Adiantum capillus-veneris
black maidenhair fern, common maidenhair, southern maiden-hair, southern maidenhair fern, Venus hair, Venus hair fern, Venus's-hair fern
short-creeping;
scales golden brown to medium brown, concolored, iridescent, margins entire or occasionally with single broad tooth near base.
lax-arching or pendent, closely spaced, 15–75 cm.
0.5–1.5 mm diam., glabrous, occasionally glaucous.
lanceolate, pinnate, 10–45 × 4–15 cm, glabrous, gradually reduced distally;
proximal pinnae 3(–4)-pinnate;
rachis straight to flexuous, glabrous, not glaucous.
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.
transversely oblong or crescent-shaped, 1–3(–7) mm, glabrous.
mostly 40–50 µm diam.
stalks 0.5–3.5 mm, dark color extending into segment base.
= 120.
Adiantum capillus-veneris
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 2n = 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.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
BC
CA
LA Plants
MO Plants
PNW Herbaria
SW CO Wildflowers
WildflowerSearch
iNaturalist
USDA Plants Database
