Apera interrupta

HABIT Annual; culms solitary, or caespitose. Culms erect, or geniculately ascending; 10–70 cm long; 2–4 -noded. Leaf-sheaths smooth. Ligule an eciliate membrane; 2–5 mm long. Leaf-blades convolute; 5–12 cm long; 0.5–4 mm wide. Leaf-blade surface scabrous; rough adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; ovate; interrupted; 3–20 cm long; 0.4–1.5 cm wide. Primary panicle branches appressed, or ascending; bearing spikelets almost to the base.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 0.5–2 mm long; scaberulous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 2–2.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; shiny. Lower glume lanceolate; 1–2 mm long; 0.7–0.8 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 2–2.5 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scaberulous. Upper glume apex acute.

FLORETS Fertile lemma ovate; 2–2.5 mm long; membranous; without keel; 5 -veined. Lemma surface scaberulous; rough above. Lemma apex acute; awned; 1 -awned. Principal lemma awn subapical; straight; 4–10 mm long overall. Palea 0.75 length of lemma; 2 -veined.

FLOWER Anthers 3; 0.3–0.4 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid. Endosperm liquid.

DISTRIBUTION Europe: northern, central, southwestern, southeastern, and eastern. Africa: north and Macaronesia. Asia-temperate: Soviet Middle Asia, Caucasus, and western Asia. Australasia: Australia. North America: western Canada, northwest USA, and north-central USA. South America: southern South America.

NOTES Aveneae. FW 1995.

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