Scaphochlamys petiolata (K. Schum.) Smith (1987: 210)

Hin, Ooi Im, Kalu, Meekiong & Yeng, Wong Sin, 2017, A review of Scaphochlamys (Zingiberaceae) from Borneo, with description of eleven new species, Phytotaxa 317 (4), pp. 231-279 : 267-269

19. Scaphochlamys petiolata (K. Schum.) Smith (1987: 210) .≡ Haplochorema petiolatum Schumann in Engler (1904: 90). ≡ Borneocola petiolatus (K. Schum.) Sam in Sam et al. (2016: 47). Type:—MALAYSIAN BORNEO. Sarawak: 1st Division, Gunung Singai (“Mt. Singhi”), 11 December 1892, G.D. Haviland 2026 (lecto K!, isolecto SAR, designated by Searle, 2010: 110), Figure 19

Terrestrial, perennial, clumping herbs, to c. 45 cm tall. Rhizome slightly below the ground, c. 5 mm in diameter, externally greenish brown to light brown, internally light brown. Elements 0.5–3 cm apart, 1-foliate; leafless sheath c. 4, 1.5–7 cm long, brownish green to brown, glabrous, drying with age; leaf sheath c. 1.8 cm long, membranous, brownish green, glabrous, drying with age; ligule obscure; petiole 15–30 cm long, canaliculate, green with scattered tiny white dots, pulvinate at base; lamina 8–12.5 × 4–5 cm, usually asymmetric, ovate to lanceolate, chartaceous, margin plicate, base sub-truncate to slightly rounded, apex acute to acuminate; adaxial surface medium green to dark green, glabrous, midrib sunken, lateral veins conspicuous; abaxial surface light green, pubescent, midrib raised, main lateral veins slightly visible. Inflorescence 6.5–8 cm long, emerging from near leaf base inside sheaths, tightly congested, comprised of 3–5, 2-flowered cincinni borne on a peduncle, flowering spirally from base to apex; peduncle 4–5 cm long, light green with dense tiny white dots, glabrous, covered by sheaths; bract c. 3–5, c. 25 × 5 mm, spirally arranged, lanceolate, apex acute, brown to brownish white, membranous, each subtending c. 2 flowers; bracteole c. 2, 5–17 mm long, brownish white, shorter than bracts but barely distinguishable from bract; flower 3.5–4.5 cm long; calyx 9–11 mm long, brownish white, slightly pubescent near base, apex acute; floral tube 3–3.5 cm long, brownish white, sparsely pubescent; corolla lobes c. 10 mm long, lanceolate, creamy white, glabrous, apex acute, hooded; staminodes 5–7 mm long, linear to slightly lanceolate, adaxial surface covered with glandular hairs, creamy white, apex acute to obtuse; labellum 12–13 × 10–11 mm, spathulate, adaxial surface covered with glandular hairs, white at base and violet to apex with a light yellow median band, apex 2-lobed, indented c. 3 mm, lobes sometimes slightly overlapping; stamen c. 5 × 1.5 mm, covered with glandular hairs, white; filament c. 1 mm long; anther thecae 2, c. 3.5 mm long, spurred c. 0.5 mm basal at one side, crest c. 0.5 mm long, trilobed; stigma less than 1 mm long, club-shaped with 2 dorsal knobs, ostiole ciliate, forward facing; style c. 3.5 cm long, white, sparsely pubescent; ovary c. 2 mm long, 1-locular,white, densely pubescent; epigynous glands 2, c. 2 mm long, free, needle-like, brownish white. Fruit c. 11 × 4 mm, dehiscent capsule, ovoid, brownish green (brown translucent cuticle-like pericarp enclosing green seed), sparsely pubescent, subtended by marcescent bracts. Seeds c. 9 × 3 mm, ovoid, glabrous, green; aril c. 4 mm, lacerate, brownish white; perisperm white.

Distribution and ecology: — Endemic to Mount Singai, Bau, Kuching Division, Sarawak on kerangas (tropical heath) forest, flat area near stream, of c. 460 m elevation.

Additional specimens examined:— MALAYSIAN BORNEO. Sarawak: Kuching Division , Bau, Gunung Singai, 01°30’14.6”N, 110°09’57.9”E, 17 November 2013, I.H. Ooi & T. Jepom, OIH71, OIH 72 & OIH73 (SAR) ; Gunung Singai , 01°30’14.6”N, 110°09’57.9”E, 21 December 2013, I.H. Ooi OIH78 (SAR) ; Gunung Singai , 01°30’14.6”N, 110°09’57.9”E, 19 July 2014, I.H. Ooi OIH253 (SAR) .

Conservation status:—Near Threatened (NT). This species is restricted to the type locality on one side of Gunung Singgai. Gunung Singgai serves as a religious retreat to local community and thus is relatively undisturbed.

Discussion:—The name Scaphochlamys petiolata has been widely applied to almost all Bornean Scaphochlamys specimens with a long slender petiole. However, recollection of S. petiolata from its type locality enabled conclusion that the species is restricted to Gunung Singai, and led to recognition of several distinctive taxa ( S. biru , S. multifolia and S. hasta ). Scaphochlamys petiolata is the only species among these taxa that is monophyllous as an adult plant. Scaphochlamys biru differs from S. petiolata by the inconspicuous lateral veins on the leaf lamina while the inflorescence of S. multifolia is terminal within sheaths; S. hasta is readily distinguishable by its long lanceolate lamina with long slender petiole.

Figures

FIGURE 19. Scaphochlamys petiolata. A. plant in habitat. B. flower bud. C. inflorescence. D. flowers. E. germinating seed. A–E from OIH71.