Plants perennial; stoloniferous, often forming extensive low mats. Culms 2–15 cm, erect or decumbent. Ligules 0.4–1.5 mm, acute, obtuse, or truncate, entire; blades 0.4–2.2 mm wide when flat, 0.2–1 mm in diam-eter when involute. Panicles usually not developed, if devel-oped, 1–7 cm, diffuse, lower branches ascending, spikelets usually confined to the distal 1/3; pedicels scabrous, usually with tumid epidermal cells. Spikelets 6–9 mm, with 3–6(7) florets. Glumes rounded or slightly keeled over the back, veins obscure or distinct, apices acute or obtuse; lower glumes 1.5–2.2 mm; upper glumes 2.3–2.8 mm; calluses glabrous or almost so; lemmas 3.2–3.8(4.5) mm, membranous, usually glabrous, occasionally sparsely hairy, backs rounded, 5-veined, veins obscure, not extending to the margins, apices acute or rounded, apical margins whitish, hyaline, smooth, entire; palea veins glabrous; anthers (1.5)2–2.5 mm, almost always indehiscent, mature pollen rarely produced. Caryopses rarely developed. 2n = 21, 28.
Puccinellia phryganodes is a widespread and common circumpolar arctic species that grows on seashores at or near the high tide line, in wet saline meadows, and in saline or brackish marshes.