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blunt-lobe woodsia, blunt-lobed cliff fern, bluntlobe cliff fern, woodsie à lobes arrondis

Phillips' cliff fern

Stems

compact to creeping, erect to horizontal, with few to many persistent petiole bases of unequal lengths;

scales often uniformly brown but at least some bicolored with dark central stripe and pale brown margins, narrowly lanceolate.

compact to short-creeping, erect to horizontal, with few to many persistent petiole bases of unequal lengths;

scales mostly uniformly brown but at least some bicolored with dark central stripe and pale brown margins, narrowly lanceolate.

Leaves

8–60 × 2.5–12 cm.

5–35 × 1.5–6 cm.

Petiole

light brown or straw-colored when mature, occasionally darker at very base, not articulate above base, relatively brittle and easily shattered.

light brown or straw-colored when mature, occasionally darker at very base, not articulate above base, relatively brittle and easily shattered.

Blade

lanceolate to ovate, 2-pinnate to 2-pinnate-pinnatifid proximally, moderately glandular, rarely somewhat viscid;

many glandular hairs with thick stalks and distinctly bulbous tips;

rachis with glandular hairs and scattered, often hairlike scales.

lanceolate, usually 2-pinnate proximally, sparsely to moderately glandular, never viscid;

glandular hairs with thin stalks and slightly expanded tips;

rachis with scattered glandular hairs and hairlike scales.

Pinnae

ovate-deltate to elliptic, longer than wide, abruptly tapered to a rounded or broadly acute apex, occasionally attenuate;

largest pinnae with 5–14 pairs of pinnules;

abaxial and adaxial surfaces glandular, lacking nonglandular hairs or scales.

elongate-deltate to elliptic, longer than wide, often attenuate to a narrowly acute apex;

largest pinnae with 7–18 pairs of widely spaced pinnules;

abaxial and adaxial surfaces somewhat glandular, lacking nonglandular hairs or scales.

Indusia

of relatively broad, nonfilamentous segments, these multiseriate throughout, composed of ± isodiametric cells, entire or glandular along distal edge, concealed by or slightly surpassing mature sporangia.

of narrow, filamentous segments, these uniseriate for most of length, composed of ± isodiametric cells, often greatly surpassing mature sporangia.

Spores

averaging 35–47 µm.

averaging 37–44 µm. 2n = 76.

Pinnules

dentate, sometimes deeply lobed;

margins nonlustrous, thin, with occasional glands, lacking cilia or translucent projections.

dentate, often shallowly lobed;

margins often lustrous adaxially, somewhat thickened, with occasional glands, appearing ciliate due to presence of multicellular translucent projections on teeth that are often prolonged to form twisted filaments.

Vein

tips usually enlarged to form whitish hydathodes visible adaxially.

tips usually enlarged to form whitish hydathodes visible adaxially.

Woodsia obtusa

Woodsia phillipsii

Phenology Sporulating summer–fall.
Habitat Cliffs and rocky slopes, usually on granitic or volcanic substrates
Elevation 1600–3200 m (5200–10500 ft)
Distribution
from FNA
AL; AR; CT; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; VT; WI; WV; ON; QC; only in the flora
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from FNA
AZ; NM; TX; n Mexico
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[BONAP county map]
Discussion

Woodsia obtusa comprises two cytotypes that are treated here as subspecies because they show subtle morphologic and ecological distinctions and tend to have different distributions. Tetraploid populations (subsp. obtusa) are found throughout the eastern flora, commonly occurring on limestone. The diploid (subsp. occidentalis) is found near the western edge of the species range, usually on sandstone and granitic substrates. Isozyme studies suggest that subsp. obtusa may have been derived from subsp. occidentalis through autopolyploidy (M. D. Windham 1993). The westernmost collections of Woodsia obtusa (all subsp. occidentalis) come from the Wichita Mountains of Oklahoma and the Edwards Plateau of Texas. Reports of this species from the trans-Pecos region of western Texas are apparently based on misidentifications.

Subspecies 2.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Woodsia phillipsii traditionally has been identified as W. mexicana. It differs from typical W. mexicana, however, in having completely filamentous indusial segments, multicellular (often filamentous) translucent projections on the pinnule margins, a greater number of pinnules per pinna, and a diploid chromosome number. Woodsia phillipsii is the only diploid species currently recognized in the W. mexicana complex, and it was probably involved in the hybrid origins of both W. mexicana and W. neomexicana. Some individuals of the latter species are difficult to distinguish from W. phillipsii (see comments under W. neomexicana), and the two taxa occasionally hybridize to produce sterile triploids of intermediate morphology. Woodsia phillipsii is also known to hybridize with W. plummerae (see comments under that species) and W. cochisensis.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Spores averaging 42-47 µm; proximal pinnules of lower pinnae usually shallowly lobed or merely dentate; blades coarsely cut and evidently 2-pinnate; stems compact to short-creeping, individual branches usually 5-10 mm diam.
subsp. obtusa
1. Spores averaging 35-42 µm; proximal pinnules of lower pinnae usually deeply lobed or pinnatifid; blades finely cut, 2-pinnate-pinnatifid; stems short- to long-creeping, individual branches 3-5 mm diam.
subsp. occidentalis
Source FNA vol. 2. FNA vol. 2.
Parent taxa Dryopteridaceae > Woodsia Dryopteridaceae > Woodsia
Sibling taxa
W. alpina, W. cochisensis, W. glabella, W. ilvensis, W. neomexicana, W. oregana, W. phillipsii, W. plummerae, W. scopulina
W. alpina, W. cochisensis, W. glabella, W. ilvensis, W. neomexicana, W. obtusa, W. oregana, W. plummerae, W. scopulina
Subordinate taxa
W. obtusa subsp. obtusa, W. obtusa subsp. occidentalis
Synonyms Aspidium obtusum, W. perriniana
Name authority (Swartz) Torrey: New York State, Rep. Geol. Surv. 195. (1840) Windham: Contr. Univ. Michigan Herb. 19: 50. (1993)
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