Family

Aspleniaceae

Nomenclature

Asplenium nidus L., Sp. Pl. 1079. 1753; E.Smith, J. Siam Soc. Nat. Hist. Suppl. 8: 4. 1929; C.Chr., Contr. U.S. Natl. Herb. 26: 332. 1931; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 219. 1940; Holttum, Rev. Fl. Malaya ed. 1, 2: 419. 1955 [‘1954’]; Holttum, Dansk Bot. Ark. 20: 28. 1961; Holttum, Dansk Bot. Ark. 23: 236. 1965; Gard. Bull. Singapore 27: 147. 1974; Tagawa & K.Iwats., SouthE. Asian Stud. 3(3): 84. 1965; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 83. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 266. 1985; Boonkerd & Pollawatn, Pterid. Thailand: 110, 142. 2000; Newman et al., Checkl. Vasc. Pl. Lao PDR: 25. 2007. – Neottopteris nidus (L.) J.Sm., J. Bot. 3: 409. 1841. – Thamnopteris nidus (L.) C.Presl, Epimel. Bot.: 68. 1851 [‘1849’]; Bedd., Handb. Ferns Brit. India: 137. 1883.

Two varieties are recognised in Thailand

Asplenium nidus L. var. nidus

And

Asplenium nidus L. var. musifolium (Mett.) C.Chr., Index Filic.: 122. 1905; Holttum, Rev. Fl. Malaya ed. 1, 2: 419. 1955 [‘1954’]; Tagawa & K.Iwats., Fl. Thailand 3: 267. 1985; Boonkerd & Pollawatn, Pterid. Thailand: 142. 2000; Newman et al., Checkl. Vasc. Pl. Lao PDR: 25. 2007. – Asplenium musifolium Mett., Farngatt. 6: 86. 1859; Holttum, Gard. Bull. Singapore 27: 149. 1974; Newman et al., Checkl. Vasc. Pl. Lao PDR: 25. 2007. – Thamnopteris nidus (L.) C.Presl var. musifolia (Mett.) Bedd., Handb. Ferns Brit. India: 139. 1883.

Description

Epiphytic or lithophytic. Rhizome short, erect or ascending, stout, bearing a rosette of fronds, usually with a mass of roots on which are growing various epiphytes, scaly; scales brown to darker, membranous, up to 2 cm long, 3 mm broad, clathrate. Stipes stramineous to dark, 2–5 cm long, scaly at base. Frond simple, up to 110 cm or more long, 12–30 cm broad (but occasionally narrower, about 6 cm broad in soriferous ones), broadest at middle, gradually narrowing towards both apex and base, coriaceous, grass-green when living, paler below; midrib raised on upper surface, flat below, veins once or rarely twice forked, the first forking near midrib and then running parallel, uniting at apex to form submarginal veins about 0.5 mm inside leaf margin. Sori elongate along veins, extending from near midrib half-way to the margin, usually on every vein; indusia about 0.5 mm broad, with a space of 0.5 mm or wider between.

The two varieties of Asplenium nidus in Thailand can be distinguished thus:

1. Frond up to 20 cm wide; apex gradually attenuate ...a. var. nidus

1. Frond up to 30 cm wide; apex broadly rounded ... b. var. musifolium

Distribution in Thailand

For Asplenium nidus var. nidus: NORTHERN: Chiang Mai, Chiang Rai, Lampang; NORTH-EASTERN: Loei, Nong Khai; SOUTH-WESTERN: Kanchanaburi; CENTRAL: Saraburi; SOUTH-EASTERN: Chon Buri, Chanthaburi, Trat; PENINSULAR: Surat Thani, Phangnga, Krabi, Nakhon Si Thammarat.

For Asplenium nidus var. musifolium: SOUTH-WESTERN: Prachuap Khiri Khan; PENINSULAR: Nakhon Si Thammarat.

Distribution in Laos

For Asplenium nidus var. nidus: Khammouane, Vientiane.

For Asplenium nidus var. musifolium: Unspecified.

Distribution in Cambodia

Wider Distribution

For Asplenium nidus var. nidus: Throughout the Old World tropics.

For Asplenium nidus var. musifolium: W Malesia.

Ecology

Usually on tree-trunks or on rocks in dense forests or under heavy crowns of trees in light shade at various altitudes below 2000 m.

Similar species

Asplenium phyllitidis D.Don.

Proposed IUCN Conservation Assessment

Least Concern (LC). Both varieties are widespread and not under any known threats.

Notes

This is a common species throughout Southeast Asia and very variable though no practical classification has yet been given.

Voucher specimens - Laos

Maxwell 99-193, Vientiane (CMU).