Hymenasplenium excisum (C.Presl) S.Linds.

Family

Aspleniaceae

Nomenclature

Hymenasplenium excisum (C.Presl) S.Linds., Thai Forest Bull., Bot. 37: 69. 2009. – Asplenum excisum C.Presl, Epimel. Bot.: 74. 1851 [‘1849’]; Holttum, Rev. Fl. Malaya ed. 1, 2: 439, f. 256. 1955 [‘1954’]; Holttum, Dansk Bot. Ark. 20: 28. 1961; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 84. 1967; K.Iwats., Acta Phytotax. Geobot. 27: 49. 1975; Tagawa & K.Iwats., Fl. Thailand 3: 278. 1985; Boonkerd & Pollawatn, Pterid. Thailand: 140. 2000. – Type: Philippines, Cuming 110 (E).

Asplenium unilaterale f. majus C.Chr., Bernice P. Bishop Mus. Bull. 177: 67. 1943. – Asplenium unilaterale var. majus (C.Chr.) Sledge, Bull. Brit. Mus. (Nat. Hist.) Bot. 3: 246. 1965.

Asplenium unilaterale auct. non Lam.: Tardieu & C.Chr., Fl. Indo-Chine 7(2): 224. 1940, p.p.

Description

Similar to Hymenasplenium apogamum (N.Murak. & Hatan.) Nakaike but different from it in: plants 30–40 cm long, 7–18 cm wide; pinnae larger, gradually becoming smaller upwards, the largest ones shortly stalked, a little falcate, up to 9 by 2 cm, acuminate at apex .

Distribution in Thailand

NORTHERN: Chiang Mai, Lampang, Tak, Phitsanulok; CENTRAL: Nakhon Nayok; SOUTH-EASTERN: Chanthaburi; PENINSULAR: Satun.

Distribution in Laos

Champasak.

Distribution in Cambodia

Unspecified.

Wider Distribution

Tropical Africa, Sri Lanka, S India, Himalaya, throughout Malesia to Polynesia and Hawaii, north to Vietnam, S China, Taiwan and the Ryukus.

Ecology

On wet ground or on wet muddy rocks usually along streams in dense forests at 300–1500 m alt.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Thailand

Middleton et al. 5037, Chiang Mai, Doi Ang Khang (E); Middleton et al. 5352, Satun, Thale Ban National Park (E).

Voucher specimens - Laos

Poilane 28364, Champasak, Pakson (P).

Habit

Habit

Rhizome

Rhizome

Rhizome apex with scales

Rhizome apex with scales

Frond from beneath

Frond from beneath

Lower surface of lamina

Lower surface of lamina

Upper surface of lamina

Upper surface of lamina

Frond apex

Frond apex

Pinnae

Pinnae

Pinnae with mature sori

Pinnae with mature sori

Young sori

Young sori

Site hosted by the Royal Botanic Garden Edinburgh. Content managed by Stuart Lindsay, Gardens by the Bay, Singapore and David Middleton, Singapore Botanic Gardens. Last updated 24 January 2012