Woodsia ilvensis
Woodsia plummerae
oblong woodsia, rusty cliff fern, rusty woodsia, woodsie de l'île d'elbe
Plummer's cliff fern, Plummer's woodsia
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.
reddish brown to dark purple when mature, not articulate above base, somewhat pliable and resistant to shattering.
narrowly lanceolate, usually 2-pinnate proximally, lacking glands, never viscid;
rachis usually with abundant hairs and scales.
lanceolate to ovate, usually 2-pinnate proximally, densely glandular, often somewhat viscid;
most glandular hairs with thick stalks and distinctly bulbous tips;
rachis with abundant glandular hairs and a few narrow 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 5–11 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 for most of length, often divided and uniseriate distally, composed of ± isodiametric cells, often surpassing mature sporangia.
averaging 39–46 µm. 2n = 82.
averaging 44–50 µm. 2n = 152.
entire or crenate, rarely shallowly lobed;
margins nonlustrous, thin, ciliate with multicellular hairs, lacking translucent projections.
dentate, often shallowly lobed;
margins nonlustrous, thin, densely glandular, lacking cilia but with occasional 1–2-celled translucent projections.
tips frequently enlarged to form whitish hydathodes visible adaxially.
tips slightly (if at all) enlarged, barely visible adaxially.
Woodsia ilvensis
Woodsia plummerae
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.)
The origin and phylogenetic affinities of the tetraploid Woodsia plummerae have not been established with certainty. The hypothesis that it arose as a hybrid between the Mexican species W. mollis (Kaulfuss) J. Smith and W. mexicana Fée (D. F. M. Brown 1964; D. B. Lellinger 1985) seems untenable in light of recent chromosome studies indicating that the latter species is also tetraploid (M. D. Windham 1993). On the basis of sporophyte morphology and spore ornamentation, W. plummerae appears most closely related to the W. mexicana complex and W. oregana. In fact, W. oregana can be difficult to separate from W. plummerae in western New Mexico and northern Arizona. Intermediate plants occurring in this region may represent stable allotetraploids resulting from hybridization between the diploid progenitors of W. plummerae and W. oregana subsp. cathcartiana. Considering the available evidence, populations of W. plummerae in the United States probably originated through autopolyploidy from a recently discovered, but as yet unnamed, Mexican diploid of similar morphology. Woodsia plummerae occasionally hybridizes with W. phillipsii to produce sterile, morphologically intermediate triploids.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
BC
Go Botany
IL Wildflowers
MD Biodiversity
MI Flora
MN Wildflowers
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
CA
