Pteris asperula J.Sm. ex Hieron.

Family

Pteridaceae, subfamily Pteridoideae

Nomenclature

Pteris asperula J.Sm. ex Hieron., Hedwigia 55: 362. 1914; Holttum, Rev. Fl. Malaya ed. 1, 2: 406, f. 236. 1955 [‘1954’]; Holttum, Dansk. Bot. Ark. 23: 235. 1965; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 80. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 252, f. 20.3. 1985; Boonkerd & Pollawatn, Pterid. Thailand: 105, 126. 2000.

Description

Rhizome short creeping, bearing fronds close to each other; scales linear, up to 4 by 0.2 mm, brown with pale ferrugineous margin. Stipes about 50 cm long, castaneous and scaly at base, stramineous or pale castaneous upwards, glabrescent. Laminae about 40 by 30 cm, oblong in outline, acute at apex, deeply bipinnatifid; lateral pinnae 7–8 pairs, opposite, ascending and slightly falcate, up to 20 by 2.5–4.5 cm, basal pinnae the largest, bearing basal basiscopic pinnules like upper lateral pinnae; upper pinnae becoming smaller upwards; rachis and costa grooved on upper surface, sparsely hairy, pale castaneous or slightly purplish; pinnules very narrowly oblong, rounded at apex, decurrent to the next ones by wings of costa about 1 mm broad, 15–25 by 2.5–4 mm, papyraceous, green; veins forked, distinct on both surfaces. Sori along margin of pinnules almost from base to apex; indusia membranous, transparent .

Distribution in Thailand

NORTHERN: Phitsanulok; SOUTH-WESTERN: Kanchanaburi, Phetchaburi; PENINSULAR: Phangnga, Satun.

Wider Distribution

Throughout Malesia.

Ecology

On rather dry banks of mountain paths in open areas at about 400 m alt.

Proposed IUCN Conservation Assessment

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

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