Trilobachne cookei

HABIT Annual. Culms 100–250 cm long. Culm-nodes pubescent. Ligule an eciliate membrane. Leaf-blades lanceolate; 20–50 cm long; 20–60 mm wide. Leaf-blade surface pilose; with tubercle-based hairs. Leaf-blade margins scabrous.

INFLORESCENCE Monoecious; with male and female spikelets in the same inflorescence, or with male and female spikelets in different inflorescences. Inflorescence composed of racemes; axillary; subtended by a spatheole; embraced at base by subtending leaf. Spatheole lanceolate; herbaceous.

Racemes 1; single; 2–3 cm long; bearing few fertile spikelets; bearing 1–4 fertile spikelets on each (and 4–6 male spikelets). Rhachis fragile at the nodes; subterete; pilose on surface. Rhachis internodes oblong; bearing a sterile companion laterally. Rhachis internode tip cupuliform.

Sexes segregated; on bisexual branches; with male above. Spikelets embracing internode; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Male spikelets sessile and pedicelled; 2 in a cluster. Pedicels fused to internode; united wholly.

STERILE SPIKELETS Companion sterile spikelets well-developed; comprising 2 unequal glumes without lemmas; lanceolate; 4–6 mm long; as long as fertile; separately deciduous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 6–7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base truncate; with central peg; attached transversely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; indurate; much thinner above; pallid; without keels; winged on margins; winged above. Lower glume surface not waisted; pubescent. Lower glume apex lobed; 3 -fid; obtuse. Upper glume elliptic; coriaceous. Upper glume apex acuminate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; cartilaginous; acute. Fertile florets female. Fertile lemma oblong; hyaline; without keel. Lemma apex acute. Palea hyaline; without keels.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

MALE Male inflorescence of subdigitate racemes. Male spikelets distinct from female; with free pedicels; 4 mm long. Male spikelet glumes 2.

DISTRIBUTION Asia-tropical: India.

NOTES Andropogoneae. WDC.

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