Family

Osmundaceae

Nomenclature

Osmunda angustifolia Ching, Acta Phytotax. Sin. 8: 131, 160, f. 10. 1959; Fl. Reipubl. Popularis Sin. 2: 84. 1959; Tagawa & K.Iwats. SouthE. Asian Stud. 5: 34. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 45. 1979; Boonkerd & Pollawatn, Pterid. Thailand: 31, 77. 2000.

Description

Fronds congested at apex of rhizome. Stipes stramineous, short, up to 25 cm long; laminae pinnate with a distinct apical pinna, moderately acute at apex, a few pairs of basal pinnae slightly shortened; lateral pinnae linear, gradually narrowing both towards acute apex and towards shortly stalked base, less than 15 cm long, 1.2 cm broad, the margin slightly waved, the sinus usually less than 1 mm in depth; the veins two or three times dichotomously branching; texture papyraceous to softly coriaceous, fresh green in colour; a few middle pinnae fertile, contracted , brown after shedding the spores.

Distribution in Thailand

NORTH-EASTERN: Phetchabun, Loei; SOUTH-EASTERN: Trat.

Distribution in Laos

Vientiane.

Wider Distribution

Hainan, Hongkong, China (Guangdong) and Taiwan (?)

Ecology

On sandy banks or on wet rocks usually along streams in dense forest or in half shaded areas at medium altitude.

Proposed IUCN Conservation Assessment

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

Voucher specimens - Laos

Munzinger 78, Vientiane, Montagne du Boeuf sacre (P).