Aristida mutabilis Trin. & Rupr.

Loosely tufted annual; culms (10–)30–70 cm. high, glabrous.. Leaf-blades linear, 6–14 cm. long, narrow or convolute; sheaths glabrous, those at the base of the plant laterally compressed, the auricles bearded or not.. Panicle narrowly ovate, 12–20 cm. long, loose or ± contracted, the spikelets congested in narrow spikes at the tips of the main branches.. Spikelets grey or pallid; glumes typically subequal, lanceolate, scaberulous on the keel and sometimes also on the flanks, the lower 4–5 mm. long, the upper 6–7 mm. long, acute or apiculate, less often with a short awn-point; lemma terete, 4–5 mm. long, scabrid upwards; callus linear, 1–1.5 mm. long, finely obtuse at the tip; column 2–5 mm. long, articulated just below the branching point of the awns; awns 10–30 mm. long, slender, parallel or divergent.