Homalomena caput-gorgonis
Medium solitary evergreen, strongly aromatic (lime zest) mesophytic herbs to 1 m tall. Stem epigeal, erect, leafy, later the older parts leafless and decumbent with the active tip ascending. Leaves about six per module, c.8–10 together; modules subtended by a conspicuously two-keeled prophyll up to 13 cm long; petioles up to 70 cm long, sheathing for one fifth to one-quarter of their length, ascending to somewhat spreading, flexing slightly upwards at the 2–3 cm long pulvinus occurring about two-thirds along the petiole length, with one-third of the petiole lying distal to the pulvinus, petiole above the petiolar sheath weakly D-shaped in cross-section, petiole matte green, slightly scabridulous; petiolar sheath conspicuous, wings persistent, ± open, c.1.5 cm wide, the tips tapering and somewhat abruptly decurrent, stained dark brownish; blade thinly leathery, cordiform, up to 30 cm long × 27 cm wide, posterior lobes parallel, rounded, c.7 cm long, sinus obtuse, apex acute, tubularmucronate for c.2 mm, adaxially semi-glossy olive-green, abaxially matte paler olive-green with conspicuous darker pellucid striate interprimary venation especially near the blade margin, these more conspicuous on younger leaves; midrib moderately conspicuous, impressed adaxially, rounded-raised abaxially; primary lateral veins c.10 per side, the lower three arising ± simultaneously and associated with the posterior lobes, impressed adaxially with the areas of the blade between slightly quilted, slightly raised abaxially; interprimary veins of two types, one type alternating with primaries and only slightly less conspicuous, the second type comprising conspicuous pellucid darker veins, these very numerous and sometimes branching just after they exit the midrib; secondary and tertiary venation ± invisible. Inflorescences up to 30 together, produced sequentially in a gorgonoid synflorescence, smelling powerfully of liquorice at pistillate anthesis; peduncle terete, slender, up to 17 cm × 2 mm, reddish greenish brown, spreading with the inflorescence nodding at anthesis, inflorescence with spathe opening ventrally relative to the peduncle; spathe spreading at pistillate anthesis, broadly ovate-ellipsoid, not constricted, c.5.5 × 3 × 1.5 cm deep at anthesis, tipped with a rostrum c.3 mm long, margins reflexing during anthesis, spathe medium green in bud, the exterior bright medium green, glossy, at anthesis exterior green and interior greenish white with scattered minute paler glands. Spadix about three-quarters the length of the spathe, c.4 cm long including the brief stipe; stipe obliquely inserted on the peduncle, c.3 mm long on its shortest side, c.2 mm diameter, glossy pale green; pistillate flower zone about one-third the length of the spadix, c.1.2 × 0.8 cm; pistils densely arranged, almost cylindrical, c.1 × 0.6 mm, pale green; style very short, slightly narrower than the ovary; stigma almost equalling the ovary in width, capitate, greyish white, papillate at pistillate anthesis; interpistillar staminodes narrowly clavate, slightly exceeding the height of the associated pistil, ivory-white; staminate flower zone contiguous with the pistillate flower zone, c.2.2 cm × c.7 mm, very slightly fusiform, blunt, ivory; staminate flowers three to four staminate, stamens each with two anthers; stamens elongate-globose, connective embedded and ± invisible; thecae opening by a conspicuous lateral slit. Infructescence pendent, spathe fully persistent and turning deep green, ellipsoid, c.5.6 × 2.2 cm; fruit and seeds not observed.
Homalomena caput-gorgonis in appearance most closely approaches H. selaburensis, differing by the gorgonoid synflorescences carrying up to 30 inflorescences, the narrowly (versus broadly) clavate interstice staminodes, the shorter spathe (5.5 versus c.6.5 cm long), the leaf blades adaxially semi-glossy (as opposed to highly polished), and abaxially matter olive-green (versus matte pale green). Additionally, H. caput-gorgonis is overall greater in stature, notably by the proportionately much longer petioles.
Homalomena caput-gorgonis is so far known only from one restricted area of the foothill eastern approaches to Gunung Pueh, northwest Sarawak. Investigation of the southern end of the Gunung Pueh-Berumput massif is required to establish whether the range of the H. caput-gorgonis is genuinely limited.
Homalomena caput-gorgonis occurs on soil on the tops and upper sides of large granite boulders under lowland humid forest between 80 and 100 m altitude.