Family

Polypodiaceae

Nomenclature

Arthromeris lehmannii (Mett.) Ching, Contr. Inst. Bot. Natl. Acad. Peiping 2: 96. 1933; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 60. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 567, f. 57.3–4. 1989; Boonkerd & Pollawatn, Pterid. Thailand: 262. 2000. – Polypodium lehmannii Mett., Abhandl. Senckenb. Naturf. Ges. 2: 117, t. 3, f. 35. 1857; C.Chr., Contr. U.S. Natl. Herb. 26: 334. 1931. – Pleopeltis lehmannii (Mett.) Bedd., Ferns Brit. India: t. 260. 1868; Bedd., Handb. Ferns Brit. India: 370, f. 211. 1883.

Description

Epiphytic or lithophytic. Rhizome long creeping, about 5 mm diam., dirty brown, densely scaly throughout; scales ovate-oblong with long tails, round at peltate base, up to 7 mm long including tails about 5 mm in length, 1.5 mm broad, nearly concolorously brown or more or less paler towards margin, minutely toothed at apical portion. Stipes stramineous or pale castaneous, 10–20 cm long, glabrous. Laminae oblong, up to 45 by 40 cm, imparipinnate; rachis like the upper part of stipes; lateral pinnae 3–9 pairs, patent or slightly ascending, straight, sessile, lanceolate, caudately acuminate at apex, cuneate to round at acroscopic and round to subtruncate at basiscopic bases, up to 20 by 3 cm, subentire at wavy and more or less crisped at margin, margin with cartilaginous membrane; terminal pinna larger, about 20 cm long, like the lateral ones; main veins 3–5 mm remote, veins anastomosing copiously, more or less visible; herbaceous, green, glabrous. Sori at junction of reticulate veins, two rows between adjacent main veins, 3 or 4 rows at each side of costa, round, up to 2 mm diam., superficial .

Distribution in Thailand

NORTHERN: Chiang Mai, Chiang Rai.

Wider Distribution

Himalayas to Upper Burma, SW China, Taiwan.

Ecology

On mossy tree trunks or on mossy rocks in dense evergreen forests at high altitudes (1500–2400 m).

Similar species

Arthromeris phuluangensis Tagawa & K.Iwats.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 4885, Chiang Mai, Doi Inthanon National Park (E).