云南海金沙 yun nan hai jin sha

Lygodium giganteum Tagawa & K. Iwatsuki.

Rhizome very shortly creeping, bearing fronds close together, apices and bases of stipes densely covered with dark brown hairs. Fronds very large, climbing to more than 2 m; stipes at most 20 cm, stramineous to dark, densely pubescent throughout, very narrowly winged; rachis like upper part of stipes, 2-4 mm in diam., densely pubescent; primary rachis branches 8-15 mm, apex dormant, covered with dense brown hairs; secondary rachis branches pinnate to bipinnate, up to 25 cm long and wide; in larger ones tertiary rachis branches with few pinnae, forming a pentagonal outline, tertiary pinnae palmately 5-lobed to hastate, with large central lobes, deeply cordate at base, rounded or very moderately acute at apex; axes of branches of secondary and of higher orders stramineous, densely pubescent with pale unicellular hairs, with distinct articulation at every junction; ultimate lobes larger, oblong-subdeltoid to oblong, up to 20 × 4 cm, herbaceous to soft papery, irregularly and slightly dentate at margin, rounded at apex; stalks very narrowly winged, articulate at base of lamina, up to 15 mm; veins forked 3-4 times, all free; both surfaces of lamina as well as veins hairy. Sporangia-bearing lobes protruding at margin of ultimate lobes, 2-8 × ca. 1.2 mm; indusia hairy.

Among shrubs, dry slopes in thickets, usually in deciduous forests at low to middle elevations; 300-1300 m. Guangxi, Guizhou, Yunnan [Myanmar, Thailand].

In hairiness and articulation at base of ultimate segments (without an actual function as an abscission zone), Lygodium yunnanense is similar to L. salicifolium and rather difficult to distinguish from the latter in the Myanmar-Yunnan region. The pattern of division of the fronds is like that of L. flexuosum, but L. yunnanense is a much larger species.