Potamogeton tennesseensis

Fernald

Rhodora 38: 167, plate 412. 1936.

Common names: Tennessee pondweed
EndemicConservation concern
Treatment appears in FNA Volume 22.

Rhizomes present. Cauline stems terete, without spots, 10–35 cm; glands absent. Turions absent. Leaves both submersed and floating or floating absent, ± spirally arranged. Submersed leaves sessile, lax; stipules persistent, inconspicuous, convolute, adnate to blade for ¼ or less stipule length, light brown to dark green, ligulate, 0.5–1.5 cm, not fibrous, not shredding at tip, apex acute; blade red-brown to dark green, linear-filiform, not arcuate, 2.5–10.5 cm × 0.2–1(–2) mm, base slightly tapering, not clasping, without basal lobes, margins entire, not crispate, apex not hoodlike, long tapering, lacunae abundant, broad, filling area between margin and midvein; veins 1–3. Floating leaves petiolate; petioles continuous in color to apex, 2.5–6 cm; blade greenish brown adaxially, lance-oblong, 2–4(–5.5) cm × 5–13 mm, base acute, apex acute; veins 9–23. Inflorescences unbranched, emersed; peduncle not dimorphic, axillary, ascending, cylindric, 3–8 cm; spikes not dimorphic, cylindric, 10–22 mm. Fruits sessile, greenish brown, quadrate-orbicular, slightly compressed, abaxially keeled, laterally ridged, 2.5–3 × 2–2.5 mm; lateral ridges without points; beak present, erect, 0.5 mm; sides without basal tubercles; embryo with less than 1 full spiral.


Phenology: Flowering mid spring–fall.
Habitat: Slow- to fast-moving streams and rivers
Elevation: 200–1000 m

Distribution

V22 521-distribution-map.jpg

Ky., Md., N.C., Ohio, Pa., Tenn., Va., W.Va.

Discussion

No specimens have been seen from Maryland although the species is to be expected there.

Of conservation concern.

Selected References

None.

Lower Taxa

None.
... more about "Potamogeton tennesseensis"
Robert R. Haynes +  and C. Barre Hellquist +
Fernald +
Tennessee pondweed +
Ky. +, Md. +, N.C. +, Ohio +, Pa. +, Tenn. +, Va. +  and W.Va. +
200–1000 m +
Slow- to fast-moving streams and rivers +
Flowering mid spring–fall. +
Endemic +  and Conservation concern +
Potamogeton tennesseensis +
Potamogeton +
species +