Stems short-creeping; scales golden brown to medium brown, concolored, iridescent, margins entire or occasionally with single broad tooth near base. Leaves lax-arching or pendent, closely spaced, 15--75 cm. Petiole 0.5--1.5 mm diam., glabrous, occasionally glaucous. Blade lanceolate, pinnate, 10--45 × 4--15 cm, glabrous, gradually reduced distally; proximal pinnae 3(--4)-pinnate; rachis straight to flexuous, glabrous, not glaucous. Segment stalks 0.5--3.5 mm, dark color extending into segment base. Ultimate segments various, generally cuneate or fan-shaped to irregularly rhombic (plants in American southwest occasionally with segments nearly round), about as long as broad; base broadly to narrowly cuneate; margins shallowly to deeply lobed, incisions 0.5--7 mm, occasionally ± laciniate, sharply denticulate in sterile segments; apex rounded to acute. Indusia transversely oblong or crescent-shaped, 1--3(--7) mm, glabrous . Spores mostly 40--50 µm diam. 2 n = 120. Sporulating spring--summer. Moist calcareous cliffs, banks, and ledges along streams and rivers, walls of lime sinks, canyon walls (in the American southwest), around foundations, on mortar of storm drains; 0--2500 m; B.C.; Ala., Ariz., Ark., Calif., Colo., Fla., Ga., Ky., La., Miss., Mo., Nev., N.Mex., N.C., Okla., S.C., S.Dak., Tenn., Tex., Utah, Va.; Mexico; West Indies; Central America; South America in Venezuela, Peru; tropical to warm temperate regions in Eurasia and Africa. No evident pattern to morphologic variation in the species is discernible, although a number of segregate species and infraspecific taxa have been recognized within North American Adiantum capillus-veneris . In the Eastern Hemisphere, the species is diploid, with 2 n = 60 (I. Manton 1950). Several tetraploid counts have been reported from North America (W. H. Wagner Jr. 1963). Spore-measurement data suggest, however, that the polyploid cytotype may not be widely distributed. Further investigation is needed to determine whether Adiantum capillus-veneris populations in North America are conspecific with those in Eurasia and Africa.
General: Short creeping stems, with golden brown to medium brown scales, iridescent with entire or with a single tooth near the base; numerous fronds lax-arching or pendent, closely spaced, 15-75 cm in length. Leaves: Blade ovate-lanceolate and pinnate, 10-45 cm long by 4-15 cm wide, gradually reduced above; each pinnule on stalks 0.5-3.5 mm dark colored extending into segment base; ultimate pinnules generally cuneate to fan-shaped to irregularly rhombic, about as long as broad, base broadly to narrowly cuneate; margins shallowly lobed to deeply incised on outer margins, apex rounded to acute. Sporangia: Indusia transversely oblong or crescent-shaped, 1-3 mm, glabrous. Ecology: Found on moist sites, usually along cliffs or wet, rocky banks, often in limestone from 1,500-7,000 ft (457-2134 m); sporulates spring-summer. Notes: Distinctive with its delicate fan-shaped pinnules at the end of stalks which are often a dark purple along water. Ethnobotany: Used for rheumatism, as a lotion for bee and centipede stings, and the plant is taken as a cure for insanity. Etymology: Adiantum is from Greek adiantos meaning unwetted or unwettable, while capillus-veneris is from Greek words for hair and Venus. Sources: FNA 1993, Dittmer et al. 1954, Kearney and Peebles 1969