Distribution: Occurring chiefly east of the Cascades crest and in the Columbia River Gorge in Washington; British Columbia to California, east to the Great Plains and southeastern U.S.
Habitat: Ponds, vernal pools, and floodplains from low to middle elevations.
Conservation Status: Not of concern
Rhizomatous perennials forming clones, aquatic to amphibious; stems creeping on substrate surface or subterranean; roots emerging from nodes.
Leaves long-petiolate, petiole threadlike, 2-20 cm, slightly pubescent; blade palmately divided into 4 pinnae, pinnae obdeltate, 4-19 mm long and 4-16 mm broad, pubescent to glabrous.
Sporocarp stalks erect and not branched, attached at base of petiole or barely above it, not hooked at apex, 0.5-25 mm; sporocarps at right angle to stalk or slightly nodding, 3.6-7.6 mm long and 1.5-2 mm broad, elliptic to nearly round in lateral view, pubescent but becoming glabrous, scars from dropped trichomes commonly appearing as small purple or brown specks; sori 14-22.