Family

Athyriaceae

Nomenclature

Diplazium tomentosum Blume, Enum. Pl. Javae.: 192. 1828; Bedd., Handb. Ferns Brit. India: 179. 1883; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 257. 1940; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 103. 1967; Tagawa & K.Iwats., Fl. Thailand 3: 457. 1988; Boonkerd & Pollawatn, Pterid. Thailand: 155, 197. 2000. – Athyrium tomentosum (Blume) Milde, Bot. Zeit. 1870: 354. 1870; Holttum, Rev. Fl. Malaya ed. 1, 2: 551, f. 324. 1955 [‘1954’].

Description

Rhizome short, erect or ascending, bearing wiry roots; scales narrow, up to 4 by 0.6 mm, concolorous, dark brown, subentire or irregularly waved at margin. Stipes stramineous with dark castaneous lower portion, up to 35 cm long on soriferous fronds and 15 cm on sterile ones. Frond pinnate-bipinnatifid, oblong-subdeltoid, attenuate at apex, with deflexed basal pinnae, up to 30 by 12 cm; rachis densely covered with short coarse multicellular hairs with brown septae; lowest pinnae deflexed, lanceolate, shortly stalked, auricled at acroscopic base, up to 7 by 2 cm; lower and middle pinnae shortly stalked, patent, acute to acuminate at apex, auricled at acroscopic and rounded to cuneate at basiscopic bases, lobed 1/5–2/3 way to costa, upper pinnae sessile to adnate at base; lobes oblique, oblong, moderately acute at apex, toothed, up to 10 by 4 mm; chartaceous, deep green, dark when dry, veins pinnate, veinlets simple or forked. Sori on practically all veinlets of tall soriferous frond, usually only on basal acroscopic veinlets; indusia firm, persistent .

Distribution in Thailand

SOUTH-EASTERN: Chanthaburi, Trat; PENINSULAR: Ranong, Surat Thani, Krabi, Nakhon Si Thammarat, Trang, Yala, Narathiwat.

Wider Distribution

Burma (Tenessarim), Peninsular Malaysia, Vietnam, Sumatra, Java, Borneo, and Mindanao.

Ecology

On mountain slopes in dense evergreen forests at altitudes below 800 m alt.

Proposed IUCN Conservation Assessment

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