Family

Hymenophyllaceae

Nomenclature

Hymenophyllum acanthoides (Bosch) Rosenst., Bull. Jard. Bot. Buitenzorg, Ser. 2, 2: 25. 1911; Copel., Philipp. J. Sci. 64: 45, pl. 17. 1937; Holttum, Rev. Fl. Malaya ed. 1, 2: 20. 1955 [‘1954’]; Tagawa & K.Iwats., Fl. Thailand 3: 612. 1989; Boonkerd & Pollawatn, Pterid. Thailand: 72. 2000. –Didymoglossum acanthoides Bosch, Pl. Jungh. 1: 16. 1856. – Meringium acanthoides (Bosch) Copel., Philipp. J. Sci. 67: 42. 1938; Ching, Fl. Reipubl. Popularis Sin. 2: 151. 1959; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 37. 1967; Tagawa & K.Iwats., Acta Phytotax. Geobot. 23: 51. 1968; Tagawa & K.Iwats., Fl. Thailand 3: 78, f. 5.5. 1979.

Description

Rhizome slender, covered with brownish hairs when young. Stipes 1–3 cm apart, winged, 0.7–1.5 cm long. Laminae variable in size and form, bipinnate to tripinnatifid, oblong-subdeltoid, moderately acute at apex, broadly cuneate to subcordate at base, 1–2 cm long and wide (at most 3.5 cm long in the largest ones); rachis winged; pinnae with several segments, ovate to oblong, round at apex, unequally cuneate at base; ultimate segments round or obtuse at apex, 1 mm or so wide, the margin sharply toothed and conspicuously crisped, the fronds never extending in a plane. Sori at apices of short acroscopic segments, usually in apical part of fronds; involucre tubular with bilabiate mouth, winged, also with a few accessory wings, the lips round and sharply toothed .

Distribution in Thailand

PENINSULAR: Nakhon Si Thammarat, Phatthalung, Trang, Yala.

Wider Distribution

Tropics of Asia, Java, to New Guinea, north to Taiwan.

Ecology

On mossy tree trunks or on moist mossy rocks in tropical evergreen forest at low to medium altitudes.

Similar species

Hymenophyllum denticulatum Sw.

Proposed IUCN Conservation Assessment

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