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.

Rhizocephalus orientalis

HABIT Annual; caespitose. Butt sheaths scarious. Culms 0.5–2 cm long. Leaf-sheaths inflated. Ligule an eciliate membrane; 0.5–1 mm long; lacerate. Leaf-blades 0.8–4 cm long; 1–4 mm wide. Leaf-blade surface scaberulous; rough adaxially. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle; shorter than basal leaves; subtended by an inflated leaf-sheath; embraced at base by subtending leaf.

Panicle capitate; oblong, or ovate; 0.8–1.5 cm long; 0.4–0.8 cm wide. Primary panicle branches accrescent to a central axis; with lateral stumps on axis. Panicle axis angular; glabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels oblong.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 3.5–6.5 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes connate along margins below (slightly); persistent; similar; shorter than spikelet. Lower glume obovate; 2.5–4 mm long; 1 length of upper glume; coriaceous; 1-keeled; 3 -veined. Lower glume surface pubescent; with clavate hairs. Lower glume apex cuspidate. Upper glume obovate; 2.5–4 mm long; 0.6–0.7 length of adjacent fertile lemma; coriaceous; 1-keeled; 3 -veined. Upper glume surface pubescent; with clavate hairs. Upper glume apex cuspidate.

FLORETS Fertile lemma oblong; 3.5–6.5 mm long; coriaceous; much thinner on margins; keeled; 5 -veined. Lemma surface scaberulous; rough on veins; pubescent; hairy below; with clavate hairs. Lemma apex attenuate; awned; 1 -awned. Principal lemma awn 0.5–1 mm long overall; limb scaberulous. Palea lanceolate; 0.8 length of lemma; 2 -veined.

FLOWER Lodicules absent. Anthers 2; 0.5–0.7 mm long. Stigmas protogynous. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; ellipsoid; trigonous; apex rostrate. Embryo 0.25–0.33 length of caryopsis. Hilum punctiform.

DISTRIBUTION Asia-temperate: Soviet Middle Asia, Caucasus, and western Asia.

NOTES Aveneae. Fl Turk.

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