1. Drynaria rigidula (Swartz) Beddome, Ferns Brit. India. t. 314. 1869.
硬叶槲蕨 ying ye hu jue
Polypodium rigidulum Swartz in Schrader, J. Bot. 1800(2): 26. 1801; Drynaria baudouinii E. Fournier; D. diversifolia (R. Brown) J. Smith; D. gaudichaudii (Bory) Gaudichaud; D. pinnata Fée; D. rigidula var. koordersii Alderwerelt; Goniophlebium rigidulum (Swartz) T. Moore; Phymatodes gaudichaudii (Bory) C. Presl; Polypodium baudouinii (E. Fournier) Baker; P. diversifolium R. Brown (Mar 1810), not Willdenow (Jun 1810); P. gaudichaudii Bory; P. rigidulum var. vidgeni F. M. Bailey; P. speciosum Blume.
Rhizome shortly creeping, 1-2 cm in diam.; scales brown to dark brown, with a lighter margin, spreading, peltate, 5-13 × 0.5-1.5 mm, margin ciliate, apex acute to acuminate; fronds dimorphic, rachises persistent; basal fronds 10-30 × 5-15 cm, lobed from 1/3-4/5, margin irregularly and finely denticulate; foliage fronds stalked, stipe up to 40 cm, not winged, with 2 rows of nectaries; lamina pinnate, 25-100(-200) × 12-50 cm, apex aborted; pinnae articulate to rachis, all equally long or smaller toward apex, 8-25(-30) × 0.5-1.5 cm, base narrowly cuneate, margin crenate to serrate, apex obtuse to acuminate, free veinlets simple or absent, hydathodes absent. Sori in 1 row between costa and margin, costal, single between veins, orbicular, sunken. Spores with short, blunt spines and globules.
Epiphytic, encircling tree trunks many times, rarely epilithic; sea level to 2000(-2400) m. Hainan, SW Yunnan [Malaysia, Myanmar, Thailand, Vietnam; tropical Australia, Pacific islands (Polynesia)].
Drynaria rigidula differs from all other species of Drynaria by the pinnate fronds. It is the sole member of D. sect. Poronema J. Smith, to appropriately show its isolated position.