Plants brown, dark brown to nearly black. Branch leaves lanceolate to linear-lanceolate, apex narrow and tubular, hyaline cells with 8-12 moderate-sized (more than 0.25 cell diameter) in mostly one row. Floating or stranded at margins of shallow lakes and ponds, rarely in seeps where probably constantly wet; low to moderate elevations; Nfld. and Labr. (Nfld.), N.S.; Ala., Ark., Del., Fla., Ga., La., Md., Miss., N.J., N.Y., N.C., S.C., Tenn., Tex., Va.