Ischaemum quilonense

HABIT Perennial; caespitose. Culms decumbent; 40–80 cm long; rooting from lower nodes. Culm-internodes smooth. Culm-nodes glabrous. Leaves cauline. Leaf-sheaths 6–12 cm long; glabrous on surface. Ligule an eciliate membrane; 5 mm long. Leaf-blade base cuneate; without a false petiole, or with a false petiole; petiole 1–3.5 cm long. Leaf-blades linear, or lanceolate; 10–20 cm long; 5–10 mm wide. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2; paired; appressed back to back; 5–10 cm long. Rhachis fragile at the nodes; angular. Rhachis internodes columnar; flat and forming a U or V shape with the pedicel in rear view. Rhachis internode tip transverse; cupuliform.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels columnar; angular; 1.5–2 mm long; bearing a few hairs, or ciliate; hairy on one margin.

STERILE SPIKELETS Companion sterile spikelets well-developed; bisexual; elliptic, or oblong; 4.5–6 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; without keels; winged on keels; 11–13 -veined; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes; 4–5 mm long; muticous, or 1-awned; with 0–4 mm long awn.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong, or ovate; dorsally compressed; 5–7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus square; 0.75 mm long; glabrous, or pubescent; base truncate; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; coriaceous; much thinner above; 2-keeled; keeled all along; keeled laterally; winged on keel; winged narrowly; 11–13 -veined. Lower glume surface convex; muricate; rough on flanks. Lower glume apex emarginate, or truncate. Upper glume elliptic; 5–6 mm long; coriaceous; much thinner above; 1-keeled; keeled above; winged on keel; winged near apex; 3–5 -veined. Upper glume primary vein scaberulous. Upper glume surface asperulous.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret lanceolate; 5–5.5 mm long; membranous; scaberulous. Fertile lemma elliptic; 4.5–5 mm long; membranous; without keel; 3–5 -veined. Lemma apex lobed; 2 -fid; muticous, or awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 5–10 mm long overall; with a straight or slightly twisted column. Column of lemma awn 3–5 mm long; glabrous.

FLOWER Lodicules 2; 1 mm long. Anthers 3; 2.5–3 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid, or oblong; 3 mm long.

DISTRIBUTION Asia-tropical: India.

NOTES Andropogoneae. Fl Kerala 2006.

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