Rhizome: erect, short, branching, scales clathrate, dark brown to black, to 4 mm. Frond: 18 cm high by 1.2 cm wide, evergreen, somewhat dimorphic, fertile fronds stiff, erect, sterile prostrate, only to 10 cm, blade/stipe ratio: 1:1 to 6:1. Stipe: reddish brown at base, green distally, lustrous, dark reddish brown to black, narrowly triangular scales grading into glandular hairs, vascular bundles: 2 C-shaped, back to back, uniting to 1 upwards in an X-shape. Blade: 1-pinnate, linear, widest above the middle, tapering to either end, thin, pale green, glabrous or with sparse minute hairs. Pinnae: 6 to 21 pair, rhombic or ovate, apex rounded to acute, sometimes toothed, subopposite; costae indistinct; margins crenate or entire; veins free, forked. Sori: linear, 1.5 mm, 1-2 pairs per pinna, paired across the midrib, indusium: white or translucent, thin, entire, often deciduous, on one side of the sorus, sporangia: brown, maturity: midsummer to late fall. Dimensionality: pinnae tilted forward in lower part of blade.