思茅叉蕨 si mao cha jue

Tectaria polymorpha (Wallich ex Hooker) Copeland var. subcuneata Ching & Chu H. Wang; T. simaoensis Ching & Chu H. Wang.

Plants terrestrial, 0.8-1 m tall. Rhizome creeping, long, 0.8-1 cm in diam., scaly at apex and stipe bases; scales dark brown and light glossy, pale along margins, lanceolate, 2-3 mm, thickly membranous, subentire, apices acuminate, caducous downward. Fronds widely spaced; stipe stramineous, 30-60 cm, 4-5 mm in diam., clothed with light brown articulate hairs above, glabrescent beneath. Lamina odd-pinnate, dark green when dried, ovate to oblong, 30-45 × 25-30 cm, papery, both surfaces glabrous, margin cartilaginous; rachises, costae, and lateral veins stramineous, pubescent adaxially, glabrescent abaxially, grooved adaxially and raised abaxially; terminal pinna ovate to oblong, entire, ca. 20 × 7-9 cm, stalk 2-3 cm, base broadly cuneate, apex caudate; lateral pinnae 2-4 pairs, simple, ovate-lanceolate, 18-20 × 5-6 cm, slightly oblique, opposite, subentire, interval 2-5 cm, bases slightly asymmetrically cuneate, apices abruptly caudate; basal pinnae shortly stalked, pinnae sessile toward apices. Veinlets forming conspicuous subhexagonal areoles, raised on both sides, included veinlets simple or forked. Sori orbicular, on anastomosing veins, in irregular 4-6 rows between lateral veins; indusia brown, orbicular, membranous, glabrous, entire, caducous.

Dense forests; 600-1100 m. Yunnan [India, Malaysia, Myanmar, Thailand, Vietnam].

Tectaria herpetocaulos is very similar to T. polymorpha but can be easily recognized by its creeping rhizomes and abaxially glabrous laminae; its pinnae are simple and broadly rounded at the base and somewhat reminiscent of a Cyclosorus (Thelypteridaceae).