Leaves and stems:

Leaves (fronds) are evergreen, 2 to 8 inches long, up to 1 inch wide, lance-linear to oblong in outline, twice compound with 7 to 9 pairs of opposite leaflets (pinnae), the lowest pair usually further divided. New fronds are light green, older fronds dark green,

Pinnae segments are mostly round, the edges rolled under thus appearing bead-like. The upper surface is variously covered in coarse, tan hairs and may become hairless. The lower surface is densely long-hairy, the hairs initially white, turning tan. Veins are obscure.

Stems are dark brown to blackish, the lower stem (stipe) with a few brown scales and scattered, long hairs, the upper stem (rachis) covered in long, white hairs but no scales and becoming more sparsely hairy with maturity. Plants form a tight, compact clump and spread from short, creeping rhizomes.

Spores:

The sori (group of spores) develop on fertile fronds starting in early summer. They are linear-oblong in a continuous line around a pinnae segment edge. Spores ripen to black.

Notes:

Slender Lip Fern, formerly known as Cheilanthes feei, is found only in our southeast counties and is easily distinguished by the bead-like segments on the pinnae and long, coarse hairs. The only other fern in Minnesota of a similar size and degree of hairiness is Rusty Woodsia (Woodsia ilvensis), which also inhabits rock faces but has numerous, long scales all along the stem and on the lower surface of the pinnae, plus has round sori. The related Hairy Lip Fern (Cheilanthes lanosa) is not known to be present in Minnesota but is just across the river in southwest Wisconsin, is a rather larger plant (to 16 inches) and lacks the bead-like segments that are obvious on Slender Lip Fern.