The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

creeping cliff brake, intermediate cliffbrake

cliff-brake

Habit Plants usually on rock.
Stems

creeping, horizontal, slender, 2–4 mm diam.;

scales mostly bicolored, narrowly lanceolate, largest scales 0.3–0.8 mm wide, centers black, thick, margins brown, thin, irregularly dentate.

compact to long-creeping, ascending to horizontal, usually branched;

scales brown to tan or often bicolored with dark, central stripe and lighter margins, linear-subulate to lanceolate (rarely ovate), margins dentate, erose, or entire.

Leaves

monomorphic, widely scattered along stem, 12–50 cm;

croziers pubescent and bearing a few scales.

monomorphic to somewhat dimorphic, clustered to widely scattered, 2–100 cm.

Petiole

straw-colored, tan, or gray, not lustrous, rounded or slightly flattened adaxially, without prominent articulation lines.

brown, black, straw-colored, or gray, rounded, flattened or with single longitudinal groove adaxially, glabrous or pubescent, usually with a few scales at base, with single vascular bundle.

Blade

ovate to elongate-deltate, usually 2-pinnate proximally, 4–20 cm wide;

rachis tan throughout, straight to slightly flexuous, rounded or flattened adaxially, ± pubescent.

linear to ovate-deltate, 1–4-pinnate proximally, leathery or rarely somewhat herbaceous, abaxially glabrous, pubescent, or with hairlike scales scattered along costae, adaxially usually glabrous, dull, not striate;

rachis straight or flexuous.

Ultimate segments

ovate to elliptic, 5–15 mm, leathery, glabrous or usually puberulent abaxially;

margins recurved on fertile segments, usually covering less than 1/2 abaxial surface, borders whitish, nearly entire;

apex obtuse to slightly mucronate.

of blade usually stalked and free from costae, elliptic, lanceolate to linear, usually more than 4 mm wide;

base rounded, truncate, or cordate;

stalks often lustrous and dark colored;

segment margins reflexed to form confluent, poorly defined, false indusia extending entire length of segment.

Pinnae

perpendicular to rachis or slightly ascending, not decurrent on rachis, usually with 7–21 ultimate segments;

costae straight to slightly flexuous, 20–100 mm, longer than ultimate segments.

Veins

of ultimate segments obscure.

of ultimate segments free or rarely anastomosing, usually obscure, pinnately branched and divergent distally.

False indusia

greenish to whitish, narrow, clearly marginal, often concealing the sporangia.

Sporangia

short-stalked, containing 32 spores, not intermixed with farina-producing glands.

scattered along veins near segment margins, containing 32 or 64 spores, often intermixed with glands, farina-producing.

Spores

brown to tan (rarely yellow), tetrahedral-globose, rugose or cristate, lacking prominent equatorial ridge.

n

= 2n = 87, 116, apogamous.

x

= 29.

Pellaea intermedia

Pellaea

Phenology Sporulating summer–fall.
Habitat Rocky slopes and ledges, on a variety of substrates, including limestone and granite
Elevation 300–2400 m (1000–7900 ft)
Distribution
from FNA
AZ; NM; TX; n Mexico
[WildflowerSearch map]
[BONAP county map]
from USDA
Most in the Western Hemisphere; a small number in Asia; Africa; the Pacific Islands; and Australia
[BONAP county map]
Discussion

Plants of Pellaea intermedia in the flora are apogamous triploids and tetraploids; a sexual diploid cytotype has been found near Saltillo, Mexico (A. F. Tryon 1968). Given the high degree of morphologic similarity among the three cytotypes, the North American polyploids probably were derived from the Mexican diploid through autopolyploidy.

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

Pellaea in the broad sense is a diverse, poorly defined assemblage of xeric-adapted ferns (A. R. Smith 1981). Relationships among the North American, neotropical, and Eastern Hemisphere species are unclear, and it seems likely that the genus, as broadly construed by E. B. Copeland (1947) and R. M. Tryon and A. F. Tryon (1982), is polyphyletic. The species included here in Pellaea belong to a closely knit alliance that is usually recognized as a distinct section (sect. Pellaea). Although the inclusion of P. bridgesii in this group has been questioned (A. F. Tryon 1957), W. H. Wagner Jr. et al. (1983) have shown that the aberrant morphology of this species is simply an extreme expression of evolutionary trends commonly encountered in sect. Pellaea.

Among Western Hemisphere cheilanthoid ferns, species of Pellaea show clear morphologic, chromosomal, and biochemical affinities to Argyrochosma and members of the Cheilanthes alabamensis complex. In fact, the glabrous species of Argyrochosma (A. jonesii and A. microphylla) are commonly misidentified as Pellaea. These species are easily recognizable, however, because they have a combination of concolored stem scales and small ultimate segments (less than 4 mm wide).

Species ca. 40 (15 in the flora).

