5. Rhynchospora harveyi W. Boott (Harvey’s beaked rush)

Pl. 79 c, d; Map 303

Plants tufted. Aerial stems 25–65 cm long. Leaves basal and progressively reduced on the aerial stems, the leaf blade 4–25 cm long, 2.0–3.5 mm wide, flat. Inflorescences of 1–4 clusters of spikelets, mostly terminal, sometimes 1–2 axillary inflorescences also present. Spikelets 2.5–3.0 mm long, ovate to broadly elliptic in outline, mostly rounded at the tip, with 1(2) of the florets fertile. Spikelet scales 1.8–2.1 mm long, ovate to broadly elliptic with the midrib extended past the rounded tip as a curved, slender awn, brown. Perianth bristles 5–6, delicate and easily shed, much shorter than to about as long as the fruits, usually with inconspicuous, upwardly pointing barbs. Fruits with the tubercle 0.3–0.5 mm long, broadly triangular or depressed-conical with a distinctive raised basal margin, the main body 1.5–1.8 mm long, broadly ovate to broadly elliptic in outline, relatively turgid, the surface appearing honeycombed with a fine network of ridges and pits that are longer than to about as long as wide, reddish brown to black. June–July.

Uncommon in the southwestern quarter of Missouri, mostly in the Unglaciated Plains Division; also introduced in Dunklin County (southeastern U.S. west to Texas and Missouri). Sandstone and dolomite glades and moist areas of upland prairies.