Lolium rigidum

HABIT Annual. Culms erect, or geniculately ascending, or decumbent; 18–43 cm long; 2–4 -noded. Leaf-sheaths smooth, or scaberulous. Leaf-sheath oral hairs lacking. Leaf-sheath auricles absent, or falcate. Ligule an eciliate membrane; 1–1.5 mm long; truncate, or obtuse. Leaf-blades 5–17 cm long; 0.5–5 mm wide. Leaf-blade surface smooth, or scaberulous; rough adaxially. Leaf-blade margins smooth, or scaberulous. Leaf-blade apex acute to attenuate.

INFLORESCENCE Inflorescence composed of racemes. Peduncle smooth, or scaberulous above.

Racemes 1; single; straight, or arcuate; bilateral; 3–30 cm long; bearing 2–19 fertile spikelets on each. Rhachis subcylindrical and excavated; 1–2.5 mm wide; smooth on surface, or scabrous on surface. Spikelet packing adaxial; regular; 2 -rowed.

Spikelets sunken, or appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 2–8 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 5–18 mm long; 1–3 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.9–2.8 mm long (0.25–0.5 length of lemma).

GLUMES Glumes one the lower absent or obscure; persistent; shorter than spikelet, or reaching apex of florets; similar to fertile lemma in texture. Upper glume lanceolate, or oblong; 4–20 mm long; 0.75–1 length of spikelet; coriaceous; without keels; 3–7 -veined. Upper glume surface smooth, or asperulous. Upper glume apex obtuse, or acute.

FLORETS Fertile lemma lanceolate; 3.2–8.5 mm long; coriaceous; without keel; 3–5 -veined. Lemma surface smooth, or scaberulous. Lemma apex entire, or erose; obtuse, or acute; muticous, or awned (rarely); 1 -awned. Principal lemma awn subapical; 0–3(–10) mm long overall. Palea keels scaberulous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; lanceolate; 0.8–1 mm long; membranous. Anthers 3; 1.2–3.1 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; fusiform; 2.7–5.5 mm long. Hilum linear.

DISTRIBUTION Europe: central, southwestern, southeastern, and eastern. Africa: north, Macaronesia, west tropical, and south. Asia-temperate: Soviet far east, Soviet Middle Asia, Caucasus, western Asia, Arabia, China, and eastern Asia. Asia-tropical: India. Australasia: Australia and New Zealand. South America: southern South America. Antarctic: Subantarctic islands.

NOTES Poeae. Terrell.

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