Family

Athyriaceae

Nomenclature

Athyrium anisopterum Christ, Bull. Herb. Boiss. 6: 962. 1898; Tagawa & K.Iwats., Acta Phytotax. Geobot. 23: 116, f. 12. 1968; Tagawa & K.Iwats., Fl. Thailand 3: 448. 1988; Boonkerd & Pollawatn, Pterid. Thailand: 188. 2000.

Athyrium macrocarpum auct. non (Blume) Bedd.: Holttum, Rev. Fl. Malaya ed. 1, 2: 550, f. 323. 1955 [‘1954’].

Description

Terrestrial. Rhizome short, ascending, scaly; scales narrow and subulate, up to 8 by 1 mm, entire, tailed at apex, more or less bicoloured. Stipes up to 12 cm long, stramineous, dark and scaly at base. Laminae narrowly oblong, acuminate to attenuate at apex, up to 20 by 6 cm, pinnate-bipinnatifid; pinnae stalked, patent or deflexed in lower ones, oblong to oblong-subdeltoid, rounded to acute at apex, auricled at acroscopic and cuneate to dimidiate at basiscopic bases, up to 35 by 1.2 mm, lobed nearly 1/2 way towards costa; lobes rounded, toothed; papyraceous, minutely scaly on rachis and costa. Sori medial, round, rather large; indusia round to oblong, opening outwards, more than 1 mm wide, crenate to lacerate at margin .

Distribution in Thailand

NORTHERN: Chiang Mai.

Wider Distribution

Sri Lanka, S India, Himalaya, Burma, SW China (Yunnan and Guangdong), Taiwan, Malaysia, Borneo and Luzon.

Ecology

On humus-rich floor of dense evergreen forests above 1800 m alt.

Proposed IUCN Conservation Assessment

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

Notes

The Lao material of Athyrium macrocarpum var. atkinsonii mentioned in Tardieu & Christensen, Fl. Indo-Chine (but incorrectly said to be from Cambodia) has been redetermined to Athyrium anisopterum in the Paris herbarium but is neither Athyrium macrocarpum, Athyrium macrocarpum var. atkinsonii nor Athyrium anisopterum.  Athyrium is in great need of revision in SE Asia and we have so far been unable to identify the Lao material.  We refrain from describing it as new pending more comprehesive research.