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 dalzellii

HABIT Annual. Culms geniculately ascending, or decumbent; 30–50 cm long. Ligule an eciliate membrane; 4 mm long; pilose on abaxial surface. Leaf-blade base with a false petiole; petiole 1–5 cm long. Leaf-blades 3–7 cm long; 7–14 mm wide. Leaf-blade surface pilose; hairy on both sides; with tubercle-based hairs. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2; paired; 2–3 cm long. Rhachis fragile at the nodes; semiterete; ciliate on margins. Rhachis internodes clavate; 3.5 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 mm long; 0.1 length of fertile spikelet; ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; oblong; laterally compressed; 5 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; keeled. Companion sterile spikelet lemmas 2; enclosed by glumes; entire; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 5–5.5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus square; 1 mm long; pilose; base truncate; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; coriaceous; 2-keeled; keeled all along; keeled laterally; winged on keel; winged narrowly; winged above; 3 -veined. Lower glume primary vein scabrous. Lower glume surface convex, or flat; pilose. Lower glume apex obtuse. Upper glume lanceolate; coriaceous; much thinner above; 1-keeled; 3 -veined. Upper glume surface scabrous.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret lanceolate; 4.5 mm long; hyaline; 3 -veined. Fertile lemma oblong; 3 mm long; hyaline; without keel; 3 -veined. Lemma margins ciliate; hairy above. Lemma apex lobed; 2 -fid; incised 0.5 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 14 mm long overall; with twisted column. Column of lemma awn 7 mm long; glabrous. Palea 1 length of lemma.

FLOWER Anthers 3; 2.5–4 mm long.

DISTRIBUTION Asia-tropical: India.

NOTES Andropogoneae. Bor 1993.

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