Sporobolus potosiensis

HABIT Perennial. Rhizomes elongated. Culms erect; 18–51 cm long. Leaf-sheaths glabrous on surface; outer margin hairy. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs; 0.1–0.3 mm long. Collar glabrous. Leaf-blades flat, or conduplicate, or involute; 6.2–24 cm long; 0.6–2.5 mm wide. Leaf-blade surface scaberulous and papillose; rough adaxially. Leaf-blade margins scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; 12–18 cm long; 4–9 cm wide. Primary panicle branches 3–8 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 0.2–2.2 mm long.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; subterete; 1.6–2.5 mm long; 0.5–1.1 mm wide; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes deciduous; reaching apex of florets. Lower glume lanceolate; 1–1.5 mm long; 0.75 length of upper glume; hyaline; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 1.3–2.1 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; 1.5–2.3 mm long; membranous; without keel; 1 -veined. Lemma apex acute. Palea readily splitting down midline; 1.6–2.2 mm long; 2 -veined. Palea keels approximate.

FLOWER Anthers 3; 1.2–1.4 mm long; yellow.

FRUIT Caryopsis with free soft pericarp; 0.9–1 mm long.

DISTRIBUTION North America: Mexico.

NOTES Eragrostideae. Wipff & Jones 2002.

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