; filaments dimorphic, the antisepalous whorl 7.5 mm long, the alternate whorl 5.3–5.8 mm long; anthers 0.75–0.85 mm long, subequal, pale yellow. Styles 3. Capsules 3.1–3.8 mm long, narrowly ovoid. Seeds ca. 1.3 mm long, orbicular-reniform, compressed, the surface rugose. Chromosome number unknown.
Etymology.
Specific epithet refers to the geographic region of the Napali Coast valleys where this species occurs.
Specimens examined.
Hawaiian Islands. Kaua‘i: Waimea District: Olokele Valley, Lydgate 12 (BM-BM 013854574); Kopiwai, Ku‘ia Valley, [22°08'9.6"N, 159°41'32.7"W], Hobdy 200 (BISH, US); Ku‘ia Natural Area Reserve, in Mahanaloa Valley, N facing slope of valley N of Milolii Ridge, above confluence with Pa‘aiki Valley, [22°08'1.4"N, 159°41'48.5"W], Lorence & Wood 7620 (BISH [2], MO, PTBG); Mahanaloa Valley, above confluence of Kuia & Mahanaloa stream, 756 m, Wood 7430 (PTBG, US); Mahanaloa Valley, below confluence of Kuia & Mahanaloa stream, 700 m, Tangalin & Demotta 1981 (PTBG); Mahanaloa Valley, East from Weller # 2, 701 m, Tangalin & Aguraiuja 1953 (PTBG); Ku‘ia Valley, a tributary of Mahanaloa Valley, 200 ft inside Ku‘ia, right side slope, [22°8'17.2"N, 159°42'3"W], Perlman 472 (BISH, US); Makaha Valley, 823 m, Wood et al. 15662 (PTBG), 790 m, Wood & Perlman 17429 (PTBG); Makaha valley, near bottom of gulch, North facing slope, 772 m, Perlman et al. 25234 (PTBG, US); Nuololo, north facing slopes above drainage, 954 m, Wood & Query 14517 (PTBG), Wood et al. 15266 (BISH, PTBG, US), Wood et al. 15568 (BISH, PTBG, US), Wood et al. 15670.01 (PTBG). Hanalei District, Kalalau Valley, in back of valley, native cliffs and ridges, along ridge, [22°09'7.2"N, 159°37'42.8"W], Wood et. al. 1973 (PTBG, US).
Cultivated specimens.
Kaua‘i. Mahanaloa Valley, up valley from old horse trail, S side of valley, Perlman & Obata 12074 [cult. Wagner & Shannon 6805] (BISH, PTBG, US), Perlman & Obata 12074 [cult. 1991, Weller & Sakai s. n.] (US).
Distribution.
(Fig. 3). Schiedea napaliensis occurs in Waimea and Hanalei districts in the Napali Coast valleys of Makaha, Nualolo, Mahanaloa, Ku’ia, Pa’aiki, and Kalalau, and formerly in the Olokele Valley in the Waimea District, in open areas of diverse mesic forest; 750– 950 m.
Conservation status
Only a single naturally established plant of S. napaliensis occurs in the wild at present. The causes for the decline of this species include browsing by introduced ungulates, erosion resulting from ungulate activity, and consumption of seedlings by introduced mollusks. Using seed collections or plants propagated in tissue culture at the Lyon Arboretum, plants representing three localities (Nualolo, Mahanaloa, and Makaha) were used in a greenhouse crossing program to produce outcrossed seeds for restoration efforts. Numerous plants have been introduced into protected areas on Kaua‘i by the Plant Extinction Prevention Program, Division of Forestry and Wildlife, State of Hawai‘i, and appear to be growing well. Whether these plants will produce seeds capable of establishing new generations of plants remains to be seen.
description: Published as part of Wagner, Warren L. & Weller, Stephen G., 2025, A realigned taxonomy for the Schiedea kauaiensis – S. perlmanii species pair (Caryophyllaceae) based on recent collections and new analyses that require nomenclatural changes for both species, pp. 113-123 in PhytoKeys 254 on pages 113-123, DOI: 10.3897/phytokeys.254.148438