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Image of leafy pondweed
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Leafy Pondweed

Potamogeton foliosus Raf.

Description

provided by eFloras
Rhizomes absent. Cauline stems slightly compressed, without spots, 4--75 cm; glands rarely present, black to gold, to 0.5 mm diam. Turions uncommon, lateral or terminal, 0.9--2.5 cm ´ 0.6--2 mm, soft; outer leaves 1--3 per side, base not corrugate, apex acute to apiculate; inner leaves rolled into hardened fusiform structure. Leaves submersed, ± spirally arranged, sessile, delicate; stipules persistent, inconspicuous, convolute, free from blade, greenish to brown or rarely white, not ligulate, 0.2--2.2 cm, delicate to fibrous, rarely shredding at tip, apex obtuse; blade pale green to olive-green, rarely somewhat reddish, linear, not arcuate, 1.3--8.2 cm ´ 0.3--2.3 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, acute to apiculate, rarely with bristle, lacunae rarely present, 0--2 rows each side of midrib; veins 1--3(--5). Inflorescences unbranched, emersed; peduncles not dimorphic, in axils of proximal, rarely distal leaves, recurved, clavate, 0.3--1.1(--3.7) cm; spikes not dimorphic, capitate to cylindric, 1.5--7 mm. Fruits pale green to olive-green or brown, obovate to nearly orbicular, turgid to concave, sessile, abaxially keeled, not laterally keeled, 1.4--2.7 ´ 1.1--2.2 mm, abaxial keel undulate, winglike; beak erect, 0.2--0.6 mm; sides without basal tubercles; embryo with 1 full spiral.
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cc-by-nc-sa-3.0
copyright
Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA
bibliographic citation
Flora of North America Vol. 22 in eFloras.org, Missouri Botanical Garden. Accessed Nov 12, 2008.
source
Flora of North America @ eFloras.org
editor
Flora of North America Editorial Committee
project
eFloras.org
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