Family

Aspleniaceae

Nomenclature

Asplenium exiguum Bedd., Ferns S. India: 49, t. 146. 1863; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 234. 1940; Tagawa & K.Iwats., Acta Phytotax. Geobot. 23: 112. 1968; Tagawa & K.Iwats., Fl. Thailand 3: 290, f. 23.3. 1985; Boonkerd & Pollawatn, Pterid. Thailand: 140. 2000.

Description

Lithophytic. Rhizome short creeping, bearing fronds very close together or nearly in a tuft; scales narrowly lanceolate, gradually narrowing towards hair-pointed apex, up to 7 by 0.6 mm, dark brown to nearly black, clathrate, entire. Stipes castaneous to purplish, polished, bearing linear scales when young, up to 5 cm long, often bearing pinnae nearly to the base, grooved above. Laminae narrowly lanceolate, attenuate towards both ends, up to 20 by 2.5 cm, pinnate; lateral pinnae about 20 pairs, the middle ones the largest, stalked, oblong, patent, rounded at apex, auricled at acroscopic and cuneate at basiscopic bases, variously lobed, about 6 by 2 mm, the lower ones reflexed and the upper ones ascending; rachis paler or stramineous, grooved above, glabrescent, grooved above; segments of pinnae usually oblique, narrowly subdeltoid, rounded to obtuse and toothed at apex, separated by broad sinus, thinly papyraceous, glabrous; midrib indistinct, veins hardly visible, simple to a few times forked; bulbils at frond apex, sometimes with an extended rachis, usually also with a bulbil on pinnae apices, occasionally also with a bulbils on a pinnule apex. Sori one to several on each pinna, 1–2 mm long, usually confluent at maturity occupying the whole under surface of pinna; indusia pale, firm, entire .

Distribution in Thailand

NORTHERN: Chiang Mai.

Wider Distribution

S India, Himalaya to China, N Vietnam, Taiwan and the Philippines.

Ecology

On moist mossy limestone cliffs in thicket at 1450–2100 m.

Similar species

Asplenium laciniatum D.Don

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 4987, Chiang Mai, Doi Chiang Dao Wildlife Sanctuary (E); Middleton et al. 5027 & 5029, Chiang Mai, Doi Ang Khang (E).