Family

Thelypteridaceae

Nomenclature

Cyclosorus triphyllus (Sw.) Tardieu ex Tardieu & C.Chr., Notul. Syst. 7: 77. 1938; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 386. 1941. – Meniscium triphyllum Sw., Schrad. J. Bot. 1800(2): 16. 1801; Bedd., Handb. Ferns Brit. India: 397, f. 231. 1883; Christ, Bot. Tidsskr. 24: 109. 1901. – Dryopteris triphylla (Sw.) C.Chr., Index Filic.: 298. 1905; C.Chr., Bot. Tidsskr. 32: 343. 1916; Seidenf., Nat. Hist. Bull. Siam Soc. 19: 87. 1958. – Abacopteris triphylla (Sw.) Ching, Bull. Fan Mem. Inst. Biol. 8: 241. 1938; Holttum, Rev. Fl. Malaya ed. 1, 2: 287, f. 166. 1955 [‘1954’]. – Thelypteris triphylla (Sw.) K.Iwats., Mem. Coll. Sci. Univ. Kyoto B. 31: 190. 1965; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 70. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 414. 1988. – Pronephrium triphyllum (Sw.) Holttum, Blumea 20: 122. 1972; Holttum, Fl. Males., Ser. II, Pterid. 1: 534, f. 16k–l. 1982 [‘1981’]; Boonkerd & Pollawatn, Pterid. Thailand: 167, 168, 228. 2000. – Type: China (S-PA).

var. triphyllus

Description

Rhizome long creeping, 2–3 mm diam.; scales narrow, up to 5 by 0.6 mm, brown, hairy. Stipes remote, up to 50 cm long, stramineous with dark scaly base, hairy. Laminae with 1( –2) pair(s) of lateral pinnae; terminal pinna larger, oblong-lanceolate, caudate-acuminate at apex, rounded to cuneate at base, up to 11.5–25 by 2–5 cm, subentire or irregularly undulate; lateral pinnae more or less falcate, caudate at apex, cuneate to round at base, 4–15 by 1.2–2.5 cm; venation meniscioid, hairy; texture herbaceous to thinly papyraceous, deep green, often tinted red in dried specimens. Sori elongate along united veinlets, crescent-shaped, naked; sporangia setiferous.

Distribution in Thailand

NORTHERN: Chiang Rai, Phitsanulok; NORTH-EASTERN: Loei, Nong Khai; CENTRAL: Nakhon Nayok; SOUTH-EASTERN: Chon Buri, Chanthaburi, Trat; PENINSULAR: Ranong, Phangnga, Nakhon Si Thammarat, Narathiwat.

Distribution in Laos

Savannakhet.

Wider Distribution

Tropics of Asia to Australia, north to southern edge of Japan.

Ecology

On dry banks of rivers in shade at low altitudes.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 5533, Nakhon Si Thammarat, Khao Luang National Park (E).

Voucher specimens - Laos

Maxwell 07-345, Savannakhet (CMU)