Eleocharis tenuis var. pseudoptera
Rhodora 41: 65. 1939.
Rhizomes 1–2 mm thick, longer internodes 5–10 mm, scales sometimes decaying to fibers. Culms sharply 4– (5–6) -angled, often deeply sulcate and thus “winged,” to 0.8 mm wide. Leaves: distal leaf-sheaths usually with stout apical tooth 0.4–0.6 (–0.9) mm. Achenes usually lemon yellow to dark yellow, nearly equilaterally trigonous, usually cancellate at 10X, with 10–14 obscure to clearly evident depressions in each vertical series. Tubercles mostly greatly depressed, much lower than wide. 2n = 38, 39.
Phenology: Fruiting spring (Mar–Apr) in South, early summer (Jun–Jul) in North.
Habitat: Wet, fresh, often calcareous meadows, swales, springy places, woods, prairie, serpentine barrens, ditches
Elevation: 10–300 m
N.S., Que., Conn., Del., D.C., Ga., Ind., Ky., La., Md., Miss., N.J., N.Y., N.C., Pa., Tenn., Vt., Va.
I have not seen voucher specimens for the chromosome count by L. J. Harms (1972) for Eleocharis elliptica var. pseudoptera.