Endemic to N & NE Borneo from NE Sarawak (notably Mulu N.P.) throughout Brunei to NE Sabah; frequently locally abundant (as, e.g., at Kuala Belalong, Temburong, Brunei).
Rheophytic on and among shale boulders in stream beds, or on stream banks; altitude: up to ca. 200 m asl.
Rheophytic herb to 13-20 (-25) cm tall. Stem short, erect, 3-4 cm long, c. 1 cm diam. Leaves several; petiole minutely tuberculate when dry, relatively short, 2.5-5 cm long, c. 2 mm diam., tinged brown, canaliculate adaxially and with fine strongly to weakly crispate wings, sheathing at the extreme base with the wings extended into a narrow ligular portion 2-4 cm long; blade coriaceous, dark green adaxially, paler abaxially, very narrowly elliptic to oblanceolate, 6-16 cm long × 1.2-3 cm wide, the base cuneate, the apex acute and apiculate for 2-3 mm; midrib very prominent abaxially, somewhat raised adaxially, with 7-9 fine, adaxially obscure primary lateral veins on each side diverging at c. 30° and running to a well-defined submarginal vein; secondary venation very fine and dense; tertiary venation obscure. Inflorescence solitary (occasionally two together, but interspersed with foliage leaves); peduncle much exceeding the petioles, 12-15 cm long, erect. Spathe held obliquely erect, c. 3 cm long, ovoid, apically beaked for c. 3 mm, creamy white to salmon pink (sometimes pink and whitish), the upper part caducous. Spadix free, sessile to very shortly stipitate, 1.5-2 cm long, subcylindric (becoming distinctly narrower at the sterile zone at anthesis - see Notes); female zone 5-6 mm long × 4-5 mm diam.; staminodes absent from among the pistils and usually also the base of the female zone - occasionally one or two present and then subsessile, subglobose, c. 0.5 mm diam., drying white; ovary shortly columnar, c. 1 mm high; stigma sessile, broadly discoid, slightly centrally impressed, contiguous with neighbouring stigmas, c. 0.7 mm diam., coarsely papillate at anthesis; sterile interstice c. 4 mm long and in diam., composed of c. 5 irregular whorls of columnar, irregularly polygonal staminodes with slightly raised rims, c. 0.5 mm diam.; male zone 0.8-1 cm long, basally isodiametric with sterile interstice, slightly tapering to an obtuse tip, fertile to apex or with a few terminal abortive stamens; stamens more or less irregularly rectangular-dumbbell-shaped, flat-topped apart from a shallow groove across the connective running from pore to pore, c. 0.5 mm across; thecae opening through single apical pores with the pollen extruded in threads. Fruiting spathe green to brownish, broadly obconic, c. 1.5-1.8 cm diam.; berries clustered, cylindric, topped with old stigma remnants, 1.9-2 mm long, c. 1 mm diam.; seed subcylindric, brown, c. 1.6 mm long, 0.3 mm diam., with long curved micropylar appendage 0.8-1 mm long.
Malesia: endemic to NW Borneo.
Rheophytic among boulders in stream beds or on stream banks, below 100m alt.