Woodsia ilvensis
Woodsia cochisensis
oblong woodsia, rusty cliff fern, rusty woodsia, woodsie de l'île d'elbe
Cochise cliff fern
compact, erect to ascending, with abundant persistent petiole bases of ± equal length;
scales uniformly brown, lanceolate.
compact, erect to ascending, with a few 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.
4.5–25 × 1.2–3.5 cm.
5–25 × 1.5–6 cm.
usually brown or dark purple when mature, articulate above base at swollen node, relatively brittle and easily shattered.
light brown or straw-colored throughout when mature, occasionally darker at very base, not articulate above base, relatively brittle and easily shattered.
narrowly lanceolate, usually 2-pinnate proximally, lacking glands, never viscid;
rachis usually with abundant hairs and scales.
narrowly lanceolate to ovate, pinnate-pinnatifid to 2-pinnate proximally, sparsely to moderately glandular, never viscid;
glandular hairs with thin stalks and slightly expanded tips;
rachis with glandular hairs and occasional hairlike scales.
ovate-lanceolate to deltate, longer than wide, abruptly tapered to a rounded or broadly acute apex;
largest pinnae with 4–9 pairs of pinnules;
abaxial surface with mixture of hairs and linear-lanceolate scales, adaxial surface with multicellular hairs concentrated along midrib.
ovate-deltate to elliptic, longer than wide, abruptly tapered to a rounded or broadly acute apex, occasionally attenuate;
largest pinnae with 4–9 pairs of pinnules;
abaxial and adaxial surfaces glandular, lacking nonglandular hairs or scales.
of narrow, hairlike segments, these uniseriate throughout, composed of cells many times longer than wide, usually surpassing mature sporangia.
of relatively broad segments;
segments multiseriate most of length, usually divided and uniseriate distally, composed of ± isodiametric cells, often surpassing mature sporangia.
averaging 39–46 µm. 2n = 82.
averaging 43–49 µm. 2n = 152.
entire or crenate, rarely shallowly lobed;
margins nonlustrous, thin, ciliate with multicellular hairs, lacking translucent projections.
dentate, often shallowly lobed;
margins lustrous adaxially, usually thickened, lacking cilia but sparsely glandular, with occasional 1–2-celled translucent projections.
tips frequently enlarged to form whitish hydathodes visible adaxially.
tips enlarged to form whitish hydathodes visible adaxially.
Woodsia ilvensis
Woodsia cochisensis
Although generally separable by the characters given in the key, shade forms of Woodsia ilvensis with a reduced number of scales and hairs are occasionally misidentified as W. alpina. The morphologic distinctions between these species are further blurred by natural hybridization, which produces the intermediate triploid known as W. × gracilis. Some of the best characters for distinguishing these taxa are spore size and morphology. Spores average less than 46 µm in W. ilvensis, more than 46 µm in W. alpina, and are malformed and abortive in W. × gracilis. Woodsia ilvensis also hybridizes with W. oregana subsp. cathcartiana to form the sterile triploid W. × abbeae (F. S. Wagner 1987).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Woodsia cochisensis traditionally has been identified as W. plummerae or (rarely) W. mexicana Fée. It is readily separated from W. plummerae by the characteristics given in the key, and from North American members of the mexicana group (W. phillipsii and W. neomexicana) by having indusial segments that are broad and nonfilamentous at the base. Woodsia cochisensis is less glandular than typical W. mexicana from northeastern Mexico and is further distinguished from that species by the thickened, lustrous pinnule margins and well-developed hydathodes. Isozyme and chromosome studies suggest that W. cochisensis is an allotetraploid that may have originated through hybridization between W. phillipsii and an undescribed Mexican diploid (M. D. Windham 1993). It crosses with the former species to produce sterile triploids of intermediate morphology.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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