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1 Leaves strongly bicolored (pale green toward the base of each of the 4 leaflets, darker green toward the tip); aquatic forms with a swollen air bladder just below the leaf
....3 Distal tooth 0.3-0.8 mm long; sporocarps 3.5-5.0 mm long; sporocarps 1 or 2(-4) per fertile frond, attached to stipe up to 5 mm above stipe base; common peduncle joining 2 peduncles to stipe, if present then only 1 mm
....3 Distal tooth absent or < 0.2 mm long; sporocarps 4.5-6.0 mm long; sporocarps (1-) 2-5 (-7) per fertile frond, attached to stipe up to 25 mm above stipe base; common peduncle joining 2 or more peduncles to stipe 2-8 mm
......4 Distal tooth absent or a very low bump (< 0.2 mm long); leaf lower surface densely spreading pubescent
......4 Distal tooth 0.4-1.2 mm long, sharply acute to pointed, often hooked; leaf lower surface glabrate to sparsely appressed pubescent