Bucephalandra elliptica
Small solitary obligate rheophytic herbs to 20 cm tall. Stem creeping and rooting with active portion sub-erect, c. 1.3 cm in diam. Leaves c. 6 to gether; petiole 5 - 6 cm long × c. 2 mm in diam., adaxially canaliculate, medium green, sheathing at extreme base, wings extended into a very narrowly triangular ligular portion to 3 cm long; blade lanceolate, rather oblique, 9 - 13 cm long × 3 - 4 cm wide, somewhat coriaceous, semi-glossy medium green adaxially, paler green abaxially with darker green veins, base rounded, apex acuminate, apiculate for c. 2.5 mm, margin undulate, quite strongly so in larger individuals; midrib abaxially and adaxially prominent; primary lateral and interprimary veins not differentiated, together amounting to c. 8 per side, diverging at c. 30° and running to a marginal vein; secondary venation adaxially ± obscure, abaxially fine; tertiary venation adaxially obscure, abaxially forming a faint tessellate reticulum. Inflorescence solitary; pe duncle fairly stout, exceeding petioles, 6 - 10 cm long × c. 2 mm in diam., terete, dull medium green. Spathe oblong-ovate, not constricted, c. 6 cm long; lower spathe narrowly funnel-form, bright green, shading to yellow, persistent; limb inflating, producing a slit near tip, then crumbing-caducous, glossy white, rostrate for c. 1.5 cm, and apiculate for c. 2 mm, apiculum green. Spadix 2 - 3 cm long; pistillate zone c. 7 - 9 mm long × 3 - 4 mm wide, with c. 3 spirals of pistils; pistils dense, rhomboidal-cylindric, c. 0.5 mm in diam., limegreen; stigma sessile, umbonate, c. ½ diameter of ovary, impressed with edges of pistil forming a raised rim, papillate and with a conspicuous stigmatic droplet at anthesis; pistillodes lorate-clavate, c. 1.5 mm long, glossy white; interstice with 2 rows of scale-like staminodes, these c. 2 mm long × c. 2 mm wide, ventrally with median-line swollen and distally somewhat spathulate, pale creamy white with claw green; staminate zone 1 - 1.5 cm long × 1 - 1.5 cm in diam., consisting of 5 - 7 rows of flowers; staminate flowers upward-directed during pistillate anthesis, reflexing to almost perpendicular with spadix axis during staminate anthesis, creamy white; stamen large, c. 2 mm across × c. 1.5 mm tall; filament short; connective triangular-prismatic; thecae inserted ventrally, gibbose-ellipsoid, c. 1 mm long × c. 0.5 mm wide, smooth; thecae horns c. ¼ length of associated theca, setaceous, upward-curved; appendix bluntly cylindrical to fusiform, 2 - 3 cm × 1 - 1.7 cm in diam., cream; appendix staminodes irregularly rhombic-cylindric, lowermost in groups of 3, truncate, 0.5 - 1 mm in diam., top surface papillate. Fruiting spathe widely and shallowly funnel-form, c. 1 cm in diam. × c. 1.5 cm tall; fruits and seeds not seen.
SW Sarawak. Known with certainty only from Sri Aman. See Remarks for other potential locations.
Bucephalandra elliptica occurs on sandstone riversides and stream boulders under open lowland perhumid forest at c. 150 m above sea level.