Graphephorum

HABIT Perennial. Rhizomes absent, or short (1). Culms erect (1/1); 50–75–100 cm long. Ligule an eciliate membrane.

INFLORESCENCE Inflorescence a panicle.

Panicle open (1), or contracted (1).

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform (1), or linear (1), or oblong (1).

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with a barren rhachilla extension. Spikelets elliptic (1), or oblong (1); laterally compressed; 5–6.25–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite; pilose. Floret callus pubescent (1), or bearded (1).

GLUMES Glumes persistent; shorter than spikelet (1), or reaching apex of florets (1); thinner than fertile lemma. Lower glume elliptic; 0.9–0.95–1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface without pits. Lower glume apex acute (1), or acuminate (1). Upper glume elliptic; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute (1), or acuminate (1).

FLORETS Fertile lemma elliptic; membranous (1), or cartilaginous (1); of similar consistency above (1), or much thinner above (1); of similar consistency on margins (1), or much thinner on margins (1); keeled; wingless; 5 -veined. Lemma surface smooth (1), or asperulous (1); unwrinkled; without grooves. Lemma apex obtuse (1), or acute (1); muticous, or mucronate (1). Principal lemma awn subapical (1/1). Palea keels scaberulous.

FLOWER Ovary glabrous.

DISTRIBUTION North America.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.