Potamogeton groenlandicus |
Potamogeton subsibiricus |
|
---|---|---|
Greenland pondweed |
potamot de l'ilenissei, Yenisei River pondweed, Yenissei River pondweed |
|
Cauline stems | terete, without spots, 20–50 cm; glands white, 0.1–0.7 mm diam. |
compressed-filiform, without spots, to 50 cm; glands white, 0.3–0.5 mm diam. |
Turions | terminal or axillary, common, 4.2–8.4 cm × 1.4–2.5 mm, soft; leaves ± 4-ranked; outer leaves 2 per side, base without corrugations, apex acute to apiculate; inner leaves unmodified. |
lateral, common, 3.5–9.5 cm × 2–5 mm, soft; leaves ± 2-ranked; outer leaves 3–4 per side, base not corrugate; inner leaves undifferentiated. |
Leaves | submersed, ± spirally arranged, sessile, delicate; stipules deliquescent to persistent, inconspicuous, convolute, free from blade, brown, not ligulate, 0.45–1.91 cm, not fibrous, not shredding at tip, apex obtuse; blade pale to deep green, linear, not arcuate, 2.6–8.8 cm × 0.7–1.7 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, acute to apiculate, lacunae absent or present, 0–3 rows each side of midrib; veins 7–11. |
submersed, ± spirally arranged, sessile, flaccid; stipules deliquescent, inconspicuous, convolute, free from blade, pale brown, not ligulate, 1–2 cm, not fibrous, not shredding, apex obtuse; blade dark green, linear, not arcuate, 3.5–9.5 cm × 1.5–2 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, rounded or nearly acute to mucronate, lacunae in 1–2 rows each side of midvein; veins 9–17. |
Inflorescences | unbranched, emersed; peduncles not dimorphic, terminal, erect, cylindric, 20 mm; spikes not dimorphic, cylindric, 5 mm. |
unbranched, emersed; peduncles not dimorphic, axillary, erect, cylindric, 1.7–3.5 cm; spikes not dimorphic, cylindric, 10–30 mm. |
Fruits | not laterally keeled, 2.6–2.7 × 2 mm; beak erect, 0.3 mm; sides without basal tubercles; embryo with 1 full coil. |
sessile, reddish brown, oblong-obovoid, compressed, abaxially ridged, not laterally keeled, 3–4 × 1.5–2 mm; beak nearly erect, 0.3–0.5 mm; sides without basal tubercles; embryo with 1 full coil. |
Rhizome(s) | absent. |
absent. |
2n | = 26. |
|
Potamogeton groenlandicus |
Potamogeton subsibiricus |
|
Phenology | Flowering late summer. | Fruiting early summer–late summer. |
Habitat | Ponds and lakes | Shallow water of ponds and lakes |
Elevation | 10–450 m (0–1500 ft) | 0–915 m (0–3000 ft) |
Distribution |
Greenland |
AK; MB; NT; NU; ON; QC; YT; Siberia |
Discussion | Of conservation concern. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 22. | FNA vol. 22. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | P. pusillus subsp. groenlandicus | P. porsildiorum |
Name authority | Hagström: Kongl. Svenska Vetenskapsakademiens Handlingar n.s. 55(5): 127. (1916) | Hagström: Kongl. Svenska Vetenskapsakademiens Handlingar n.s. 44:555(5):84. (1916) |
Web links |