General:
Delicate aquatic ferns floating on water surface; plants usually 2-6 cm long, pinnately branched from a central axis, dichotomously branched only at the periphery; fronds usually densely overlapping like shingles.
Leaves:
The upper lobes 0.8-1 mm long.Sporocarps Borne on floating lobes; hooked hairs without cross-walls or rarely with 1 or 2 cross-walls; megaspores net-veined with raised hexagons at the base.
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia