Family

Hymenophyllaceae

Nomenclature

Crepidomanes megistostomum (Copel.) Copel., Philipp. J. Sci. 67: 60. 1938; Tagawa & K.Iwats., Fl. Thailand 3: 88. 1979; Tagawa & K.Iwats., Fl. Thailand 3: 613. 1989; Boonkerd & Pollawatn, Pterid. Thailand: 71. 2000. – Trichomanes megistostomum Copel., Philipp. J. Sci. 51: 191, pl. 23, f. 4–6. 1933. – Type: Md. Haniff & Md. Nur 3981, Thailand (SING).

Description

Rhizome long creeping, filiform with numerous rhizoids. Stipes short, winged in upper part. Laminae almost digitate in appearance, bluntly quadrangular in outline, round at apex, cuneate at base, about 2 cm long including stipes of 5–8 mm in length, 1 cm wide, bipinnatifid or subdigitate, pinnae with 2–4 segments; segments round at apex, entire at margin, about 1 mm in breadth, the base decurrent to rachis, continuing to the wings on the upper part of stipes; false veinlets short, oblique or somewhat elongate between costa and margin of segments, submarginal ones wanting. Sori solitary, terminal on the ultimate segments, extruded on narrow constriction, cup-shaped, about 1.5 mm long; the mouth of involucre bilabiate .

Distribution in Thailand

NORTHERN: Phitsanulok; PENINSULAR: Phangnga.

Wider Distribution

Endemic to Thailand.

Ecology

On wet rocks in tropical evergreen forest at about 500 m alt.

Proposed IUCN Conservation Assessment

Data Deficient (DD). This species is known from two localities quite far apart in Thailand but the overall distribution and the size of the populations is uncertain.