Bucephalandra sordidula S. Y. Wong & P. C. Boyce

Diminutive obligate rheophytic herbs c. 2.5 cm tall, occurring in extensive patches. Stem creeping with active portion sub erect, branching repeatedly, stems c. 1 - 2.5 mm in diam. Leaves appressed to ground, scattered along stems; petiole 0.5 - 1 cm long × c. 2 mm in diam., adaxially canaliculate, greenish brown, sheathing at extreme base, wings extended into a very narrowly triangular ligular portion to 1 cm long; blade obovate, 3 - 5 cm long × 1 - 1.5 cm wide, thinly coriaceous, olive-green adaxially, paler and reddish abaxially, base cuneate to sub-decurrent, apex rounded and apiculate for c. 1 mm, margin undulate to crispulate; midrib adaxially somewhat prominent, abaxially much finer, although reddish and therefore conspicuous; primary lateral and interprimary veins very fine and not differentiated, c. 8 veins per side; secondary venation abaxially forming a fine reticulum. Inflorescence solitary; peduncle greatly exceeding petioles, 5.5 - 7 cm long, conspicuously longitudinally sulcate, dark reddish brown with deeper brown speckles. Spathe broadly ovate, not constricted, c. 1.5 cm long; lower spathe funnel-form, dirty white with reddish brown speckles, especially in lower 1/2, later turning green with brownish speckles, persistent; limb gaping to form a distal slit at pistillate anthesis, reflexing at staminate anthesis, then caducous, externally dirty white with variable amounts of brownish red speckles, interior dirty white, apiculate for c. 1 mm, apiculum reddish brown. Spadix 6 - 7.5  mm long; pistillate zone c.  2  mm long × c. 1.5 mm in diam., with c. 2 spirals of pistils; pistils rhombic-globose, c. 0.3 mm in diam., bright green; stigma sessile, umbonate, c. 1/2 diameter of ovary, papillate at anthesis; pistillodes absent; interstice with 2 incomplete rows of scale-like staminodes, these c. 0.5 mm long × c. 0.7 mm wide, weakly spathulate, glossy white, later (post-anthesis) becoming green and persisting to cover developing fruit; staminate zone c. 1.5 mm long × c. 2 mm in diam., consisting of 2 or 3 rows of flowers; staminate flowers somewhat pinkish; stamen c. 1 mm across; filament short, stout; connective strap-shaped, glossy white; thecae inserted ventrally, ellipsoid, c. 1 mm long × c. 0.3 mm wide, smooth, pinkish, speckled darker pink; thecae horns c. 1/3 length of associated theca, setaceous, upward-pointing; appendix globose, c. 3 mm long × c. 2 mm in diam., glossy waxy white; appendix staminodes obpyramidal, somewhat regularly polygonal (individual staminodes not easily distinguished), flat-topped, c. 1 mm in diam. Fruiting spathe widely funnel-form, c. 5 mm in diam., with shield-shaped staminodes persistent, turning green, spent distal part of spadix falling; fruits and seeds not seen.