Plants: medium-sized to large (sometimes when submerged), not turgid, green, red, purplish red, dark brownish red, or blackish red. Stems: sparsely and irregularly branched or sometimes ± pinnate, shoot apices not hooked; hyalodermis well developed, complete. Stem: leaves ovate or ovate-lanceolate, gradually or sometimes abruptly narrowed to apex, ± suddenly curved distally, concave, 0.5–1 mm wide; apex acuminate or long-acuminate, sometimes apiculate; costa single, ending beyond mid leaf; alar cells 2–10; medial laminal cells (shorter 1/2 of leaf) 61–140(–179) µm, cell ends short or long fusiform-narrowed, rarely rounded to almost square. Sexual: condition autoicous. Capsule: with exostome external surface more than 40–50% cross striolate basally.
Mountains, intermediately mineral-rich and often spring-influenced fens, small periodically water-filled depressions, shores, submerged. low to high elevations (0-3100 m). Greenland, St. Pierre and Miquelon, Alta., B.C., Man., Nfld. and Labr., N.W.T., Nunavut, Ont., Que., Sask., Yukon, Alaska, Colo., Idaho, Mich., Minn., Mont., Ohio, Vt., Wis., Wyo., South America, Eurasia, s Africa, Pacific Islands (New Zealand, Papua New Guinea), Antarctica.
Scorpidium revolvens often has been confused with 2. S. cossonii; the differences between these species are discussed under the latter.