Cathestecum prostratum

HABIT Annual. Culms prostrate; slender; 4–35 cm long. Lateral branches ample. Leaf-sheaths glabrous on surface. Ligule a fringe of hairs; 0.3 mm long. Leaf-blades 1–5 cm long; 1–2 mm wide. Leaf-blade surface scabrous; rough adaxially; pilose; sparsely hairy; hairy adaxially. Leaf-blade margins scabrous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes; terminal and axillary.

Racemes 4–8; borne along a central axis; cuneate; 0.4 cm long; bearing a triad of spikelets. Central inflorescence axis 3 cm long; tip subulate. Rhachis deciduous from axis; terminating in a barren extension; extension bristle-like; extension 2 mm long.

Spikelets in threes. Fertile spikelets pedicelled; 1 in the cluster. Companion sterile spikelets sessile; 2 in the cluster. Pedicels oblong.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; cuneate; laterally compressed; 3 mm long; as long as fertile; deciduous with the fertile. Companion sterile spikelet glumes membranous; villous; acuminate; mucronate. Companion sterile spikelet lemmas 2; 2–3 mm long; lobed (3-fid); several-awned (3 awns); with 1 mm long awn.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 4 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes dissimilar; reaching apex of florets; similar to fertile lemma in texture. Lower glume flabellate; 0.5–1 mm long; 0.1–0.2 length of upper glume; membranous; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume lanceolate; 4 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume surface villous. Upper glume apex obtuse, or acute; mucronate.

FLORETS Fertile florets female. Fertile lemma oblong; 3–4 mm long; membranous; without keel; 3 -veined. Lemma surface pilose. Lemma margins ciliate. Lemma apex lobed; 3 -fid; with outer lobes shorter and with central lobe bidentate; incised 0.25 of lemma length; awned; 3 -awned. Principal lemma awn from a sinus; 1–2 mm long overall; limb ciliate. Lateral lemma awns arising on margin of lemma; 1–2 mm long; subequal to principal; ciliate. Palea apex awned; awns 2 mm long. Apical sterile florets 2 in number; male, or barren; oblong. Apical sterile lemmas lobed; 3 -fid; awned; 3 -awned. Apical sterile lemma awns 4–5 mm long; ciliate.

DISTRIBUTION North America: Mexico.

NOTES Cynodonteae. Swallen.

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