GrassBase - The Online World Grass Flora


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

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

Chondrosum barbatum

HABIT Annual, or perennial; caespitose. Culms geniculately ascending, or decumbent; 5–30 cm long. Leaves mostly basal. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs. Leaf-blades 1.5–7 cm long; 1–3(–4) mm wide. Leaf-blade surface smooth, or scaberulous; rough adaxially.

INFLORESCENCE Inflorescence composed of racemes.

Racemes (2–)4–8(–9); borne along a central axis; unilateral; 1–3 cm long; bearing 25–40 fertile spikelets on each. Central inflorescence axis 2–12 cm long. Rhachis semiterete; smooth on surface, or scabrous on surface. 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; 2.5–3 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; 2 mm long; 0.6–0.8 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex dentate; 2 -fid; acuminate; mucronate. Upper glume lanceolate; 2.5–3 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex dentate; 2 -fid; acuminate; mucronate.

FLORETS Fertile lemma oblong; 2.5–3 mm long; coriaceous; keeled; 3 -veined. Lemma surface glabrous, or pubescent; hairy below. Lemma margins pubescent; hairy below. Lemma apex lobed; 3 -fid; with central lobe bidentate; awned; 3 -awned. Principal lemma awn 0.5–3 mm long overall. Lateral lemma awns arising on inner edge of lobes, or on margin of lemma; 0.5–3 mm long; subequal to principal. Palea 2 -veined. Palea surface pubescent; hairy on flanks. Palea apex dentate; 4 -fid. Rhachilla extension pilose; hairy at tip. Apical sterile florets 2 in number; barren; cuneate; 0.5–1 mm long. Apical sterile lemmas lobed; 2 -fid; obtuse; awned; 3 -awned. Apical sterile lemma awns 0.5–3 mm long.

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

DISTRIBUTION North America: southwest USA, south-central USA, and Mexico. South America: southern South America.

NOTES Cynodonteae. Gould.

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