Wolffiella denticulata (Hegelm.) Hegelm.

Fronds. Vegetative fronds submerged, the basal part near the surface of the water and the tip bent downwards, coher 2-7 together (often grouped star-like); narrow, ribbon-shaped, truncated or rounded at the tip, with 2-4 short triangular teeth, 2-7 mm long, 0.3-0.8 mm wide, 6-15 times as long as wide, with 0-5 stomata (along the lateral margins of the base); air spaces distinct, the area containing air spaces much longer than wide, spreading throughout most of the frond; angle of the pouch 25-40 ; tract of elongated cells running along the edge of the lower wall of the pouch; the point of attachment of the daughter frond after separation very prominent. Reproductive fronds wider and shorter than the vegetative ones, float on the surface of the water, coher together with a submerged vegetative frond. INFLORESCENCE: Flowers and fruits. Plants rarely flowering and fruiting. Flowering fronds much shorter and wider than the vegetative ones, coher together with a vegetative frond; 1 flower per frond; ripe fruits not known.