Adiantum viridimontanum

Paris

Rhodora 93: 108. 1991.

Common names: Green Mountain maidenhair
Endemic
Treatment appears in FNA Volume 2.

Stems short-creeping; scales bronzy deep yellow, concolored, margins entire. Leaves arching to stiffly erect, often densely clustered, 38–75 (–90) cm. Petiole 1–3 mm diam., glabrous, often glaucous. Blade fan-shaped to funnel-shaped, pseudopedate, 1-pinnate distally, 10–35 × 10–35 (–45) cm, glabrous; proximal pinnae 2–7-pinnate; rachis straight, glabrous, often glaucous. Segment stalks (0.4–) 0.6–1.5 (–1.9) mm, dark color commonly entering into segment base. Ultimate segments long-triangular, ca. 2.5 times as long as broad; basiscopic margin oblique; acroscopic margin lobed, lobes separated by narrow (less than 1 mm) incisions; apex acute, usually entire. False indusia transversely oblong, mostly 2–5 (–10) mm, glabrous. Spores mostly 45–58 µm diam. 2n = 116.


Phenology: Sporulating summer–fall.
Habitat: Restricted to serpentine sites where it occurs in rock clefts, on talus slopes, and in well-developed serpentine soils
Elevation: 200–800 m

Discussion

Adiantum viridimontanum, an allopolyploid from a sterile hybrid between A. pedatum and A. aleuticum, is known only from north central Vermont (C. A. Paris and M. D. Windham 1988). Additional populations may eventually be located on serpentine in southern Quebec.

Selected References

None.

Lower Taxa

None.
... more about "Adiantum viridimontanum"
Cathy A. Paris +
truncate +  and cuneate +
pseudopedate +
35 cm350 mm <br />0.35 m <br /> (45 cm450 mm <br />0.45 m <br />) +
10 cm100 mm <br />0.1 m <br /> (35 cm350 mm <br />0.35 m <br />) +
fan-shaped +  and funnel-shaped +
membranaceous;papery +
10 cm100 mm <br />0.1 m <br /> (35 cm350 mm <br />0.35 m <br />) +
Green Mountain maidenhair +
200–800 m +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
yellow +  and white +
obcordate;reniform +
Restricted to serpentine sites where it occurs in rock clefts, on talus slopes, and in well-developed serpentine soils +
monomorphic +
densely clustered;closely spaced +
75 cm750 mm <br />0.75 m <br /> (90 cm900 mm <br />0.9 m <br />) +
recurved +  and reflexed +
arching +  and stiffly erect +
noncircinate +  and circinate +
38 cm380 mm <br />0.38 m <br /> (75 cm750 mm <br />0.75 m <br />) +
dentate +, erose-ciliate +  and entire +
acroscopic +  and basiscopic +
chestnut-brown;dark purple or blackish +
glaucous +  and glabrous +
Sporulating summer–fall. +
glaucous +  and glabrous +
concolored;yellow;bronzy +
persistent +
linear-lanceolate +  and lanceolate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.19 cm1.9 mm <br />0.0019 m <br />) +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
yellowish-brown +  and yellow +
1 +, 32 +  and 64 +
tetrahedral-globose +
suberect +  and long-creeping +
shiny +  and dull +
Adiantum viridimontanum +
Adiantum +
species +
2.5 times as long as broad +
0.3 cm3 mm <br />0.003 m <br /> (?) +  and 2.9 cm29 mm <br />0.029 m <br /> (?) +
1 +  and several +
crescent--shaped +  and roundish +
anastomosing +  and simple +
conspicuous +
on rock +  and terrestrial +