Sporobolus coahuilensis

HABIT Annual. Culms geniculately ascending; 15–60 cm long. Culm-internodes distally glabrous. Leaf-sheaths mostly shorter than adjacent culm internode; glabrous on surface. Ligule a fringe of hairs; 0.5–1 mm long. Leaf-blades spreading; 4–12 cm long; 1.5–6 mm wide. Leaf-blade surface pilose; sparsely hairy; hairy adaxially; with tubercle-based hairs.

INFLORESCENCE Inflorescence a panicle.

Panicle open, or contracted; ovate; 6–22 cm long; 5–13 cm wide. Primary panicle branches whorled at most nodes.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; 2–8 mm long.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; subterete; 1–1.5 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes deciduous; reaching apex of florets. Lower glume lanceolate; 0.5 mm long; 0.33 length of upper glume; hyaline; without keels. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 1.4–1.5 mm long; 1 length of adjacent fertile lemma; membranous; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 1.3–1.4 mm long; membranous; without keel; 1 -veined. Lemma apex acute. Palea readily splitting down midline; 1–1.3 mm long; 2 -veined. Palea keels approximate.

FRUIT Caryopsis with free soft pericarp; ellipsoid; 0.6–0.9 mm long; light brown. Embryo 0.33 length of caryopsis.

DISTRIBUTION North America: Mexico.

NOTES Eragrostideae. Valdes 2002.

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