Thelypteris dentata |
Thelypteris quelpaertensis |
|
---|---|---|
downy maiden fern, downy shield fern, tapering tri-vein fern |
mountain fern, mountain marsh fern, queen's-veil maiden fern |
|
Stems | short-creeping, 4–6 mm diam. |
short-creeping to suberect, 5–10 mm diam. |
Leaves | often somewhat dimorphic, evergreen, often closely placed, 50–150 cm, fertile leaves with longer petioles and more contracted pinnae. |
monomorphic, dying back in winter, crowded, (15–)25–100 cm. |
Petiole | often purplish brown, 15–50 cm × 3–6 mm, at base with brown, linear-lanceolate, hairy scales. |
straw-colored to tan above base, 3–20 cm × 2–5 mm, scales on petioles and rachises tan to straw-colored, persistent, ovate to lanceolate. |
Blade | (25–)40–100 cm, 1–4(–6) proximal pairs of pinnae reduced, blade gradually tapered to pinnatifid apex. |
elliptic, 25–80 cm, 5–10 pairs of proximal pinnae gradually smaller toward base, lowest pinnae ca. 1 cm, blade tapering gradually to pinnatifid apex. |
Pinnae | 7–17 × 1–3 cm, incised 1/2–3/4 of width; segments rounded at apex, basal acroscopic segment of proximal pinnae often auriculate; proximal pair of veins from adjacent segments united at obtuse angle below sinus with excurrent vein 2–4 mm. |
deeply pinnatifid to ca. 1 mm or less from costa, 3–12 × 1–2 cm; segments linear to oblong, somewhat oblique and often somewhat curved, entire or crenulate, basal segments of proximal pinnae more often crenulate; proximal pair of veins from adjacent segments meeting margin above sinus. |
Sori | round, medial to supramedial; indusia tan, pubescent, hairs 0.1–0.3 mm; sporangial stalks with orangish, stalked glands. |
round, submarginal; indusia tan, glabrous; sporangia glabrous. |
Indument | abaxially of uniformly short hairs 0.1–0.2 mm on costae, veins, and blade tissue; veins adaxially with stouter hairs, also with hairs 0.1–0.2 mm on blade tissue. |
abaxially of tan to whitish linear scales along costae, hairs lacking or sparse along costae, blade tissue lacking glands or sparsely glandular. |
2n | = 144. |
= 68. |
Thelypteris dentata |
Thelypteris quelpaertensis |
|
Habitat | Damp woods | Terrestrial in open, rocky woods and subalpine meadows in acid soils |
Elevation | 0–100 m (0–300 ft) | 30–1300 m (100–4300 ft) |
Distribution |
AL; FL; GA; KY; LA; s Mexico; West Indies in the Antilles; South America to n Argentina; native to tropical and subtropical Asia; Africa [Introduced in North America] |
AK; WA; BC; Nfld; e Asia
|
Discussion | Thelypteris dentata probably does not persist northward in areas (such as Kentucky) where winters are sometimes severe (R. Cranfill 1980). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Although the name Thelypteris limbosperma (Allioni) H. P. Fuchs, type from Europe, has usually been applied to plants in the flora, specimens from western North America match more closely those from eastern Asia; therefore, a name based on a Korean type is used here. The single collection from the coast of Newfoundland (reported by A. Bouchard and S. G. Hay 1976) is remarkably disjunct but matches collections from western North America rather than those of the European species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 2. | FNA vol. 2. |
Parent taxa | Thelypteridaceae > Thelypteris > subg. Cyclosorus | Thelypteridaceae > Thelypteris > subg. Lastrea |
Sibling taxa | ||
Synonyms | Polypodium dentatum, Christella dentata, Cyclosorus dentatus, Dryopteris dentata, Dryopteris mollis, T. reducta | Dryopteris quelpaertensis, Oreopteris quelpaertensis |
Name authority | (Forsskål) E. P. St. John: Amer. Fern J. 26: 44. (1936) | (H. Christ) Ching: Bull. Fan Mem. Inst. Biol. 6: 328. (1936) |
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