| Locality: | United States. Kentucky. Clark: Abandoned limestone quarry, 0.9 mile west of junction with Ky. 1924 on Ky. 418 (Old Athens-Boonesborough road), adjacent to Kentucky River; |
| Habitat: | Abandoned limestone quarry. Nearly cosmopolitan free-floating species, frequent in Typha/Scirpus/Salix/Equisetum swamp. Associates: Typha latifolia, Scirpus cyperinus, Salix exigua, S. pendulus, S. atrovirens, Equisetum arvense, E. hyemale, Alisma subcordatum, Carex cristatella, Carex tribuloides, Lycopus sp., Mentha sp. |