Thelypteris tetragona

(Swartz) Small

Ferns S. E. States 256. 1938.

Common names: Free-tip star-hair fern
Basionym: Polypodium tetragonum Swartz Prodr., 132. 1788
Synonyms: Dryopteris tetragona (Swartz) Urban Goniopteris tetragona (Swartz) C. Presl
Treatment appears in FNA Volume 2.

Stems short-creeping, 3–5 mm diam. Leaves somewhat dimorphic, evergreen, somewhat spaced, fertile leaves long-petioled, more erect, and with more contracted pinnae, to ca. 1.1 m. Petiole straw-colored, to 60 cm × 2–5 mm, at base sparsely set with brown, lanceolate, stellate-hairy scales. Blade 30–45 (–55) × 15–25 cm, broadest at base, with apical pinna similar to lateral pinnae. Pinnae 6–8 (–12) pairs, 7–15 (–18) × 2–3 cm (fertile 1–2 cm), incised 1/2–3/4 of width; segments 3–5 mm wide, rounded at apex; veins 6–10 pairs, proximal pair from adjacent segments united at obtuse angle below sinus with excurrent vein ca. 0.5–1 mm to sinus. Indument abaxially of mostly needlelike hairs 0.1–0.3 mm on costae and veins, blade tissue glabrous on both sides. Sori round, medial to supramedial; indusia lacking; sporangia with numerous hairs 0.1 mm. 2n = 144.


Habitat: Damp woods
Elevation: 0–50 m

Distribution

V2 395-distribution-map.gif

Fla., Mexico, West Indies in the Antilles, Central America to Panama, n South America

Discussion

Selected References

None.

Lower Taxa

None.

No values specified."/2" is not declared as a valid unit of measurement for this property.

... more about "Thelypteris tetragona"
reduced +
Alan R. Smith +
(Swartz) Small +
Polypodium tetragonum +
45 cm450 mm <br />0.45 m <br /> (55 cm550 mm <br />0.55 m <br />) +
30 cm300 mm <br />0.3 m <br /> (45 cm450 mm <br />0.45 m <br />) +
1-pinnate +  and pinnate-pinnatifid +
Free-tip star-hair fern +
Fla. +, Mexico +, West Indies in the Antilles +, Central America to Panama +  and n South America +
0–50 m +
glandular +  and hairy +
not continuous +
Damp woods +
branched +  and simple +
transparent +
0.1 cm1 mm <br />0.001 m <br /> (?) +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
ephemeral +  and persistent +
round-reniform +
small +  and large +
long-petioled +
evergreen +
0 cm0 mm <br />0 m <br /> (110 cm1,100 mm <br />1.1 m <br />) +
reticulate +  and echinate +
straw-colored +
0 cm0 mm <br />0 m <br /> (60 cm600 mm <br />0.6 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
short-stalked +  and sessile +
15 cm150 mm <br />0.15 m <br /> (18 cm180 mm <br />0.18 m <br />) +
7 cm70 mm <br />0.07 m <br /> (15 cm150 mm <br />0.15 m <br />) +
6 (?) +  and 8 (?) +
not +  and reduced +
Ferns S. E. States +
stellate-hairy +
lanceolate +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
hairy +  and glabrous +
0.15 cm1.5 mm <br />0.0015 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
long-creeping;ascending +
Dryopteris tetragona +  and Goniopteris tetragona +
Thelypteris tetragona +
Thelypteris subg. Goniopteris +
species +
crescent--shaped +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
furcate +  and stellate +
on rock +  and terrestrial +