A)

Fronds deeply but simply pinnatifid, the lobes not secondarily lobed; sori round, often over 1.5 mm in diameter; indusium none.

B)

Fronds distinctly pinnate, at least toward the base, or if merely pinnatifid, then with the divisions further deeply lobed; sori either narrowly oblong, or if roundish, then smaller, with or without an indusium.