grandis (L.) = large. Referring to the relatively tall plants, but even taller inflorescences.
WCM Protologue Reference:
(Spreng. ex Nees) Kunth, Enum. Pl. 3: 475 (1841)
Vegetative parts: plants tufted, 0.9–1.5 m tall, basal diameter 0.3–1 m, crown diameter 0.5–1.5 m, compact, without spreading rhizomes or stolons. Fertile culms branching, round (not compressed), solid or with a small central cavity, smooth or finely warty, olivaceous, 0.6–1.2 m tall, diameter at base 3–6 mm, diameter at apex 1.5–2 mm. Clusters of sterile branches at the nodes of the fertile branches absent. Sheaths more than 1 per culm, persistent, with no abscission line, loosely convoluted, 20–90 mm long, margins entire, greenish-brown (sometimes with a mettalic hue) and yellow to reddish-brown margins, upper 1/3 in colour and texture similar to the lower 2/3, apical margins narrowly membranous, hyaline shoulders absent, apex, excluding the membranous lobes, acute. Sheath-mucro penicellate, straight and erect, 0.5–1.3 mm long. Males: male inflorescence with 21–50 spikelets or 50–100 spikelets, paniculate, 50–160 mm long, 15–25 mm wide. Male inflorescence spathes caducous, taller than spikelets, cartilaginous, Rich golden-brown in colour. Male spathellae inconspicuous or absent. Male flowers in spikelets. Male spikelets erect on stiff pedicels or sessile, oblong or ovate or undifferentiated, apex undifferentiated, 7–12 mm, 3–8 mm, with 3–5 flowers, pedicels shorter than the spikelets or as long as the spikelets, terete or angular. Male bracts shorter than flowers, 1.5–3 mm long, oblong, acute, chartaceous, bract upper margin like body of bract, bract awn minute or absent or less than half as long as the bract body. Male flower 3–4 mm long. Male tepals sepals and petals the same rigidity, chartaceous, oblong, inner tepals longer than outer tepals. Male outer lateral tepals as other tepals, glabrous. Anthers 1.8–2.2 mm long, included in the flowers. Females: female inflorescence linear, 70–140 mm long, 10–20 mm wide, with 21–50 spikelets. Female spathes longer than the spikelets, obscuring spikelet, persistent, bony or cartilaginous. Female spathellae inconspicuous or absent. Female spikelet pedicel simple or pedicel sparsely branching, undifferentiated, apex truncate or rounded or obtuse or acute, 5–6.7 mm long, with 1–2 flowers, with 0 sterile bracts. Female bracts shorter than flowers, erect, 2.5–3.5 mm long, ovate, acuminate, chartaceous, apical margin like rest of bract, same as body of bract, awn minute or absent. Female flower 5–6.7 mm long, without a fleshy pedicel, six tepals. Female tepals bony or coriaceous, glabrous and smooth, at least as tall as nut, wrapped around it and obscuring the surface, midrib raised, margins entire, apices obtuse or acute, inner and outer whorls the same length. Female outer lateral tepals like other tepals or conduplicate, hidden by bracts, or bracts are shorter than flowers, 4–6 mm long. Female odd outer tepal oblong, 4–6 mm long. Female inner tepals oblong or square, 4–6 mm long. Styles 2. Style bases seated on a stylopodium. Ovary with 1 locule, indehiscent. Fruit: indehiscent fruits with a softer ovary wall. Perianth presence on fruits persistent, papery to leathery, not winged. Nut apex smooth, without a distinct cap, wall tuberculate, (4.4–)5.25(–5.68) mm long, (2.56–)2.97(–3.28) mm diam., shape in side view oblong, shape in top view elliptical in cross section, brown or black. Elaiosome absent.