Adiantum littoraleJenman [family PTERIDACEAE ] (stored under name); Adiantum tenerum(Jenman) Domin [family PTERIDACEAE ] Verified by William Ralph Maxon, Adiantum tenerumSw. [family PTERIDACEAE ] Verified by George Samuel Jenman,
Related name
Adiantum capillus-veneris
Adiantum extensum
Adiantum dilatatum
Adiantum andicola
Adiantum floridanum
Adiantum raddianum
Adiantum littorale
Adiantum trapeziforme
Adiantum tenerum
Adiantum trapezoides
Common name
Brittle maidenhair, Flora of North America Vol. 2
Flora
Entry for Adiantum tenerum Swartz [family ADIANTACEAE]
Stems short-creeping; scales bicolored, centers dark reddish brown, margins pale tan, erose-ciliate. Leaves arching or sometimes pendent, closely spaced, 20--110 cm. Petiole 1--3 mm diam., glabrous, occasionally glaucous. Blade trowel-shaped, pinnate, 12--60 × 12--60 cm, gradually reduced distally, glabrous; proximal pinnae 3-pinnate; rachis straight, glabrous, not glaucous. Segment stalks 1--5 mm, with dark color ending abruptly at segment base, terminating in cupulelike swelling at base of segment (unlike any other species of Adiantum in the flora). Ultimate segments fan-shaped or rhombic, about as long as broad; base cuneate; apex rounded or acute, lobed, lobes separated by narrow incisions 0.5 mm wide. Indusia transversely oblong to crescent-shaped, 0.5--2 mm, glabrous. Spores mostly 40--58 µm diam. 2 n = 60.
Phenology
Sporulating throughout the year
Altitude range
0--50 m
Distribution
es MexicoCentral America in GuatemalaHondurasNicaraguaCosta RicaSouth America in Venezuela.USA Fla.
Discussion
Adiantum tenerum is readily distinguished from other species in the flora by the ultimate segments conspicuously articulate to the stalks.