Asplenium inaequilaterale Willd.




Asplenium inaequilaterale Willd in L., Sp. Pl., ed. 4, 5: 322.1810; Sledge, Bull. Brit. Mus. Nat. Hist. (Bot.) 3, 6: 252. 1965; Schelpe & N.C.Anthony in Fl. S. Africa (Pteridophyta ): 191. f. 63:1. 1986; Philcox, Revis. Handb. Fl. Ceylon XV(A): 15. 2006; Boonkerd, ScienceAsia 35: 386. 2009.


Description from Boonkerd, ScienceAsia 35: 386. 2009 for two Thai specimens.
Lithophytic. Rhizome erect to suberect, about 1 cm in diam., apex clothed with scales, scales about 1 mm long by 0.35 mm wide, ovate-lanceolate to sublinear, acuminate, entire, dark-brown centrally, paler at margin. Stipes 12–12.7 cm long, pale to greenish brown, tufted, rounded below, grooved above, glabrous to sparsely pubescent; rachis similar, glabrous. Laminae 18–21.6 x 4.2–5 cm, oblong to oblong-lanceolate in outline, pinnate, apex lobed. Pinnae herbaceous, dark-green, glabrous, up to 20(–25) pairs, pinnae subopposite or alternate, about 1 cm distant, basal pinnae slightly or not reduced in size, 2.0–2.5 x 0.8–1.0 cm, trapezoid-lanceolate, dimidiate, acroscopic base truncate, subparallel to rachis, basiscopic base obliquely excised to about half the length of pinna, acute or subacute, margin incised-crenate or serrate throughout, glabrous. Veins free, forked, nearly reaching the margin. Sori 2–4(–6) pairs, 4–5 x 1.5 mm, mostly midway on veins; indusium membranous, entire .

Distribution in Thailand

NORTHERN: Mae Hong Son.

Wider Distribution

S. Africa, Mascarenes, S. India and Sri Lanka.


On rocks in streams at 1550 m altitude.

Proposed IUCN Conservation Assessment

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

Site hosted by the Royal Botanic Garden Edinburgh. Content managed by Stuart Lindsay, Gardens by the Bay, Singapore and David Middleton, Singapore Botanic Gardens. Last updated 24 January 2012