gossypinus (L.) = cottony. Referring to the tufts of hair/wool emerging from the leaf sheaths.
WCM Protologue Reference:
Mast., Bot. Jahrb. Syst. 29(66): 3 (1900)
Vegetative parts: plants tufted or tangled, 0.2–0.45 m tall, basal diameter 0.01–0.4 m, crown diameter 0.1–0.5 m, compact, without spreading rhizomes or stolons or with stolons. Fertile culms sparingly branched, round (not compressed), solid or with a small central cavity, smooth or roughly warty (culms of some specimens are completely smooth while others have distinctly papillose culms), green or olivaceous, 0.2–0.45 m tall, diameter at base 0.6–1.4 mm, diameter at apex 0.5–0.8 mm. Branch axil indumentum present. 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, 7–21 mm long, margins entire, orange to reddish-brown often with a coppery sheen, upper quarter of the sheath and edges tan, upper 1/3 in colour and texture similar to the lower 2/3 or abruptly different from the base, and soon decaying, apical margins broadly membranous, hyaline shoulders tall, acute, apex, excluding the membranous lobes, acute or obtuse or truncate. Sheath-mucro penicellate, straight and erect, 4–23 mm long. Males: male inflorescence with 2–5 spikelets or 6–10 spikelets, racemose, 8–65 mm long, 1–8 mm wide. Male inflorescence spathes persistent, as tall as spikelets, cartilaginous. Male spathellae inconspicuous or absent. Male flowers in spikelets. Male spikelets erect on stiff pedicels or sessile, elliptical, apex acute or undifferentiated, 8–18 mm, 1–3 mm, with 5–12 flowers, pedicels absent ie spikelets sessile. Male bracts taller than flowers, 6–8 mm long, oblong or elliptical (relatively broad in the middle), rounded, margins entire, coriaceous or cartilaginous, bract upper margin membranous, thinner texture than the body, bract awn less than half as long as the bract body. Male flower 3.5–6 mm long. Male tepals sepals and petals the same rigidity, chartaceous, oblong or elliptical (outer tepals are oblong and inner ones elliptical), inner and outer tepals the same length. Male outer lateral tepals conduplicate, keel sparsely villous. Anthers 1.5–2 mm long, exserted from the flowers. Females: female inflorescence interrupted or linear, 6–50 mm long, 1–7 mm wide, with 1 spikelet or 2–5 spikelets or 6–10 spikelets. Female spathes shorter than the spikelets, persistent, coriaceous or cartilaginous. Female spathellae inconspicuous or absent. Female spikelet sessile, oblong or undifferentiated, apex undifferentiated, 6–23 mm long, with 5–15 flowers, with 0 sterile bracts. Female bracts taller than flowers, erect, 7–10 mm long, oblong, obtuse or acute, coriaceous or cartilaginous, apical margin membranous, same as body of bract, awn less than half as long as the bract body or between half and as long as the bract body. Female flower 4–7 mm long, without a fleshy pedicel, six tepals. Female tepals cartilaginous, keels of lateral sepals densely villous, midrib raised, margins entire, apices acute, inner and outer whorls the same length. Female outer lateral tepals conduplicate, 3.5–5 mm long. Female odd outer tepal oblong or ovate, 3.5–5 mm long. Female inner tepals ovate, 3.5–5 mm long. Staminodes absent. Styles feathery, white, 2. Style bases fused to form a pillar, more or less villous. Ovary dehiscent. Fruit: seed (1.52–)1.66(–1.84) mm long, (0.96–)1.19(–1.32) mm in diameter, shape in side view elliptical, shape in diameter round in cross section, translucent or silvery or white (seeds are silvery-white and semi-translucent, so that the yellowish/brown colour underneath shines through to various degrees), pitted.