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bog fern, Massachusetts fern, thélyptère simulatrice

grid-scale maiden fern

Stems

long-creeping, 1.5–3 mm diam.

Leaves

monomorphic, dying back in winter, often 1 cm or more apart, fertile leaves often somewhat longer than sterile leaves, 25–80 cm.

Petiole

straw-colored above base, 12–45 cm × 1–3 mm, at base sparsely set with tan, ovate, glabrous scales.

Blade

lanceolate, 14–35 cm, proximal pinnae largest, or lowest pair slightly smaller, blade tapered gradually to pinnatifid apex.

Pinnae

deeply pinnatifid to ca. 1 mm from costa, 3–10 × 1–2 cm;

segments oblong, somewhat oblique, entire;

proximal pair of veins from adjacent segments meeting margin above sinus.

Sori

round, medial;

indusia tan, often glandular;

sporangia glabrous.

Indument

abaxially of sparsely set hairs 0.2–0.4 mm primarily on costae, also of yellowish short-stalked glands less than 0.1 mm, blade tissue with numerous reddish to orangish, resinous, shiny, sessile, hemispheric glands;

blades adaxially with scattered hairs on veins.

2n

= 128.

Thelypteris simulata

Thelypteris patens

Habitat Terrestrial in acid soils of shaded swamps and bogs, frequently associated with sphagnum
Elevation 0–100 m (0–300 ft)
Distribution
from FNA
CT; DE; MA; MD; ME; NH; NJ; NY; PA; RI; VA; VT; WI; WV; NB; NS; ON; QC
[WildflowerSearch map]
from FNA
FL; s Mexico; Central America; West Indies in the Antilles; South America to s Brazil and n Argentina
[BONAP county map]
Discussion

Varieties 3 (1 in the flora).

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

Source FNA vol. 2. FNA vol. 2.
Parent taxa Thelypteridaceae > Thelypteris > subg. Parathelypteris Thelypteridaceae > Thelypteris > subg. Cyclosorus
Sibling taxa
T. augescens, T. dentata, T. grandis, T. hispidula, T. interrupta, T. kunthii, T. nevadensis, T. noveboracensis, T. ovata, T. palustris, T. patens, T. pilosa, T. puberula, T. quelpaertensis, T. reptans, T. resinifera, T. reticulata, T. sclerophylla, T. serrata, T. tetragona
T. augescens, T. dentata, T. grandis, T. hispidula, T. interrupta, T. kunthii, T. nevadensis, T. noveboracensis, T. ovata, T. palustris, T. pilosa, T. puberula, T. quelpaertensis, T. reptans, T. resinifera, T. reticulata, T. sclerophylla, T. serrata, T. simulata, T. tetragona
Subordinate taxa
T. patens var. patens
Synonyms Aspidium simulatum, Parathelypteris simulata Polypodium patens, Christella patens, Cyclosorus arcuatus, Dryopteris patens
Name authority (Davenport) Nieuwland: Amer. Midl. Naturalist 1: 226. (1910) (Swartz) Small: Ferns S. E. States 243. (1938)
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