Myriophyllum votschii Schindl.

Dioecious perennial herb; stems usually prostrate, rarely erect, forming often patches or tight cushions to 7 cm high, branching freely, rooting at nodes, forming clumps to 10 cm diam. Lvs monomorphic, opposite, entire, obovoid or nearly so, 1.8-3.5 × (0.5)-0.7-1.1 mm, ± flat or slightly concave on upper surface, convex below, spreading or slightly upward-curving. Submerged lvs present. Fls in the axils of upper lvs; fertile lvs similar to lower lvs. Bracteoles linear, 0.5-0.7 × 0.1-0.2 mm. ♂ fls sessile, usually in axils of the uppermost pair of lvs only; sepals 0; petals 4, with reddish spot at tip, rarely completely dark red, hooded, 1.5-1.8 × 0.7-1 mm. ♀ fls sessile, in axils of upper 4-8 pairs of lvs; sepals, petals and stamens 0. Frs 0.9-1 × 1.1-1.4 mm diam., depressed-globular, smooth or weakly punctate on dorsal surface of mericarps.