Potamogeton subsibiricus

Hagström

Kongl. Svenska Vetenskapsakademiens Handlingar n.s. 44:555(5):84. 1916.

Common names: Yenissei River pondweed potamot de l’Ilenissei
Synonyms: Potamogeton porsildiorum Fernald
Treatment appears in FNA Volume 22.

Rhizome absent. Cauline stems compressed-filiform, without spots, to 50 cm; glands white, 0.3–0.5 mm diam. Turions 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, 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, axillary, erect, cylindric, 1.7–3.5 cm; spikes not dimorphic, cylindric, 10–30 mm. Fruits 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.


Phenology: Fruiting early summer–late summer.
Habitat: Shallow water of ponds and lakes
Elevation: 0–915 m

Distribution

V22 5-distribution-map.jpg

Man., N.W.T., Ont., Nunavut, Que., Yukon, Alaska, Siberia

Discussion

Selected References

None.

Lower Taxa

None.

"shortened" is not a number."not elongating" is not a number."less" is not a number.

... more about "Potamogeton subsibiricus"
nearly acute +  and mucronate +
Robert R. Haynes +  and C. Barre Hellquist +
Hagström +
tapering +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
3.5 cm35 mm <br />0.035 m <br /> (9.5 cm95 mm <br />0.095 m <br />) +
elliptic;ovate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
compressed-filiform +
0 cm0 mm <br />0 m <br /> (50 cm500 mm <br />0.5 m <br />) +
Yenissei River pondweed +  and potamot de l’Ilenissei +
Man. +, N.W.T. +, Ont. +, Nunavut +, Que. +, Yukon +, Alaska +  and Siberia +
0–915 m +
reddish-brown +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
keeled +, ridged +, compressed +  and oblong-obovoid +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (?) +  and 0.05 cm0.5 mm <br />5.0e-4 m <br /> (?) +
Shallow water of ponds and lakes +
axillary +  and terminal +
cylindric +  and capitate +
undifferentiated +
arranged +  and 2-ranked +
submersed +
not crispate +
orthotropous +
not pedunculate +
emersed +  and submersed +
cylindric +  and capitate +
not spiraling +
not dimorphic +
cylindric +
1.7 cm17 mm <br />0.017 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
Fruiting early summer–late summer. +
short-stipitate +  and stipitate +
4 +  and 1 +
Kongl. Svenska Vetenskapsakademiens Handlingar +
auriculate +  and not auriculate +
not persisting +
not dimorphic +
emersed +  and submersed +
cylindric +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
epitepalous +
compressed;terete +
inconspicuous +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
not fibrous +
Potamogeton porsildiorum +
Potamogeton subsibiricus +
Potamogeton +
species +
3.5 cm35 mm <br />0.035 m <br /> (9.5 cm95 mm <br />0.095 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
9 (?) +  and 17 (?) +
caulescent +, not rhizomatous +  and rhizomatous +
annual +  and perennial +