GrassBase - The Online World Grass Flora


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

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

Psathyrostachys lanuginosa

HABIT Perennial; caespitose. Butt sheaths grey, or light brown; glabrous. Culms 15–60 cm long; 2–3 -noded. Culm-internodes distally glabrous. Leaf-sheath oral hairs lacking. Leaf-sheath auricles absent, or falcate. Ligule an eciliate membrane; 0.2–0.6 mm long. Leaf-blades flat, or involute; 4–13 cm long; 3–4 mm wide; glaucous. Leaf-blade surface scabrous; rough adaxially, or on both sides; glabrous. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence composed of racemes. Peduncle glabrous, or pubescent above.

Racemes 1; single; oblong; bilateral; 1–3 cm long; 4–9 mm wide. Rhachis fragile at the nodes; ciliate on margins. Spikelet packing broadside to rhachis. Rhachis internodes cuneate; 1.5–3 mm long; falling with spikelet above.

Spikelets in pairs (rarely), or in threes. Fertile spikelets sessile; (2–)3 in the cluster; subequal.

FERTILE SPIKELETS Spikelets comprising 1(–2) fertile florets; with a barren rhachilla extension. Spikelets lanceolate; dorsally compressed; 5.5–10.5 mm long; 1.1–1.7 mm wide; falling entire; deciduous with accessory branch structures.

GLUMES Glumes collateral; similar; exceeding apex of florets; gaping. Lower glume subulate; 5.5–10.5 mm long; 1 length of upper glume. Lower glume surface villous. Lower glume hairs 0.5–1.3 mm long. Upper glume subulate; 5.5–10.5 mm long. Upper glume surface villous. Upper glume hairs 0.5–1.3 mm long.

FLORETS Fertile lemma lanceolate; 5.8–9 mm long; coriaceous; without keel; 7 -veined. Lemma surface pilose. Lemma hairs 0.7–1 mm long. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 1.3–2.5(–3.7) mm long overall; limb ciliate. Palea coriaceous. Palea surface pilose. Rhachilla extension 2.7–5.5 mm long.

FLOWER Anthers 3–4 mm long; yellow. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; 3.5–3.8 mm long. Hilum linear.

DISTRIBUTION Asia-temperate: Siberia, Soviet Middle Asia, western Asia, and China.

NOTES Triticeae. Baden 1992.

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