di (G.) = two, + stachys (G.) = spikelet, thus "two-spikeletted". Often plants in this species have two spikelets.
WCM Protologue Reference:
(Rottb.) Kunth, Enum. Pl. 3: 444 (1841)
Vegetative parts: plants clumped or tufted (Sometimes forming fairy rings), 0.3–0.75 m tall, basal diameter 0.3–0.5 m, crown diameter 0.3–0.5 m, with rhizomes (these can be quite short, but are distinctive within the genus). Rhizome 3–6 mm in diam., culms 1–2 mm apart. Fertile culms unbranched, round (not compressed), solid or with a small central cavity, smooth or finely rugulose or finely warty, olivaceous, 0.3–0.75 m tall, diameter at base 0.4–1.5 mm, diameter at apex 0.4–0.8 mm. Branch axil indumentum absent. Clusters of sterile branches at the nodes of the fertile branches absent. Sheaths more than 1 per culm, persistent, with no abscission line, closely convoluted, 20–30 mm long, margins entire, olivaceous to brown, upper 1/3 in colour and texture similar to the lower 2/3, apical margins coriaceous, like the rest of the body, hyaline shoulders absent, apex, excluding the membranous lobes, acuminate. Sheath-mucro penicellate, straight and erect, 0–1 mm long, tightly convoluted and not very distinct from the culms. Sterile branch leaf-sheath 4–6 mm long, hyaline shoulder 1.5–2 mm long, leaf-blade 6–8 mm long; leaf blade 0.25–0.5 mm wide. Males: male inflorescence with 2–5 spikelets or 6–10 spikelets, paniculate, 30–60 mm long, 20–30 mm wide. Male inflorescence spathes persistent, like the floral bracts, coriaceous or cartilaginous, spathe subtending group of spikelets 2–3cm long and standing erect. Male flowers in spikelets. Male spikelets pendulous on flexible pedicels, oblong or obovate or orbicular, all straight, apex rounded, 10–13 mm, 6–11 mm, with 10–60 flowers, pedicels as long as the spikelets, flattened. Male bracts taller than flowers, 4.5–6 mm long, oblong, acute, margins entire, chartaceous, bract upper margin like body of bract, bract awn minute or absent, margins not frilly. Male flower 3–5 mm long. Male tepals sepals more rigid than petals, chartaceous, petals chartaceous, linear or oblong, inner tepals shorter than outer tepals or inner and outer tepals the same length (only slightly shorter). Male outer lateral tepals keeled or winged or conduplicate, glabrous. Anthers 1–2.25 mm long, included in the flowers. Pistillode present or absent. Females: female inflorescence 20–50 mm long, 6–15 mm wide, with 1 spikelet or 2–5 spikelets. Female spathes shorter than the spikelets, persistent, cartilaginous. Female spathellae inconspicuous or absent. Female spikelet sessile, oblong or elliptical or ovate, apex obtuse or acute, 20–40 mm long, with 15–25 flowers, with 0–1 sterile bracts. Female bracts at least twice as long as flowers, erect, 11–16 mm long, ovate (wide and clasping at the base), acute, chartaceous or cartilaginous, apical margin like rest of bract (lacerated), same as body of bract, margins entire, awn minute or absent. Female flower 3.5–4.5 mm long, regular, without a fleshy pedicel, six tepals. Female tepals chartaceous (cartilaginous at the base), glabrous and smooth, at least as tall as nut, wrapped around it and obscuring the surface, midrib raised, margins entire, apices acute, inner and outer whorls the same length. Female outer lateral tepals keeled or winged, wings entire, wider than body, hidden by bracts, or bracts are shorter than flowers, 3–4.5 mm long. Female odd outer tepal oblong, 3.5–4.5 mm long. Female inner tepals oblong, 3–4 mm long. Staminodes present. Styles flattened, white, 2. Style bases free. Ovary with 1 locule, indehiscent. Fruit: indehiscent fruits with a softer ovary wall. Perianth presence on fruits persistent, winged (styles break off leaving 2 'horns' on top of seed). Shape of winged dispersal unit oblong, narrower than long. Nut apex smooth, without a distinct cap, wall smooth, (1.6–)1.63(–1.64) mm long, (1.16–)1.17(–1.2) mm diam., shape in side view elliptical, shape in top view round in cross section, brown, mode of seed release for nutted plants bracts decay. Elaiosome absent.