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1 Leaves 1-pinnate; sori confluent, covering the lower surface of the fertile pinnae; [common, widespread, native] |
| 1 Leaves 1-pinnate-pinnatifid to 2-pinnate; sori distinct. |
| ..2 Leaf blade broadest near its midpoint, strongly narrowing towards base; pinnae outline oblong, with parallel margins for 1/2 to 3/4 of its length; [native, ec. PA northwards] |
| ..2 Leaf blade widest at base or 2-4 pinnae above the base; pinnae outline narrowly triangle, with margins angled towards the narrowly acuminate tip; [rare, alien] |
| ....3 Rachis densely pubescent with shaggy, orange to red pubescence |
| ....3 Rachis with scattered pubescence |