Pyrrosia porosa (C.Presl) Hovenkamp var. porosa

Family

Polypodiaceae

Nomenclature

Pyrrosia porosa (C.Presl) Hovenkamp, Blumea 30: 208. 1984; Hovenkamp, Fl. Males., Ser. II, Ferns and Fern Allies 3: 168. 1998. – Type: Wallich 266 (PRC, teste Holttum; iso B, BM, BR, K, M, P, US), India.

Pyrrosia mollis auct. non (Kunze) Ching: Tardieu & C.Chr., Fl. Indo-Chine 7(2): 506. 1941; Tagawa, J. Jap. Bot. 38: 327. 1963; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 48. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 501. 1989; Boonkerd & Pollawatn, Pterid. Thailand: 287. 2000.

Description

Rhizome creeping, bearing closely spaced fronds, up to 2.5 mm diam., densely scaly throughout; scales oblong-lanceolate, gradually narrowing towards tailed apex, 3–5(–5.7) by 0.5–2.1 mm, dark brown to nearly black in central portion, pale brown at edges; hairy at margin, thin. Fronds simple. Stipes indistinct, winged almost to base. Laminae oblanceolate, acute to acuminate at apex, gradually narrowing towards attenuate base, 9–31 by 0.7–1.2(–3.5) cm; midrib raised on lower surface, not raised on upper part of upper surface, veins hidden, anastomosing; thickly fleshy, upper surface green, hairy with downy stellate hairs or glabrescent, with scattered distinct hydathodes, lower surface densely hairy with two kinds of hairs, one with soft wavy rays, the other with long stiff brown rays. Sori scattered on the lower surface of the upper half of fronds, almost covering the whole under surface, covered with stellate hairs.

Distribution in Thailand

NORTHERN: Chiang Mai, Chiang Rai, Lampang; NORTH-EASTERN: Loei; SOUTH-EASTERN: Trat.

Distribution in Laos

Xieng Khouang.

Wider Distribution

Sri Lanka, Himalayas to SW China, Upper Burma and Indochina.

Ecology

On mossy tree trunks usually in evergreen forests at medium or high altitudes (1000–2000 m), rather common.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 4876, Chiang Mai, Doi Suthep (E); Middleton et al. 5004, Chiang Mai, Doi Chiang Dao Wildlife Sanctuary (E).

Habit

Habit

Whole plant

Whole plant

Rhizome

Rhizome

Upper surface of frond

Upper surface of frond

Hydathodes of upper frond surface

Hydathodes of upper frond surface

Lower surface of frond with young sori

Lower surface of frond with young sori

Sori

Sori

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