Sonoran maiden fern

Stems creeping, 4--8 mm diam. Leaves monomorphic, evergreen, (0.5--)1--3 cm apart, 35--120(--165) cm. Petiole straw-colored, 15--60(--80) cm × 2--7 mm, at base sparsely set with brownish, lanceolate, hairy scales. Blade 20--55(--85) cm, broadest at or near base, gradually to somewhat abruptly tapered to pinnatifid apex. Pinnae 7--20(--26) × 1--2(--3) cm, incised 1/2--4/5 of width, proximal pinnae often narrowed toward base except for slightly enlarged acroscopic basal segment; segments oblique, somewhat curved; proximal 1--3 pairs of veins from adjacent segments connivent at sinus, or meeting margin just above sinus. Indument abaxially of often irregularly crimped hairs ca. 0.2--0.3 mm on costae, veins, and blade tissue, costae also with a few brownish scales less than 0.5 mm; blade tissue abaxially with scattered hairs ca. 0.2 mm. Sori round, medial to supramedial; indusia tan to brownish, usually densely hairy, hairs irregularly crimped, ca. 0.2 mm; sporangia glabrous.

In canyons, especially along streams and seepage areas, sometimes on calcareous substrates; 100--1300 m; Ariz., Calif.; w Mexico.