Ophioglossum japonicum (Thunb.) Sw.

Climbing fern.

Rhizome creeping, branching, short; rhizome scales blackish brown, linear, c. 2 mm long. Fronds deciduous, monomorphic, spaced 3 cm apart. Stipe and rhachis twining, forming the climbing stem of an elongated frond, growing to 30 m, from which arise short spurs bearing an opposite pair of dissected pinnae. Stipe 3 m long, strawcoloured, narrowly winged. Lamina 2-pinnate, twining rhachis, palmate or pinnate pinnae, indeterminate growth, with short, curved hairs on both sufaces. Sterile pinnae triangular, 10-20 cm long, 2-pinnate to 4-pinnatifid on the basal pinnae; basal lobes irregular lobed or dissected, finely covered with short hairs along the secondary rhachises and pinnule midribs, with scattered hairs along the veins, margins finely toothed, sometimes biserrate. Fertile pinnae 2- to 4-pinnate, smaller and more finely dissected than the sterile ones, with longer apical and shorter basal segments. Rhachis wiry, costules winged. Sporangia in 6-9 pairs, arranged in 2 rows on fertile lobes 1-5 mm long, lining and protuding from the pinnule margins.

Naturalised

japonicum: of Japan, where this fern was first collected by Carl Thunberg.

Damp sites on the fringes of moist evergreen forest adjacent to warm Eastern Cape coastline.

Native of temperate and tropical Eastern Asia; naturalised in Australia, Taiwan, Philippines, USA, South Africa.

South Africa.

Climbing, terrestrial.