|
Note - this takes you off
of our website |
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.
Ischaemum semisagittatum
HABIT Annual. Culms decumbent; 30–60 cm long. Culm-nodes glabrous. Ligule an eciliate membrane; 3 mm long. Leaf-blade base cordate, or sagittate; without a false petiole, or with a false petiole; petiole 0–2.5 cm long. Leaf-blades lanceolate; 5–7.5 cm long; 10–16 mm wide. Leaf-blade surface glabrous, or pubescent; sparsely hairy. Leaf-blade apex acuminate.
INFLORESCENCE Inflorescence composed of racemes.
Racemes 2; paired; appressed back to back; 2.5–6.3 cm long. Rhachis fragile at the nodes; angular; ciliate on margins. Rhachis internodes inflated; 3 mm long. Rhachis internode tip transverse; cupuliform.
Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels oblong; 0.5–1 mm long; 0.25–0.33 length of internode; glabrous.
STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; laterally compressed; 3–5 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; keeled; smooth, or rugose. Companion sterile spikelet lemmas 2; enclosed by glumes; muticous.
FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 4–6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base truncate; inserted.
GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume ovate; 1 length of spikelet; coriaceous; much thinner above; 2-keeled; keeled all along; keeled laterally; 3–5 -veined. Lower glume surface smooth, or rugose. Upper glume lanceolate; coriaceous; 1-keeled. Upper glume apex obtuse.
FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret ovate; membranous; 1–3 -veined; without lateral veins, or distinctly veined; acuminate. Fertile lemma oblong; 3.5–5.5 mm long; membranous; without keel. Lemma apex lobed; 2 -fid; incised 0.5 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 13–17 mm long overall; with twisted column. Column of lemma awn glabrous.
FLOWER Anthers 3.
DISTRIBUTION Asia-tropical: India.
NOTES Andropogoneae. Blatter 1993.
Please cite this publication as detailed in How to Cite Version: 3rd February 2016.
