吕宋薯蓣 lu song shu yu

Dioscorea cumingii var. inaequifolia (Elmer ex Prain & Burkill) Burkill; D. cumingii var. polyphylla (R. Knuth) Burkill; D. heptaphylla Sasaki; D. inaequifolia Elmer ex Prain & Burkill; D. polyphylla R. Knuth.

Rootstock unknown. Stem twining to left, minutely yellow puberulent, prickly. Leaves alternate, palmately (3 or)5- or 7(or 9)-foliolate; petiole 7--9 cm; middle leaflet lanceolate, 8--12.5(--18) × 3--4.2 cm, ± herbaceous, puberulent, glabrescent except along veins, pinnately veined, base attenuate into indistinct petiolule, margin entire, apex caudate-acuminate; lateral leaflets obliquely elliptic, 6.5--9 × 2.3--3.2 cm, usually ± 2-veined from near base. Male spikes to 1.5 cm, in axillary panicles to 50 cm with 2 levels of branching, most parts densely gray tomentose. Male flowers: solitary; pedicel to 0.6 mm; bract and bracteoles forming involucel around perianth, bract cordate, ca. 1.5 mm, longer than perianth, bracteoles ovate, equaling perianth, tomentose, apex caudate; perianth drying dark, glabrescent, outer lobes oblong-ovate, to 2 mm, inner ones slightly smaller than outer; stamens 3; staminodes longer than stamens. Female spike solitary, 16--30 cm. Capsule oblong, 4--5 cm, puberulent when young, glabrescent, base cuneate, apex rounded; wings 0.9--1.3 cm wide. Seeds inserted near apex of capsule; wing pointing toward capsule base, ca. 0.9 × 0.5 cm. Fl. Apr, fr. Aug--Feb.

Taiwan (Lan Yu opposite SE coast), ?Yunnan [Indonesia, Philippines].

No material from Yunnan has been seen by the present authors, and the record from there requires confirmation, especially because there are no other records from the Asian mainland.