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alpine cliff fern, alpine woodsia, northern cliff fern, woodsie alpine

New Mexican cliff fern, New Mexico cliff fern

Stems

compact, erect to ascending, with cluster of persistent petiole bases of ± equal length;

scales uniformly brown, lanceolate.

compact, erect to ascending, 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

2.5–20 × 0.5–2.5 cm.

4–30 × 1.5–6 cm.

Petiole

reddish brown or dark purple when mature, articulate above base at swollen node, 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

linear to narrowly lanceolate, usually pinnate-pinnatifid proximally, lacking glands, never viscid;

rachis with widely scattered hairs and scales.

linear to lanceolate, usually pinnate-pinnatifid proximally, glabrescent to sparsely glandular, never viscid;

glandular hairs with thin stalks and slightly expanded tips;

rachis with scattered glandular hairs and rare, hairlike scales.

Pinnae

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

largest pinnae with 1–3 pairs of pinnules;

abaxial surface with isolated hairs and linear scales, adaxial surface glabrous.

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

largest pinnae with 3–7 pairs of closely spaced pinnules;

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

Indusia

of narrow, hairlike segments, these uniseriate throughout, composed of cells many times longer than wide, usually surpassing mature sporangia.

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

Spores

averaging 46–53 µm.

averaging 44–52 µm. 2n = 152.

Pinnules

entire or broadly crenate;

margins nonlustrous, thin, with occasional isolated cilia, lacking translucent projections.

dentate, often shallowly lobed;

margins nonlustrous, thin, with occasional glands, lacking cilia, with 1–2-celled translucent projections on teeth.

Vein

tips often enlarged to form whitish hydathodes visible adaxially.

tips occasionally enlarged to form whitish hydathodes visible adaxially.

Woodsia alpina

Woodsia neomexicana

Phenology Sporulating summer–early fall. Sporulating summer–fall.
Habitat Crevices and ledges on cliffs (occasionally on rocky slopes), mostly slaty and calcareous rocks Cliffs and rocky slopes, usually on sandstone or igneous substrates
Elevation 0–1500 m (0–4900 ft) 300–3500 m (1000–11500 ft)
Distribution
from FNA
AK; ME; MI; MN; NH; NY; VT; BC; MB; NB; NF; NS; NT; ON; QC; SK; YT; Greenland; n Eurasia
[BONAP county map]
from FNA
AZ; CO; NM; OK; SD; TX
[WildflowerSearch map]
[BONAP county map]
Discussion

Isozyme studies confirm the longstanding hypothesis that Woodsia alpina is an allotetraploid derived from hybridization between W. glabella and W. ilvensis (see reticulogram). Considerable disagreement exists concerning the chromosome number of W. alpina, but 2n = 160 seems most likely, given the numbers reported for the two parental species. Hybrids between W. alpina and W. ilvensis have been reported from both Europe and North America. These morphologically intermediate triploids with malformed spores have been called W. × gracilis (Lawson) Butters.

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

Woodsia neomexicana traditionally has been identified as W. mexicana. Both taxa are tetraploid and may share one parent (M. D. Windham 1993); W. neomexicana is separated from typical W. mexicana by its completely filamentous indusial segments, reduced glandularity, and more northerly distribution. Isozyme data suggest that W. neomexicana is an allotetraploid hybrid between W. phillipsii and the diploid progenitor of W. oregana subsp. cathcartiana (M. D. Windham 1993). As with all allopolyploids, W. neomexicana can vary in the direction of either parent, and some plants (especially those resembling W. phillipsii) can be difficult to identify. All characters except those controlled directly by ploidy level show this tendency, and spore size remains the most dependable character for distinguishing W. phillipsii and W. neomexicana. This species hybridizes with W. oregana subsp. cathcartiana and W. phillipsii to produce sterile tetraploids and triploids, respectively.

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

Source FNA vol. 2. FNA vol. 2.
Parent taxa Dryopteridaceae > Woodsia Dryopteridaceae > Woodsia
Sibling taxa
W. cochisensis, W. glabella, W. ilvensis, W. neomexicana, W. obtusa, W. oregana, W. phillipsii, W. plummerae, W. scopulina
W. alpina, W. cochisensis, W. glabella, W. ilvensis, W. obtusa, W. oregana, W. phillipsii, W. plummerae, W. scopulina
Synonyms Acrostichum alpinum, W. alpina var. bellii, W. bellii, W. hyperborea, W. ilvensis var. alpina
Name authority (Bolton) Gray: Nat. Arr. Brit. Pl. 2: 17. (1822) Windham: Contr. Univ. Michigan Herb. 19: 52. (1993)
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