Psathyrostachys caduca

HABIT Perennial; caespitose. Butt sheaths light brown; glabrous. Culms 23–45 cm long; 3–4 -noded. Culm-internodes distally glabrous, or pubescent. Culm-nodes brown; glabrous. Leaf-sheaths pubescent. Ligule an eciliate membrane. Leaf-blades 17–170 cm long; 2–5 mm wide. Leaf-blade surface ribbed; pubescent; densely hairy; hairy on both sides. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence composed of racemes. Peduncle pubescent above.

Racemes 1; single; linear, or oblong; bilateral; 3–7.6 cm long; 7–12 mm wide. Rhachis fragile at the nodes; ciliate on margins. Spikelet packing broadside to rhachis. Rhachis internodes cuneate; 2.7–3.9 mm long; falling with spikelet above.

Spikelets in threes. Fertile spikelets sessile; 3 in the cluster; subequal.

FERTILE SPIKELETS Spikelets comprising 1(–2) fertile florets; with a barren rhachilla extension. Spikelets lanceolate; dorsally compressed; 15–28 mm long; 1.2–2 mm wide; falling entire; deciduous with accessory branch structures.

GLUMES Glumes collateral; similar; exceeding apex of florets; gaping. Lower glume subulate; 15–28 mm long; 1 length of upper glume. Lower glume surface pilose. Lower glume hairs 0.7–1 mm long. Upper glume subulate; 15–28 mm long. Upper glume surface pilose. Upper glume hairs 0.7–1 mm long.

FLORETS Fertile lemma lanceolate; 7.5–19 mm long; coriaceous; without keel; 7 -veined. Lemma midvein scabrous. Lemma surface glabrous. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 6–14 mm long overall; limb scabrous. Palea coriaceous. Palea surface pubescent. Rhachilla extension 2–4.4 mm long.

FLOWER Anthers 5.5–6.8 mm long; purple. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; 6.5–7.5 mm long. Hilum linear.

DISTRIBUTION Asia-temperate: western Asia.

NOTES Triticeae. Baden 1992.

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