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.

Anthoxanthum horsfieldii

HABIT Perennial. Rhizomes elongated. Culms 50–105 cm long. Culm-internodes hollow; distally glabrous. Lateral branches lacking, or sparse. Leaf-sheaths glabrous on surface; outer margin hairy. Ligule an eciliate membrane; 0.7–2 mm long. Leaf-blades 15–37 cm long; 5–10 mm wide; flaccid; aromatic. Leaf-blade surface glabrous; hairless throughout, or except near base. Leaf-blade margins glabrous, or ciliate.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; elliptic; continuous, or interrupted; 3.5–13.5 cm long; 0.7–2.2 cm wide. Primary panicle branches 1–3 -nate; 1.5–5.4 cm long; bearing 5–28 fertile spikelets on each lower branch. Panicle axis glabrous. Panicle branches glabrous, or pubescent.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels pubescent.

FERTILE SPIKELETS Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 4.5–7.4 mm long; 1.3–2.5 mm wide; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; dissimilar; exceeding apex of florets; thinner than fertile lemma. Lower glume ovate; 2.7–5.1 mm long; 0.5–0.9 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein eciliate, or ciliolate. Lower glume lateral veins absent. Lower glume apex obtuse, or acute. Upper glume obovate; 4.4–7.3 mm long; 1.6–2.2 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein eciliate, or ciliolate. Upper glume apex acute, or acuminate.

FLORETS Basal sterile florets dissimilar; barren; without significant palea; attached to and deciduous with the fertile. Lemma of lower sterile floret oblong; 3.7–6.4 mm long; membranous; without keels; 5 -veined; pubescent; hairy below; ciliate on margins; dentate; 2 -fid; obtuse; mucronate. Awn of lower sterile floret dorsal; arising 0.6–0.8 way up back of lemma; 0.4–2.75 mm long. Lemma of upper sterile floret oblong; 3.6–5.8 mm long; membranous; pubescent; ciliate on margins; dentate; 2 -fid; obtuse; awned. Awn of upper sterile floret dorsal; arising 0.25–0.5 way up back of lemma; geniculate; 4–9.2 mm long. Fertile lemma oblong; 2.3–3.5 mm long; cartilaginous; without keel; 5 -veined. Lemma lateral veins obscure. Lemma margins convolute; covering most of palea. Lemma apex emarginate. Palea linear; 2–3.4 mm long; 1 -veined; without keels.

FLOWER Lodicules absent. Anthers 2; 1.8–3.6 mm long. Stigmas 2; protogynous; pubescent.

FRUIT Caryopsis with adherent pericarp; lanceolate, or oblong; 1.6–2.2 mm long. Hilum punctiform.

DISTRIBUTION Asia-temperate: China and eastern Asia. Asia-tropical: India, Indo-China, Malesia, and Papuasia.

NOTES Aveneae. Veldkamp 1994.

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