Family

Hymenophyllaceae

Nomenclature

Hymenophyllum holochilum (Bosch) C.Chr., Index Filic.: 362. 1905; Copel., Philipp. J. Sci. 64: 34, pl. 14. 1937; Holttum, Rev. Fl. Malaya ed. 1, 2: 77, f. 17. 1955 [‘1954’]; Tagawa & K.Iwats., Fl. Thailand 3: 612. 1989; Boonkerd & Pollawatn, Pterid. Thailand: 74. 2000. – Didymoglossum holochilum Bosch, Pl. Jungh. 1: 561. 1856. – Meringium holochilum (Bosch) Copel., Philipp. J. Sci. 67: 41. 1938; Ching, Fl. Reipubl. Popularis Sin. 2: 149. 1959; Tagawa & K.Iwats., Fl. Thailand 3: 77, f. 5.4. 1979.

Description

Rhizome slender, bearing rather sparse pale brown hairs. Stipes hairy, wingless or very narrowly winged on upper portion with a row of cells on each side, 1–2 cm long. Laminae oblong, round to moderately acute at apex, 3–6.2 cm long, 1–2.6 cm wide, bipinnatifid to tripinnatifid; rachis slender, hairy beneath, narrowly winged throughout with usually flat and not toothed wings, or sometimes not winged in lower portion; pinnae 5–9 in alternate pairs, oblong to ovate, with 2–7 segments; segments usually simple, rarely forked or trilobed; ultimate segments oblong, round at apex, distinctly toothed but not crisped, to 1.5 mm broad. Sori solitary, on basal acroscopic lobes of pinnae; involucre with tuberous base and bivalvate upper portion, cleft to half-way, about 2 mm long, 1 mm broad; lips subdeltoid, moderately acute at apex, subentire or slightly wavy or toothed .

Distribution in Thailand

PENINSULAR: Ranong, Nakhon Si Thammarat.

Wider Distribution

Malesia.

Ecology

On trees in tropical evergreen forest at about 900 m alt.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 4396, Nakhon Si Thammarat, Namtok Yong National Park (E).