Ischaemum rangacharianum

HABIT Annual. Culms erect, or geniculately ascending; 20–80 cm long. Culm-nodes glabrous. Leaf-sheaths keeled; glabrous on surface, or pilose; with tubercle-based hairs. Ligule an eciliate membrane; 2–5 mm long; acute. Leaf-blade base broadly rounded, or cordate; without a false petiole, or with a false petiole. Leaf-blades lanceolate, or elliptic; 1–12 cm long; 4–12 mm wide. Leaf-blade margins undulate. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2; paired; appressed back to back; 2–6 cm long. Rhachis fragile at the nodes; angular; ciliate on margins. Rhachis internodes oblong; 3–4 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; 1–2 mm long; 0.33 length of internode; ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; laterally compressed; 4–5 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; keeled; winged on keels; 11–13 -veined; smooth, or muricate; villous. Companion sterile spikelet lemmas 2; enclosed by glumes; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 5–6 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 lanceolate, or oblong; 1 length of spikelet; coriaceous; much thinner above; 2-keeled; keeled all along; keeled laterally; wingless; 9–11 -veined. Lower glume primary vein scabrous. Lower glume lateral veins obscure. Lower glume surface flat; muricate; rough on flanks; glabrous, or pubescent; hairy above. Upper glume lanceolate, or elliptic; chartaceous; 1-keeled; 3 -veined. Upper glume lateral veins obscure. Upper glume surface tuberculate.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret lanceolate, or oblong; 4.5–5 mm long; membranous; 3–5 -veined. Fertile lemma oblong; 3–4 mm long; membranous; without keel; 3 -veined. Lemma apex lobed; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 12–18 mm long overall; with twisted column. Column of lemma awn 6–8 mm long; glabrous.

FLOWER Anthers 3; 1.5–2 mm long.

DISTRIBUTION Asia-tropical: India.

NOTES Andropogoneae. Nair 1993.

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