Thelypteris dentata

(Forsskål) E. P. St. John

Amer. Fern J. 26: 44. 1936.

Common names: Downy maiden fern downy shield fern tapering tri-vein fern
IntroducedIllustrated
Basionym: Polypodium dentatum Forsskål Fl. Aegypt.-Arab., 185. 1775
Synonyms: Christella dentata (Forsskål) Brownsey & Jermy Cyclosorus dentatus (Forsskål) Ching Dryopteris dentata (Forsskål) C. Christensen Dryopteris mollis (Swartz) Hieronymus Thelypteris reducta Small
Treatment appears in FNA Volume 2.
Revision as of 23:33, 29 July 2020 by imported>Volume Importer
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Stems short-creeping, 4–6 mm diam. Leaves often somewhat dimorphic, evergreen, often closely placed, 50–150 cm, fertile leaves with longer petioles and more contracted pinnae. Petiole often purplish brown, 15–50 cm × 3–6 mm, at base with brown, linear-lanceolate, hairy scales. Blade (25–) 40–100 cm, 1–4 (–6) proximal pairs of pinnae reduced, blade gradually tapered 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. 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. Sori round, medial to supramedial; indusia tan, pubescent, hairs 0.1–0.3 mm; sporangial stalks with orangish, stalked glands. 2n = 144.


Habitat: Damp woods
Elevation: 0–100 m

Distribution

V2 707-distribution-map.gif

Introduced; Ala., Fla., Ga., Ky., La., s Mexico, West Indies in the Antilles, South America to n Argentina, native to tropical and subtropical Asia, Africa

Discussion

Thelypteris dentata probably does not persist northward in areas (such as Kentucky) where winters are sometimes severe (R. Cranfill 1980).

Selected References

None.

Lower Taxa

None.

"/2" is not declared as a valid unit of measurement for this property.

... more about "Thelypteris dentata"
reduced +
Alan R. Smith +
(Forsskål) E. P. St. John +
Polypodium dentatum +
25 cm250 mm <br />0.25 m <br /> (40 cm400 mm <br />0.4 m <br />) +
gradually tapered +  and pinnatifid +
40 cm400 mm <br />0.4 m <br /> (100 cm1,000 mm <br />1 m <br />) +
Downy maiden fern +, downy shield fern +  and tapering tri-vein fern +
Ala. +, Fla. +, Ga. +, Ky. +, La. +, s Mexico +, West Indies in the Antilles +, South America to n Argentina +, native to tropical and subtropical Asia +  and Africa +
0–100 m +
glandular +  and hairy +
not continuous +
Damp woods +
branched +  and simple +
transparent +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
ephemeral +  and persistent +
round-reniform +
small +  and large +
monomorphic +
evergreen +
50 cm500 mm <br />0.5 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
reticulate +  and echinate +
purplish brown +
15 cm150 mm <br />0.15 m <br /> (50 cm500 mm <br />0.5 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
short-stalked +  and sessile +
7 cm70 mm <br />0.07 m <br /> (17 cm170 mm <br />0.17 m <br />) +
reduced +
not +  and reduced +
Amer. Fern J. +
linear-lanceolate +
Introduced +  and Illustrated +
hairy +  and glabrous +
0.15 cm1.5 mm <br />0.0015 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
long-creeping;ascending +
Christella dentata +, Cyclosorus dentatus +, Dryopteris dentata +, Dryopteris mollis +  and Thelypteris reducta +
Thelypteris dentata +
Thelypteris subg. Cyclosorus +
species +
crescent--shaped +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
on rock +  and terrestrial +