Family

Lindsaeaceae

Nomenclature

Lindsaea heterophylla Dryand., Trans. Linn. Soc. 3: 41, pl. 8 f. 1. 1797; Bedd., Handb. Ferns Brit. India: 77. 1883; Christ, Bot. Tidsskr. 24: 110. 1901; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 75. 1967; Kramer, Fl. Males., Ser. II, Pterid. 1: 210, f. 17 & 18. 1971; Kramer, Gard. Bull. Singapore 26: 31. 1972; Tagawa & K.Iwats., Fl. Thailand 3: 132. 1985; Boonkerd & Pollawatn, Pterid. Thailand: 92. 2000. – Schizoloma heterophyllum (Dryand.) J.Sm., J. Bot. 3: 414. 1841; Bedd., Handb. Ferns Brit. India: 80. 1883; C.Chr., Bot. Tidsskr. 32: 345. 1916; Holttum, Rev. Fl. Malaya ed. 1, 2: 345. 1955 [‘1954’]; Ching, Fl. Reipubl. Popularis Sin. 2: 273. pl. 23, f. 7–11. 1959.

Description

Rhizome short creeping, bearing fronds close together, about 5 mm diam., densely scaly at apex; scales linear, up to 2.5 mm in length, 2–3 cells broad at base, brown, more or less bright. Stipes brown to purplish, paler above, scaly at base, grooved on upper surface, round beneath, up to 30 cm long. Laminae simply pinnate to bipinnate, up to 25 by 20 cm; lower pinnae pinnate, linear-subtriangular to narrowly subdeltoid, stalked; upper pinnae simple, subsessile, linear-lanceolate with entire margin, acuminate at apex, cuneate to subtruncate at base; pinnules larger ones like the upper pinnae; smaller ones fan-shaped or ovate, entire, all herbaceous, green; veins anastomosing to form a row of areoles at each side of costa, otherwise free except for those united by sori. Sori continuous, not interrupted; indusia firm, hardly reaching the margin of pinnae or pinnules.

Distribution in Thailand

NORTHERN: Chiang Mai; NORTH-EASTERN: Loei; SOUTH-EASTERN: Trat; PENINSULAR: Surat Thani.

Wider Distribution

Madagascar, S India, Sri Lanka, Indochina, S China, W and N Central Malesia, north to the Ryukyus.

Ecology

On rather dry slopes in evergreen forests, not in open areas, at various altitudes: from sea level to about 1200 m.

Proposed IUCN Conservation Assessment

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

Notes

This species is variable in pinnation, size and form of plants and in texture. In light shade the plants become smaller with small pinnae, less divided and rather thick in texture, venation is rarely anastomosing in such small plants.

Voucher specimens - Thailand

Middleton et al. 4598, Trat, Ko Chang, Thanmagon Waterfall (E).