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

Key
1. Petioles and rachises straw-colored, tan, or gray, rarely lustrous; stem scales narrowly lanceolate to ovate, largest more than 0.3 mm wide.
→ 2
1. Petioles and rachises dark brown to black, usually lustrous; stem scales linear-subulate, less than 0.3 mm wide.
→ 5
2. Rachises and costae strongly flexuous; pinnae retrorse, projecting downward toward base of leaf.
P. ovata
2. Rachises and costae straight or slightly flexuous; pinnae perpendicular to rachis or ascending.
→ 3
3. Stems stout and compact, more than 5 mm diam.; stem scales uniformly orange-brown and thin; ultimate segments rotund-cordate to deltate-cordate.
P. cordifolia
3. Stems slender and long-creeping, less than 5 mm diam.; stem scales mostly bicolored, with black, thick center and brown, thin margins; ultimate segments elliptic to ovate-deltate, not deeply cordate.
→ 4
4. Ultimate segments leathery, veins obscure abaxially; croziers only slightly scaly; blades usually 2-pinnate at base.
P. intermedia
4. Ultimate segments somewhat herbaceous, veins visible abaxially; croziers densely scaly; blades usually 3-pinnate at base.
P. andromedifolia
5. Some stem scales bicolored, with dark central region and lighter, brown margin.
→ 6
5. Stem scales uniformly reddish brown or tan.
→ 11
6. Leaf blades linear, 1-pinnate throughout, pinnae entire; fertile ultimate segments with rounded apices; segment margins not recurved, not concealing sporangia.
P. bridgesii
6. Leaf blades linear-oblong to deltate, pinnate-pinnatifid to 3-pinnate, at least some pinnae lobed or divided; fertile ultimate segments with mucronate apices; segment margins recurved, usually concealing sporangia.
→ 7
7. Leaf blades deeply pinnate-pinnatifid at base, basal pinnae ternately lobed; petioles dark purple or black; sporangia not intermixed with farina-producing glands.
P. ternifolia
7. Leaf blades 2–3-pinnate at base, basal pinnae fully pinnate (occasionally appearing ternate but with terminal segment on short, dark stalk); petioles chestnut brown to dark reddish brown; sporangia intermixed with glands producing yellowish farina (sparse in Pellaea wrightiana).
→ 8
8. Pinna costae usually shorter than or equal to ultimate segments; largest pinnae divided into 3–11 segments; blades linear-oblong, usually less than 4.5 cm wide.
→ 9
8. Pinna costae much longer than ultimate segments; largest pinnae divided into 11 or more segments; blades ovate-deltate to lanceolate, usually more than 4.5 cm wide.
→ 10
9. Ultimate segments linear, with greenish, strongly recurved margins covering more than 1/2 abaxial surface; sporangia with short stalks; pinnae strongly ascending.
P. brachyptera
9. Ultimate segments narrowly oblong, with white-bordered, recurved margins usually covering less than 1/2 abaxial surface; sporangia with long stalks; pinnae perpendicular to rachis or slightly ascending.
P. wrightiana
10. Blades usually 2-pinnate proximally, pinnae perpendicular to rachis or slightly ascending; margins of ultimate segments with whitish borders; sporangia with long stalks.
P. truncata
10. Blades 3-pinnate proximally or, if 2-pinnate, pinnae strongly ascending; margins of ultimate segments with greenish borders; sporangia with short stalks.
P. mucronata
11. Ultimate segments glabrous abaxially or with isolated hairlike scales on a few segments or, if sparsely villous, then rachises nearly glabrous; pinnae or costae slightly decurrent on rachis; blades linear-oblong to lanceolate.
→ 12
11. Ultimate segments sparsely villous on abaxial costae; rachises variously pubescent; pinnae or costae not decurrent on rachis (obscurely so in Pellaea gastonyi); blades lanceolate, ovate, or deltate.
→ 13
12. Proximal pinnae usually bilobed and mitten-shaped; petioles with prominent articulation lines near base; rachises of mature leaves green in distal portion of blade; sporangia sessile or subsessile.
P. breweri
12. Proximal pinnae deeply divided into 3–7 lobes or segments (occasionally simple); petioles lacking articulation lines or, if present, then rachises of mature leaves brown to terminal pinna; some sporangia long-stalked.
P. glabella
13. Adaxial surface of rachis densely covered with short, curly, appressed hairs; largest ultimate segments (excluding terminal pinnae) usually more than 30 mm.
P. atropurpurea
13. Adaxial surface of rachis with sparse, long, divergent hairs; largest ultimate segments (excluding terminal pinnae) usually less than 30 mm.
→ 14
14. Proximal pinnae divided into 7–15 ultimate segments, segments shorter than longest pinna costae; fertile leaves usually more than 6 cm wide.
P. lyngholmii
14. Proximal pinnae divided into 3–7 ultimate segments, some segments longer than longest pinna costae; fertile leaves usually less than 6 cm wide.
P. gastonyi
Source FNA vol. 2. FNA vol. 2. Author: Michael D. Windham.
Parent taxa Pteridaceae > Pellaea Pteridaceae
Sibling taxa
P. andromedifolia, P. atropurpurea, P. brachyptera, P. breweri, P. bridgesii, P. cordifolia, P. gastonyi, P. glabella, P. lyngholmii, P. mucronata, P. ovata, P. ternifolia, P. truncata, P. wrightiana
Subordinate taxa
P. andromedifolia, P. atropurpurea, P. brachyptera, P. breweri, P. bridgesii, P. cordifolia, P. gastonyi, P. glabella, P. intermedia, P. lyngholmii, P. mucronata, P. ovata, P. ternifolia, P. truncata, P. wrightiana
Synonyms P. intermedia var. pubescens
Name authority Mettenius ex Kuhn: Linnaea 38: 84. (1869) Link: Fil. Spec. 59. (1841)
Web links