T: [USA, Texas] 'Galveston island auf feuchtem Muschelsand', 4 Apr 1846, Römer; holo: B, destroyed.
Perennials, (15–) 50–150 (–230) cm long; rhizome creeping, stout, with internodes usually short; intravaginal shoots absent. Cataphylls 2–5, to 10 cm long; blade tiny. Leaves 40–125 cm long, 1.5–4 mm in diam. Lower bract (2–) 5–20 (–90) cm long, including a sheath 1.5–3 (–5) cm long; middle bracts small, amplexicaul, with blade ±absent; bracts subtending heads considerably shorter than flowers. Plant gynodioecious, with female and ±hermaphrodite clones. Inflorescence (2–) 5–20 (–45) × 3–6 (–12) cm, usually lax, ±broad; heads (15–) 30–100 (–200), 2–8 (–25)-flowered. Tepals 2.2–3.5 mm long, subequal, with margins scarious; outer tepals ±narrowly ovate, with base keeled, distally scarious margins slightly broader and mucro up to 0.3 mm long; inner tepals oblong, obtuse, with scarious part broad near apex. Stamens 6, equalling tepals or slightly shorter, rudimentary in pistillate flowers; anthers 1.4–1.7 (–2.0) mm long, 5–7 times as long as filaments; stigmas 1.5–2.5 mm long. Capsule in hermaphrodite flowers 2.5–3 mm long, in pistillate flowers 3–5 mm long, ±exceeding tepals, broadly trigono-ellipsoidal, obtuse, light to dark brown, glossy, trilocular with thick placentas; mucro 0.1–0.3 mm long. Seeds 0.5–0.7 mm long, or 0.6–0.8 mm long including appendages, 0.3–0.4 mm broad, ±ellipsoidal, yellowish brown, c. 25-striate; appendages indistinct or with one to 0.1 mm long. Fig. 47.