Aquatic and Wetland Vascular Plants of the Northern Great Plains
Lycopus L. -- Bugleweed
Erect to decumbent perennials, nonaromatic or only faintly aromatic, often stoloniferous and/or tuberiferous. Leaves sessile or short-petioled, coarsely serrate or incised-toothed, reduced upward, usually punctate. Flowers small, not showy, clustered in the axils of middle and upper leaves, often appearing verticillate, white to pinkish, the calyx and corolla often punctate on the outside; calyx regular, 5-toothed; corolla nearly regular, 4-lobed, the tube short, hairy internally at the throat, the upper lobe formed by the fusion of 2 lobes, tending to be broader than the other 3 lobes, often emarginate; functional stamens 2, exserted, the upper pair absent or reduced to staminodes. Nutlets broadened upward to a truncate or rounded crest, sometimes undulate or slightly tuberculate on the crest, nearly flat on the outer surface, with a corky ridge on each margin and often across the top, the inner surface convex and punctate with yellowish-viscid glands.
References:
Henderson, N. C. 1962. A taxonomic revision of the genus Lycopus. Amer.
Midl. Naturalist 68:95-138.
Hermann, F. J. 1936. Diagnostic characteristics in Lycopus. Rhodora 38:
373-375.
| Lead | Characteristic | Go To |
| 1 | Calyx lobes slender, firm, sharply pointed, 1-3 mm long, surpassing the nutlets. | Lead 2 |
| 1 | Calyx lobes broad, triangular to ovate, soft, obtuse to bluntly acute, 0.5-1 mm long, shorter than to about equaling the nutlets. | L. uniflorus |
| 2 | Nutlets rounded apically on the outer margin, mostly 1-1.5 mm long; leaves short-petioled to subsessile, the blades irregularly incised-toothed to subpinnatifid. | L. americanus |
| 2 | Nutlets truncate apically on the outer margin, mostly 1.5-2 mm long; leaves sessile, the blades rather regularly and coarsely serrate. | L. asper |
- 1. Lycopus americanus Muhl. ex Bart.
-- American bugleweed
- 2. Lycopus asper Greene -- Rough bugleweed
- 3. Lycopus uniflorus Michx.
- 2. Lycopus asper Greene -- Rough bugleweed
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