Rhaphidophora stenophylla (Araceae)
Large, rather robust, semi-leptocaul, homeophyllous liane to unknown ultimate height; seedling stage very slender terrestrial to climbing, leaves arranged in two ranks; pre-adult plants clinging, slender, with very narrow leaves; adult shoot comprised of elongated, clinging, physiognomically unbranched, non-flowering stems and free lateral, leafy flowering stems; stems terete to strongly compressed, but not rectangular in cross-section, without cataphyll, prophyll and petiolar sheath fibre, internodes 1-3 x 0.2-2 cm, separated by prominent almost straight, slightly corky leaf scars; flagellate foraging stem absent; clasping roots arising from nodes and internodes; feeding roots not observed; LEAVES spiro-distichous in mature plants; cataphylls and prophylls caducous; petiole deeply canaliculate, 2-16 x 0.2-1 cm, apical geniculum small and very obscure, basal geniculum weakly defined; petiolar sheath very prominent, broadly winged and extending to apical geniculum, persistent almost through to leaf fall; lamina entire, linear-lanceolate to narrowly lanceolate or narrowly oblong-lanceolate, slightly falcate, 9-38 x 1.5-4 cm, subcoriaceous, base subacute to slightly decurrent, apex acute to briefly acuminate with a prominent tubule; midrib raised abaxially, sunken adaxially; primary venation pinnate, slightly raised abaxially, almost flush adaxially; interprimaries reticulate-parallel to primaries, almost indistinguishable from them, slightly raised abaxially, almost flush adaxially; secondary venation reticulate, hardly visible; INFLORESCENCE solitary, subtended by a ± fully developed foliage leaf; peduncle slightly laterally compressed to terete, 6-10 x c. 1 cm; spathe broadly canoe-shaped, stoutly long-beaked, 11-13 x 1.5-2.5 cm, stiffly fleshy, yellow, caducous leaving a large scar at the base of the spadix; spadix cylindrical, slightly curved, long stipitate, 6-9 x 1.5-2.2 cm, inserted level to almost truncate on stipe, white; stipe slender to stoutly terete, 2.5-3 x 3-0.4 cm; stylar region rhombohexagonal, 1-2 x 1-1.5 mm, conical; stigma punctiform, prominently raised, c. 0.3 mm diam.; anthers strongly exserted at male anthesis; INFRUCTESCENCE not observed.
Unmistakable by the long, narrow leaves, persistent winged petiolar sheath, long stipitate spadix and prominently raised stigma. There exist plants with broader laminas than typical (Brass 27691 & 28311 are of this broad-leaf type) that may be confused with Rhaphidophora discolor (also flowering on free shoots and with long-stipitate spadix), although the latter is readily distinguished by the broader leaf laminas, petiolar sheath degrading to strips and fibres, larger (13.5--19 x 2.2--4 cm) spadix and flat stigmas. Scindapsus schlechteri K. Krause is superficially similar in its narrow leaf lamina and persistent-winged petioles but differs, aside from a single ovule per ovary (and thus one-seeded fruits), by the sessile spadix and thicker leaf lamina with almost no visible venation.
Papua New Guinea (including the Louisiade Archipelago).
Monsoon lower montane forest to submontane primary forest on moderate to steep slopes, sometimes on limestone.