Flora of North America species comparison

compact, erect to ascending, with cluster of persistent petiole bases of ± equal length;

scales uniformly brown, lanceolate.

compact, erect to ascending, with cluster of persistent petiole bases of ± equal length;

scales uniformly brown, lanceolate.

3.5–15 × 0.5–1.2 cm.

2.5–20 × 0.5–2.5 cm.

green or straw-colored throughout, articulate above base at swollen node, somewhat pliable and resistant to shattering.

reddish brown or dark purple when mature, articulate above base at swollen node, relatively brittle and easily shattered.

linear to linear-lanceolate, pinnate-pinnatifid proximally, glabrous or with occasional sessile glands, never viscid;

rachis glabrous.

linear to narrowly lanceolate, usually pinnate-pinnatifid proximally, lacking glands, never viscid;

rachis with widely scattered hairs and scales.

ovate-lanceolate to deltate, longer than wide, abruptly tapered to a rounded or broadly acute apex;

largest pinnae with 1–3 pairs of pinnules;

abaxial surface with isolated hairs and linear scales, adaxial surface glabrous.

of narrow hairlike segments, these uniseriate throughout, composed of cells many times longer than wide, usually surpassing mature sporangia.

of narrow, hairlike segments, these uniseriate throughout, composed of cells many times longer than wide, usually surpassing mature sporangia.

averaging 39–45 µm. 2n = 78.

averaging 46–53 µm.

pinnae fan-shaped, wider than long;

distal pinnae ovate-lanceolate, longer than wide, abruptly tapered to a rounded or broadly acute apex;

largest pinnae with 1–3 pairs of pinnules, abaxial and adaxial surfaces glabrous.

entire or broadly crenate;

margins nonlustrous, thin, lacking cilia or translucent projections.

entire or broadly crenate;

margins nonlustrous, thin, with occasional isolated cilia, lacking translucent projections.

tips slightly (if at all) enlarged, barely visible adaxially.

tips often enlarged to form whitish hydathodes visible adaxially.