Ischaemum lanatum

HABIT Annual. Culms erect, or geniculately ascending, or decumbent; slender; 50–100 cm long; rooting from lower nodes. Culm-nodes pubescent. Leaf-sheaths 5–9 cm long; keeled; striately veined; pilose; with tubercle-based hairs; outer margin hairy. Ligule an eciliate membrane; 3–5 mm long; pubescent on abaxial surface; truncate. Leaf-blade base broadly rounded, or cordate; with a false petiole; petiole 0.5–1 cm long. Leaf-blades lanceolate; 5–10 cm long; 5–10 mm wide. Leaf-blade surface scaberulous; rough on both sides; glabrous, or pilose; sparsely hairy; hairy on both sides. Leaf-blade margins scaberulous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2; paired; appressed back to back; 4–7 cm long. Rhachis fragile at the nodes; angular; woolly on surface. Rhachis hairs 2.5 mm long. Rhachis internodes clavate; 4–6.5 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; 1.5–2.5 mm long; 0.4 length of internode; villous.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; laterally compressed; 4.5–6.5 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; keeled; 7–11 -veined; villous. Companion sterile spikelet lemmas 2; enclosed by glumes; 4.25–4.75 mm long; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or elliptic; dorsally compressed; 5–5.5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus oblong; 1–2 mm long; pilose; base truncate; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate, or elliptic; 1 length of spikelet; coriaceous; much thinner above; 2-keeled; keeled all along; keeled laterally; 9–11 -veined. Lower glume primary vein scaberulous. Lower glume surface smooth, or rugose; woolly. Lower glume hairs 2–3 mm long. Upper glume lanceolate, or oblong; coriaceous; 1-keeled; 5–7 -veined. Upper glume surface villous. Upper glume apex acuminate.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret ovate; 4.5–5.5 mm long; hyaline; acuminate. Palea of lower sterile floret 4.25–5.5 mm long. Fertile lemma elliptic; 3.75–5 mm long; hyaline; without keel; 3 -veined. Lemma margins ciliolate. Lemma apex lobed; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 13–19 mm long overall; with twisted column. Column of lemma awn 5–8 mm long; glabrous. Palea 3.5–4.5 mm long.

FLOWER Lodicules 2; 0.75–1 mm long. Anthers 3; 3 mm long.

FRUIT Caryopsis with adherent pericarp; obovoid; 1.8 mm long.

DISTRIBUTION Asia-tropical: India.

NOTES Andropogoneae. Ravi et al 2006.

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