Etymology

According to Holttum (1954), the botanical name, Adiantum (unwetted) refers to the way in which water-drops run off the surface of the pinnae without wetting them.

Family

Pteridaceae, subfamily Vittarioideae

Nomenclature

Adiantum capillus-veneris L., Sp. Pl. 1096. 1753; Bedd., Handb. Ferns Brit. India: 84. 1883; Tardieu & C.Chr., Fl. Indo-Chine 7(2): 185. 1940, cum var. laciniatum; Holttum, Rev. Fl. Malaya ed. 1, 2: 600, f. 352. 1955 [‘1954’]; Holttum, Dansk Bot. Ark. 23: 244. 1965; Tagawa & K.Iwats., Fl. Thailand 3: 214. 1985; Boonkerd & Pollawatn, Pterid. Thailand: 117. 2000. – Type: South Europe, France, Without data, Magnol s.n. (lectotype : LINN 1252.9). Lectotypified by Pichi-Sermolli, Webbia 12: 678. 1957.

Description

Lithophytic. Rhizome short creeping, densely covered with scales; scales entire, narrow, brown, 1.5–3 mm long, 0.3–0.5 mm wide. Stipes bright blackish-purple to nearly black, glabrous except sparsely scaly basal part, 3–8(–20) cm long. Laminae oblong-subdeltoid or narrower, round at apex, 5–18(–25) by 3–8(–16) cm, bipinnate; rachis slender, not prolonged, perfectly glabrous throughout; pinnae 3–5 pairs of pinnate pinnae, up to 9 including simple ones, distinctly stalked, basal ones the largest, with a few pairs of leaflets, subtriangular, cuneate at base, 2–7(–9) by 1.5–4 cm, the upper with a single leaflet almost the same as those of basal pinnae; leaflets with short but distinct stalks, fan-shaped, up to 1.5 cm long and wide; two basal edges entire, straight or a little recurved, forming less than right-angle; distal margin round, more or less lobed, sinus shallow or to almost the base of leaflets; lobes round, oblong or spathulate, round or subtruncate at subentire to toothed apex, softly herbaceous, or thinner; veins dichotomous, not raised, glabrous throughout. Sori round or a little elongate .

Distribution in Thailand

NORTHERN: Chiang Mai, Lampang, Phrae, Tak; NORTH-EASTERN: Loei; SOUTH-WESTERN: Kanchanaburi, Prachuap Khiri Khan; CENTRAL: Saraburi; PENINSULAR: Chumphon.

Distribution in Laos

Khammouane.

Wider Distribution

Tropical, subtropical, and warm temperate regions throughout the world.

Ecology

In muddy crevices of limestone cliffs or on mossy rocks by streams usually in spray in light shade at low altitudes.

Proposed IUCN Conservation Assessment

Least Concern (LC). This species is common and widespread.

Voucher specimens - Thailand

Van Beusekom et al. 4668, Phrae, Mae Khaem (P); Middleton et al. 4741, Kanchanaburi, Lam Khlong Ngu National Park (E).

Voucher specimens - Laos

Petelot s.n., Khammouane, Mahaxay (P).