Potamogeton foliosus subsp. fibrillosus (Fernald) R.R.Haynes & Hellq.

Stems: glands common, to 0.5 mm diam. Leaves: stipules brown or rarely white, fibrous, shredding at tip, veins in age remaining as fibers. Inflorescences: spikes interrupted. Fruits pale-green, 1.4--1.7 ´ 1.1--1.2 mm; keel less than or equal to 0.2 mm high; beak less than or equal to 0.2 mm. Chromosome number unknownnot available.