GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Aegilops bicornis

HABIT Annual; caespitose. Culms geniculately ascending; 15–45 cm long. Leaf-sheath oral hairs ciliate. Leaf-sheath auricles falcate. Ligule an eciliate membrane. Leaf-blades flat, or involute; 5–10 cm long; 2–2.5 mm wide. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; linear; bilateral; 5–8 cm long; bearing 12–16 fertile spikelets on each. Rhachis fragile at the nodes. Spikelet packing broadside to rhachis. Rhachis internodes oblong; 0.5 length of fertile spikelet; falling with spikelet above.

Spikelets solitary. Fertile spikelets sessile.

STERILE SPIKELETS Basal sterile spikelets rudimentary; 1 in number.

FERTILE SPIKELETS Spikelets comprising 1–2 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 5.5–8.5 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes similar; shorter than spikelet. Lower glume oblong; 5–7 mm long; 1 length of upper glume; coriaceous; without keels; 4–6 -veined. Lower glume lateral veins distinct; ribbed. Lower glume apex with a unilateral tooth, or dentate; 1–2 -fid. Upper glume oblong; 5–7 mm long; 1.2 length of adjacent fertile lemma; coriaceous; without keels; 4–6 -veined. Upper glume lateral veins distinct; ribbed; parallel at apex. Upper glume apex with a unilateral tooth, or dentate; 1–2 -fid.

FLORETS Fertile lemma elliptic; 4–6 mm long; coriaceous; keeled; keeled above; 5 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn 30–60 mm long overall. Palea 2 -veined. Palea keels scaberulous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; hairy at apex. Disseminule comprising a rhachis internode.

DISTRIBUTION Africa: north. Asia-temperate: western Asia and Arabia.

NOTES Triticeae. Eig 1993.

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