Nephelaphyllum maliauensis Suetsugu, M.Suleiman & Tsukaya, 2018

Suetsugu, Kenji, Suleiman, Monica & Tsukaya, Hirokazu, 2018, Nephelaphyllum maliauensis (Orchidaceae; Collabiinae), a new species from the Maliau Basin, Sabah, Borneo, with a discussion of the taxonomic identities of N. pulchrum, N. latilabre and N. flabellatum, Phytotaxa 336 (1), pp. 89-94 : 89-90

Nephelaphyllum maliauensis Suetsugu, M.Suleiman & Tsukaya , sp. nov. ( Figs. 1 , 2 )

Type:— MALAYSIA. Sabah: Maliau Basin Conservation Area, along the Seraya Trail , from N4.7422, E116.9638 to N4.7428, E116.9638, 28 September 2016, Tsukaya, Suetsugu & Suleiman, TSS-24 (holotype: BORH; isotype, flower in spirit at KYO) .

Nephelaphyllum maliauensis is similar to N. pulchrum but is distinguished by its spatulate, narrower lip.

Terrestrial herbs, ca. 6.0 cm tall with creeping rhizomes that produce roots at nodes. Roots yellowish brown, with minute root hairs. Pseudobulb cylindric, 0.7–1.1 cm long, petiole-like. Stem erect, terete, 5.0 cm long, greyish to purplish green, glabrous. Leaves 3–4, widely spaced along stem or clustered apically; lamina cordate, 2.9–4.4 × 2.0– 2.8 cm, acute at apex, pale olive to grey-green, reticulately veined darker green, with dark blotches above, purple below. Inflorescences terminal, 3–4 flowered; rachis 1.0 cm long; floral bracts 0.7 × 0.4 mm, ovate, acute, papery, with pale brown speckles and dark purple flecks. Flowers non-resupinate, erect; sepals and petals linear, acute, reflexed over the ovary, pale pink with purple veining; dorsal sepal 9.3 × 2.1 mm; lateral sepal 11.0 × 1.9 mm; lateral petal 10.4 × 1.9 mm. Lip, spatulate, 16.0 mm × 4.5 mm in nature, but ca. 8.4 mm wide when dried and flattened, entire, obtuse, pale yellow, with three orange, longitudinal, finely haired ribs in the middle of the apex, sides embracing the column; spur cylindrical, shallowly bilobed, 3.6 mm long, 2.1 mm in diameter. Ovary pedicellate, 8.7 mm long, narrowly clavate, 6-angled, pale green to reddish purple. Column 7.7 mm long, 2.4 mm in diameter, oblong, broadly winged; anther cap 1.8 × 1.8 mm, with 2 conical dorsal projections. Pollinia 8.

Distribution, phenology, and conservation status: — Nephelaphyllum maliauensis is currently only known to occur as a single population of less than 10 flowering individuals in kerangas forest, which is dominated by dipterocarps and Agathis species.

Notes: — Nephelaphyllum maliauensis is similar to N. pulchrum (Blume 1825, 1858) but is clearly distinguished by its lip shape (spathulate, 16.0 × 8.4 mm vs. oblong, 13.0–20.0 × 11.0–12.0 mm (Seidenfaden & Wood 1992, Comber 2001; Table 1).

Figures

FIGURE 1. Nephelaphyllum maliauensis in the Maliau Basin, Sabah, Borneo(type locality).A.Flowering plant.B. Flowers.Photographed by Kenji Suetsugu.

FIGURE 2. Nephelaphyllum maliauensis.A. Habit. B–D. Flower and pedicellate ovary. E. Flattened lip. F. Dorsal sepal. G. Lateral petal. H. Lateral sepal. I. Anther cap and pollinia. J. Column. K. Bract. (A. Scale bar = 1 cm; B–H, J–K. = 3 mm; I = 1 mm.) Drawings by Kumi Hamasaki.