Plants perennial; rhizomatous, sometimes producing aquatic leaves when submerged. Culms (5)10-100 cm, erect, glabrous, rooting at the lower nodes; nodes glabrous. Sheaths of aquatic leaves closed to near the apices, translucent, pale pinkish-brown; collars inconspicuous; ligules acute; blades pinkish-brown. Sheaths of aerial leaves usually closed for over 1/2 of their length, sometimes open to the base, opaque, green to olive-green, glabrous; collars conspicuous as a zone of contrasting color; auricles absent; ligules membranous, truncate, lacerate; blades usually flat, glabrous, upper blades conspicuously longer than the lower blades. Inflorescences open panicles; branches stiff and ascending to pendulous, glabrous. Spikelets pedicellate, somewhat laterally compressed; florets (1)2-7(9); rachillas prolonged beyond the uppermost floret, glabrous; disarticulation above the glumes. Glumes subequal, broadly lanceolate to ovate, membranous to subcoriaceous, glabrous, 1-3(-5)-veined, acute to obtuse; calluses short, blunt, bearded to almost glabrous; lemmas ovate, glabrous, membranous to subcoriaceous, with 3(5) obscure veins, apices entire, obtuse; paleas subequal to the lemmas; lodicules 2, free, glabrous, toothed or entire; anthers 3; ovaries glabrous. Caryopses falling free; hila broadly ovate, 1/6-1/5 the length of the caryopses. x = 7. From the Greek arktos, north, and philia, loving.

Arctophila is a monotypic, but highly polymorphic, holarctic genus closely related to Dupontia.

1.   Arctophila fulva (Trin.) Andersson
Pendant Grass, Arctophile Fauve

Culms (5)10-80(100) cm. Ligules (1)2-6(8) mm; blades 2-23 cm long, 1-5(10) mm wide. Panicles 3-20 cm long, (1.5)3-11 cm wide. Spikelets 2.5-7(8) mm; florets (1)2-7(9). Glumes 1.5-4(5) mm; lower glumes exceeded by the lowest floret; upper glumes shorter to longer than the lowest floret; lemmas 2.5-4 mm; paleas (1)1.8-4 mm; anthers 1.2-3 mm. Caryopses 1.5-2.2 mm. 2n = 42, 63.

Arctophila fulva grows as an emergent species in shallow, standing water or along slow-moving streams, wet meadows, marshes, and saturated soils of low arctic and subarctic regions, where it often forms pure stands. It is one of the few grasses that develop aquatic leaves. Field observations indicate that under some environmental conditions, A. fulva can propagate vegetatively from detached stems that have over-wintered (Aiken and Buck 2002). In the Flora region, it grows from Alaska through the Yukon, Northwest Territories, Nunavut, Ontario, Quebec, and Labrador to Greenland. Its range extends across Eurasia to arctic Scandinavia. It forms a sterile hybrid, ×Arctodupontia scleroclada, with Dupontia fisheri.