General:
Perennial, aquatic herb from fine, tufted roots; stems up to 100 cm long, sparingly branched.

Leaves:
All submersed, linear, the sides parallel, thin, green, 1-15 cm long, 0.3-3 cm wide, unstalked, usually with 3 veins, the tips pointed, the stipules 0.5-1 cm long, delicate, not fibrous, greenish or brownish, the margins fused, the veins obscure and faint, the basal glands at nodes well-developed.

Flowers:
Inflorescence spikelike, the spikes 0.5-1.5 cm long, with 2 to 5 whorls of flowers, the stalks thin; bases of the winter buds soft, smooth.

Fruits:
Achenes, almost rounded, 1.5-2.8 mm long, 1.6-2 mm wide, widest above the middle, the beaks short, stubby, the keels absent.

Notes:
Two subspecies, occasionally treated as separate species (e.g., Douglas et al 1994) can be distinguished in our area.

1. Stipules with fused margins; leaves without translucent bands along the midveins or with the bands up to 2-rows wide on each side of the midveins; marginal veins join the midveins about 2 mm from the leaf tips in a sharp angle....................ssp. pusillus

1. Stipules with overlapping margins; leaves with translucent bands up to 5-rows wide on each side of the midveins; marginal veins join the midveins about 0.5-1 mm from the leaf tips in a blunt (60 degree) angle....................ssp. tenuissimus (Mert. & Koch) Haynes & C.B. Hellquist

Source:  The Illustrated Flora of British Columbia

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

Synonyms and Alternate Names:
Potamogeton lateralis Morong p.p.
Potamogeton panormitanus Biv.
Potamogeton panormitanus var. major G. Fisch.
Potamogeton panormitanus var. minor Biv.
Potamogeton pusillus var. minor (Biv.) Fernald & B.G. Schub.
Potamogeton pusillus var. pusillus L.