Description from Flora of China
Elyna capillifolia Decaisne in Jacquemont, Voy. Inde 4(Bot.): 173. 1844; Kobresia brunnescens Boeckeler; K. capilliformis N. A. Ivanova; K. elata Boeckeler; K. kashgarica Dickoré; K. macrolepis Meinshausen; K. ×ovczinnikovii T. V. Egorova; K. yushuensis Y. C. Yang.
Rhizomes short. Basal sheaths prominent and persistent, brown to dark brown, often shiny, apices and margins sometimes fibrillose, not retaining dried leaf blades. Culms densely tufted, erect, slightly stiff, obtusely trigonous, (5-)10-45 cm tall, slender, 0.6-1 mm in diam. Leaves basal, shorter than to equaling culms; blade stiffly erect, filiform (tubular in section), margin involute, 0.7-1 mm wide. Inflorescence a dense spike, lowest spikelets sometimes slightly distant, brown, narrowly cylindric, 2-4.5 × 0.2-0.4 cm; lowest involucral bract glumelike, apex aristate or not; terminal few spikelets male, lower ones bisexual. Bisexual spikelets with 1 basal female floret and (1 or)2-4 distal male florets. Glumes pale brown to dark brown, with yellowish green to green midvein, usually broadly oblong-lanceolate to ovate, 4-6 × 2.5-2.8 mm, papery, midvein narrow or wide, margin broadly hyaline, apex usually rounded. Prophylls brown, oblong, lanceolate, or elliptic, 2.5-5.3 × 0.8-1.8 mm, membranous, 1- or 2-keeled, keels smooth or slightly scabrid, margins free nearly to base, apex rounded or truncate. Nutlets brown to dark brown, elliptic to obovoid, trigonous, (2-)2.5-3.5 × 0.8-1.6 mm, shortly beaked, subsessile. Stigmas (2 or)3. Fl. and fr. May-Sep.
Kobresia kashgarica, described from high elevations in Xinjiang, appears to be an extremely reduced form of K. capillifolia but is also similar to K. myosuroides subsp. bistaminata. Reduced forms of many species can be found; they appear to represent phenotypic responses to extreme habitats and (while often difficult to identify) do not merit specific treatment.
Dry and open grassy and rocky slopes, slopes in Juniperus scrub, disturbed slopes in Picea forests, grassy areas within Abies forests; 2000-4800 m. Gansu, Qinghai, Sichuan, Xinjiang, Xizang [Afghanistan, Bhutan, India (Himachal Pradesh, Sikkim), Kashmir, Kazakhstan, Kyrgyzstan, Mongolia, Nepal, Pakistan, Tajikistan].