GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Chondrosum elatum

HABIT Perennial; caespitose. Rootstock evident. Culms erect; 70–120(–140) cm long. Lateral branches lacking. Leaf-sheaths glabrous on surface; outer margin glabrous, or hairy. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs; 0.5 mm long. Leaf-blades flat, or conduplicate, or involute; 20–50 cm long; 3–4 mm wide. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 9–20; borne along a central axis; unilateral; 2–8 cm long; bearing 40–100 fertile spikelets on each. Central inflorescence axis 20–40 cm long. Rhachis semiterete; tuberculate on margins; ciliate on margins; terminating in a spikelet. Rhachis hairs 2–3 mm long. Spikelet packing broadside to rhachis; crowded.

Spikelets pectinate; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 3–4 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; reaching apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 3–4 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex dentate; 2 -fid; acuminate; mucronate. Upper glume lanceolate; 3–4 mm long; 1.5 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein tuberculate; ciliate. Upper glume lateral veins absent. Upper glume apex dentate; 2 -fid; acuminate; mucronate.

FLORETS Fertile lemma oblong; 2–2.5 mm long; coriaceous; keeled; 3 -veined. Lemma surface pubescent; hairy below. Lemma apex lobed; 3 -fid; awned; 3 -awned. Principal lemma awn 2–4 mm long overall. Lateral lemma awns arising on inner edge of lobes; 2–4 mm long; subequal to principal. Palea 2 -veined. Palea apex awned. Rhachilla extension pilose; hairy at tip. Apical sterile florets 1 in number; barren; rudimentary. Apical sterile lemmas awned; 3 -awned. Apical sterile lemma awns 3 mm long.

FRUIT Caryopsis with adherent pericarp; obovoid; 1 mm long.

DISTRIBUTION North America: Mexico.

NOTES Cynodonteae. Gould.

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