Family

Blechnaceae

Nomenclature

Blechnum orientale L., Sp. Pl. 1077. 1753; Bedd., Handb. Ferns Brit. India: 132, f. 66. 1883; Christ, Bot. Tidsskr. 24: 107. 1901; C.Chr., Bot. Tidsskr. 32: 346. 1916; C.Chr., Contr. U.S. Natl. Herb. 26: 333. 1931; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 207, f. 26.1 & 26.2 1940; Holttum, Rev. Fl. Malaya ed. 1, 2: 446, f. 262. 1955 [‘1954’]; Holttum, Dansk Bot. Ark. 20: 29. 1961; Seidenf., Nat. Hist. Bull. Siam Soc. 19: 87. 1958; Tagawa & K.Iwats., SouthE. Asian Stud. 3(3): 84. 1965; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 88. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 298. 1988; Boonkerd & Pollawatn, Pterid. Thailand: 146, 180. 2000; Dy Phon, Dictionary of Plants used in Cambodia: 95. 2000; Newman et al., Checkl. Vasc. Pl. Lao PDR: 25. 2007.

Description

Terrestrial. Rhizome thick, ascending or suberect, densely covered with scales; scales linear, gradually narrowing towards apex, 2 cm or more long, up to 2 mm broad, tailed at apex, dark brown with pale cartilaginous edges which sometimes becoming uneven. Stipes stout, stramineous, or sometimes purplish when young, up to 60 cm long, densely scaly at base, bearing small auricles (reduced pinnae) throughout. Laminae up to 2 m long, to 60 cm wide. Lateral pinnae many in number, close, 2–3 cm apart from each other, ascending, linear, gradually narrowing towards long-tailed apex, round or subtruncate at sessile base, or decurrent at posterior base and adnate in the upper ones, entire, 30 by 1.2–2 cm; veins simple or forked usually near costa, distinct on both surfaces, very close, up to 0.5 mm apart; coriaceous, green, glabrous throughout. Sori narrow, long-continuous along costa; indusia narrow, usually broken before maturity.

Distribution in Thailand

NORTHERN: Chiang Mai, Chiang Rai, Nan, Tak; NORTH-EASTERN: Loei, Udon Thani, Nong Khai; EASTERN: Chaiyaphum; SOUTH-WESTERN: Phetchaburi; CENTRAL: Nakhon Nayok; SOUTH-EASTERN: Chanthaburi, Trat; PENINSULAR: Chumphon, Ranong, Surat Thani, Phangnga, Nakhon Si Thammarat, Trang, Satun, Yala, Narathiwat.

Distribution in Laos

Attapeu, Khammouane, Luang Phrabang, Sayabouli, Vientiane.

Distribution in Cambodia

Kampot, Koh Kong.

Wider Distribution

Tropics of Asia, Australia and the Pacific, India.to Polynesia, north to southern edge of Japan (Yakushima).

Ecology

On rather dry open slopes or in light shade at low or medium altitudes throughout Thailand.

Proposed IUCN Conservation Assessment

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

Notes

This is a common species in the lowlands, variable in size and texture. In shade the plants bear broader, thinner, paler pinnae which are more spaced. The edge of the pinnae is usually inrolled, which is not unusual for plants in shade.

Voucher specimens - Thailand

Voucher specimens - Laos

Maxwell 99-205, Vientiane (CMU).

Voucher specimens - Cambodia

E.Smith 2509A, Kampot, Bokor (P); Long et al. CL506 & CL543, Koh Kong (P).