Family

Hymenophyllaceae

Nomenclature

Hymenophyllum serrulatum (C.Presl) C.Chr., Ind Fil.: 367. 1905; Holttum, Rev. Fl. Malaya ed. 1, 2: 78, f. 19. 1955 [‘1954’]; Tagawa & K.Iwats., Fl. Thailand 3: 611. 1989; Boonkerd & Pollawatn, Pterid. Thailand: 75. 2000. – Didymoglossum serrulatum C.Presl, Hymenophyllaceae: 115, 140. 1843.

Meringium meyenianum C.Presl, Hymenophyllaceae: 116, pl. 8B. 1843; Tagawa & K.Iwats., Acta Phytotax. Geobot. 23: 51. 1968; Tagawa & K.Iwats., Fl. Thailand 3: 76. 1979. – Hymenophyllum meyenianum (C.Presl) Copel., Philipp. J. Sci. 64: 25, pl. 8. 1937.

Hymenophyllum smithii Hook., Sp. Fil. 1: 97, t. 35B. 1844; Bedd., Handb. Ferns Brit. India: 34. 1883.

Description

Rhizome slender, covered with stiff brownish hairs. Stipes terete, without wings, with caducous hairs, 1.5–3 cm long; fronds very variable, tripinnatifid, oblong-lanceolate to oblong-ovate, acute at apex, gradually narrowing towards base, 4–10 cm long, 1.5–3.5 cm wide; rachis winged except in the basal part, hairy; pinnae sessile, round to acute at apex, unequally cuneate at base; ultimate segments of each pinnule few, linear, round to moderately acute at apex, irregularly toothed and flat at margin; pale green in colour, the axes dark. Sori at the apices of short basal acroscopic segments in the upper part of fronds; involucre tubular with bilabiate mouth, the lips acute, entire .

Distribution in Thailand

PENINSULAR: Ranong, Yala.

Wider Distribution

Throughout Malesia.

Ecology

On mossy tree trunks or on moist rocks in deep shade in evergreen forests; rather rare.

Proposed IUCN Conservation Assessment

Least Concern (LC). This species is widespread and not under any immediate known threat.