Luzula atrata Edgar

Perennials, 12–20 (–30) cm tall, slender, loosely caespitose; rhizome creeping-ascending; stolons short. Basal leaves canaliculate, often involute, to c. 9 cm long, narrow, c. 1.5–2.0 (–2.5) mm wide; cauline leaves 1 (–2), to c. 3 cm long; margins subglabrous, ±swollen, sparsely papillose-serrulate; apex obtuse. Lower bract subherbaceous, erecto-patent, 0.8–1.5 cm long; margins distinctly papillose-serrulate; apex acute, ±equalling inflorescence. Inflorescence a single dark head 0.7–1.0 cm in diam., of 1–4 indistinct sessile clusters. Bracteoles ovate, scarious with dark brown base, c. 1.0–1.5 mm long, sparsely fimbriate. Tepals ±equal, narrowly lanceolate, acuminate, (2.2–) 2.4–2.6 (–2.8) mm long, blackish-brown; margins indistinct or narrow and paler brown; apex often paler. Stamens 6; anthers (0.4–) 0.5–0.7 mm long; filaments 0.6–0.8 mm long; style c. 0.2 mm long; stigmas 1.0–1.5 mm long. Capsule oblong-ellipsoid, acute, subequalling perianth, ±blackish brown, distally papillose; capsule segments 2.2–2.3 × 1.1–1.2 mm. Seeds ellipsoid, dark brown, 1.0–1.1 mm long, c. 0.6 mm wide; appendage c. 0.2 mm long, fibrillate.