Abrodictyum obscurum (Blume) Ebihara & K.Iwats. var. siamense (Christ) K.Iwats.

Family

Hymenophyllaceae

Nomenclature

Abrodictyum obscurum (Blume) Ebihara & K.Iwats. var. siamense (Christ) K.Iwats., Blumea 51(2): 244. 2006. – Trichomanes siamense Christ, Bot. Tidsskr. 24: 103. 1901; C.Chr., Bot. Tidsskr 32: 417. 1916. – Selenodesmium siamense (Christ) Ching & Wang, Acta Phytotax. Sin. 8: 138. 1959; Ching, Fl. Reipubl. Popularis Sin. 2: 191, pl. 15, f. 6–7. 1959. – Cephalomanes obscurum var. siamense (Christ) K.Iwats., Fac. Sci. Univ. Tokyo, Sect. 3, Bot. 13: 548. 1985; Tagawa & K.Iwats., Fl. Thailand 3: 615. 1989; Boonkerd & Pollawatn, Pterid. Thailand: 68. 2000.

Description

Terrestrial or lithophytic. Rhizome very short, creeping or ascending, bearing many wiry roots and stipes, covered with dark hairs, 1–1.2 mm diam. Stipes stiff, stramineous, winged in upper parts, covered with brownish hairs, the hairs dense at base. Fronds oblong-subdeltoid or oblong-ovate, gradually narrowing towards acute apices, broadly cuneate or subtruncate at base, tripinnatifid, or more finely dissected; rachis winged, pinnae with very short stalks, oblong-lanceolate, acute at apex, cuneate at base; pinnules with several segments, the base decurrent to form narrow wings of costae; texture coarse, dark green in colour. Sori apical on apical segments, cup-shaped, winged, the mouth more or less dilated.

Distribution in Thailand

SOUTH-EASTERN: Trat.

Wider Distribution

China (Guangxi, Guangdong, Hainan), Cambodia, and the Ryukyus.

Ecology

Terrestrial on wet sandy ground or in muddy crevices of wet rocks usually near stream in deep shade.

Proposed IUCN Conservation Assessment

Least Concern (LC). Widespread and not under any immediate known threat.

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 16 November 2016.