403. Carex cryptocarpa C. A. Meyer, Mém. Acad. Imp. Sci. St.-Pétersbourg Divers Savans. 1: 226. 1831.
隐果薹草 yin guo tai cao
Carex lyngbyei Hornemann subsp. cryptocarpa (C. A. Meyer) Hultén; C. lyngbyei subsp. prionocarpa (Franchet) Kitagawa; C. prionocarpa Franchet.
Rhizome with stout stolons. Culms 30-120 cm tall, stout, slightly smooth, clothed at base with reddish purple, lustrous, bladeless sheaths. Leaves shorter than culm, blades broadly linear, 5-10 mm wide, flat, margins slightly involute. Involucral bracts leaflike, lower 2 or 3 surpassing inflorescence. Spikes 5-7, remote; upper 2 or 3 spikes male, fusiform or clavate, 6-7 cm; remaining spikes female, usually with male flowers at apex, cylindric, 2-8 × 0.8-1.2 cm, many flowered, with peduncles up to ca. 10 cm, smooth, pendent. Female glumes dark brown-purple, lanceolate or oblong-lanceolate, pale 1-veined costa excurrent into a mucro. Utricles gray-green, becoming light brown, ca. 1/2 as long as glume, ovate, biconvex, ca. 3 mm, slender, 6-8-veined, base shortly stipitate, apex gradually attenuate into a beak, orifice truncate. Nutlets brown, tightly enveloped, elliptic; style base not thickened; stigmas 2.
Marshes, meadows, riversides [Japan, Russia (Far East); North America (Alaska)].
No specimens from China have been seen by the present authors. Standley et al. (Fl. N. Amer. 23: 383-384. 2002) suggested that Asian populations are a different species from North American Carex lyngbyei and are appropriately given species status.