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Chinese brake, Chinese ladder brake, ladder brake

Bahama brake, Bahama ladder brake, plumy ladder brake

Stems

stout, short-creeping, densely scaly;

scales pale brown.

slender, short-creeping, sparsely scaly;

scales dark brown to black.

Leaves

clustered, 1–10 dm.

clustered, to ca. 1 m.

Petiole

green to pale brown, 1–30 cm, densely scaly;

scales dense proximally, extending to and along rachis.

green or straw-colored to purple-black proximally or medium brown with age, 10–25(–45) cm, glabrous or sparingly scaly at base, glabrous at maturity.

Blade

oblanceolate, 1-pinnate, (15–)25–50(–80) × (6–)13–25 cm;

rachis not winged.

lanceolate, broadly linear or oblanceolate, 1-pinnate, 25–50(–60) × 3–16 cm;

rachis not winged.

Pinnae

numerous, separated proximally, closely spaced to barely overlapping distally, not remaining green through winter, not decurrent on rachis, not articulate to rachis, linear-lanceolate to linear-attenuate, simple, 2–18 cm × 4–9 mm;

base asymmetrically cordate to widened or truncate;

margins serrulate, prominently so near apex;

apex acuminate, attenuate, or acute;

scales of rachis grading into uniseriate hairs on abaxial costae, or hairs absent on abaxial costae;

proximal pinnae not divided or lobed.

often numerous, well separated, mostly green over winter, not decurrent on rachis, articulate to rachis, narrowly linear, simple, 1.5–9 cm × 1.5–5 mm;

base rounded or auriculate and widened but not cordate;

margins obscurely dentate, often appearing entire;

apex short-acute to obtuse;

pinnae glabrous or rarely with a few scattered hairs abaxially on costa.

Veins

free, forked.

free, forked.

Sori

narrow, blade tissue exposed abaxially.

broad, little blade tissue exposed abaxially.

2n

= 116.

= 116.

Pteris vittata

Pteris bahamensis

Habitat Roadsides and other disturbed habitats, coastal plain In crevices and pockets on oölitic limestone in rocky pinelands and infrequently on the edges of hammocks
Elevation 0–50 m (0–200 ft) 0–50 m (0–200 ft)
Distribution
from FNA
AL; CA; DC; FL; GA; LA; MS; SC; South America; West Indies; native to Asia [Introduced in North America]
[WildflowerSearch map]
[BONAP county map]
from FNA
FL; West Indies in the Bahamas
[BONAP county map]
Discussion

Pteris vittata has escaped from cultivation. It is found on almost any calcareous substrate, such as old masonry, sidewalks, building crevices, and nearly every habitat in southern Florida with exposed limestone, notably pinelands. It is scattered throughout Florida and is sporadic, becoming less frequent to rare northward in the coastal plain.

Pteris vittata varies exceedingly in size, density of scales on the rachis, presence or absence of hairs on the abaxial costae, and overall color and aspect of the leaf. As a result, it may occasionally bear a resemblance to forms of P. × delchampsii W. H. Wagner & Nauman, the hybrid between P. bahamensis and P. vittata.

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

A form with dissected, deeply or completely 1–2-pinnate pinnae occurs throughout the range of Pteris bahamensis and is known in the flora from southern Florida.

Pteris bahamensis is often treated as a variety of P. longifolia Linnaeus, and some transition toward that species is evident. The primary differences are in the degree of rachis pubescence (denser in P. longifolia) and in pinna base shape (typically cordate in P. longifolia). The presence of transitional specimens and the quantitative nature of the differences suggest the taxa may be conspecific. Little is known, however, about the ranges and patterns of variation in both taxa. Pteris bahamensis is diploid and P. longifolia appears to be tetraploid. The two taxa are closely related, and further cytological and morphometric analyses will be needed before their relationships can be stated with confidence. Pteris bahamensis is maintained here at the species rank to emphasize the differences between the two taxa, though they are perhaps better treated as subspecies. Specimens identified as P. longifolia from the flora are P. bahamensis.

Pteris × delchampsii W. H. Wagner & Nauman is intermediate between Pteris bahamensis and P. vittata. Hybrid plants resemble a narrow, skeletonized form of P. vittata but have darker, shorter, and fewer stem scales, the petioles and rachises are less densely scaly, and pinnae are stiffer, farther apart, slender, and less ascending, with the margins less sharply dentate. The spores are largely misshapen. The chromosome number is 2n = 116, with irregular pairing.

Pteris × delchampsii is terrestrial or on rock in disturbed calcareous habitats on limestone walls and ledges in Broward, Dade, and Monroe counties, Florida; it is also thought to occur in Collier County, Florida. Outside the flora it occurs in the West Indies in the Bahamas.

Plants of Pteris × delchampsii most often resemble one of the parent species, and this may confound identification. Hybrids can be distinguished by the high percentage of misshapen, collapsed, or empty spores and abortive sporangia.

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

Source FNA vol. 2. FNA vol. 2.
Parent taxa Pteridaceae > Pteris Pteridaceae > Pteris
Sibling taxa
P. bahamensis, P. cretica, P. multifida, P. tripartita
P. cretica, P. multifida, P. tripartita, P. vittata
Synonyms Pycnodoria vittata P. diversifolia var. bahamensis, P. longifolia var. bahamensis, Pycnodoria bahamensis, Pycnodoria pinetorum
Name authority Linnaeus: Sp. Pl. 2: 1074. 1753, not Schkuhr. (1809) (J. Agardh) Fée: Mém. Foug. 5: 125. (1852)
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