Amer. Fern J. 58: 141. 1968.
Leaves monomorphic or weakly subdimorphic, 10–30 cm. Blade 4-pinnate, 3–12 cm, nearly as wide as long, thin to thick. Ultimate segments narrowly lanceolate to deltate, 2–6 mm; midrib obscure or evident abaxially. Sori of mature blades ± discrete to usually subcontinuous, 3–7 (–9) per segment; indusia semicircular to usually elongate and connecting several adjacent sori, margins with 6–10 irregular and prominent teeth and/or lobes. 2n = 120.
100–1400 m, Calif.
Aspidotis carlotta-halliae is a fertile allotetraploid species derived from hybridization between A. californica and A. densa. Occasional sterile backcrosses are found.
Generally on serpentine slopes, in crevices, and on rock outcrops