三指假瘤蕨 san zhi jia liu jue

Polypodium trilobum Houttuyn, Nat. Hist. 14: 148. 1783; Crypsinus trilobus (Houttuyn) Copeland; Phymatodes triloba (Houttuyn) Ching; P. triphylla (Jacquin) C. Christensen & Tardieu; Phymatopsis triloba (Houttuyn) Ching; Phymatopteris triloba (Houttuyn) Pichi Sermolli; Pleopeltis incurvata (Blume) T. Moore; Polypodium incurvatum Blume; P. triphyllum Jacquin.

Rhizome 3-4 mm in diam., densely scaly throughout; scales castaneous at center, paler brown toward margin, ovate-lanceolate, rounded at peltate base, margin entire, apex acuminate. Fronds dimorphic, rarely intermediate with upper part fertile, lower part sterile. Sterile fronds: stipe light brown, 10-20 cm, glabrous; lamina trilobate or pinnatifid, subdeltoid, rarely simple, 10-20 × 10-15 cm, margin entire; lateral lobes 1-3 pairs, ascending, broadly lanceolate, apical lobe broader, up to 4-5 cm wide; 12-15 × 2-3 cm, apex acute or obtuse; costa raised, lateral veins distinct, veinlets hardly visible. Lamina leathery, both surfaces glabrous. Fertile fronds: stipe 20-30 cm; lamina trilobate or pinnatisect with 2-4 pairs of lateral lobes; rachis narrowly winged or wingless in lower parts; lobes contracted, linear, less than 1 cm wide, apex acuminate. Sori sunken in deep cavities on abaxial side, raised on adaxial surface.

Epiphytic on tree trunks or on rocks; below 1300 m. Hainan [Indonesia, Malaysia, Philippines, Thailand, Vietnam].