Checklist » Potamogetonaceae » Potamogeton gramineus
Last updated 4/6/2009 by David Giblin.
Potamogeton gramineus L.[FNA22, HC, HC2]
grassy pondweed, variable pondweed

Publication: Sp. Pl. 1: 127. 1753 (as gramineum). 1753.

Origin: Native

selected vouchers: WTU

Notes: FNA22: "Seven hybrids, Potamogeton gramineus ´ P. nodosus (= P. ´ argutulus Hagström), P. gramineus ´ P. richardsonii (= P. hagstroemii A. Bennett [as hagstromii]), P. alpinus ´ P. gramineus (= P. ´ nericius Hagström), P. gramineus ´ P. perfoliatus (= P. ´ nitens Weber [P. ´ subnitens Hagström]), P. gramineus ´ P. natans (= P. ´ sparganiifolius Laestadius ex Fries), P. gramineus ´ P. illinoensis [= P. ´ spathuliformis (J. W. Robbins) Morong)], and P. gramineus ´ P. praelongus (= P. ´ vilnensis Galinis), have been described.

Three varieties were recognized (E. C. Ogden 19435) and treated (M. L. Fernald 1950). These varieties, Potamogeton gramineus var. gramineus, deletion}P. gramineus var. myriophyllus, and P. gramineus var. maximus, were said to be separated by the shape and size of the submersed leaves. We have studied many populations of this species in the field and have observed on several occasions that a single population has leaf morphology variable enough to include all three varieties. We have, , therefore , chosen not to recognize any infraspecific categories for this species."

KZ99 mistakently places German P. heterophyllus as a synonym of New World P. illinoensis

References: (none)

Synonyms & Misapplied Names:
Potamogeton gramineus L. var. maximus Morong[VPPNW1]
Potamogeton gramineus L. var. myriophyllus J.W. Robbins[IMF6]
Potamogeton heterophyllus Schreb.