GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Dimeria lawsonii

HABIT Annual. Culms decumbent; slender; 10–25 cm long. Culm-nodes bearded. Leaf-sheaths glabrous on surface. Ligule a ciliolate membrane; 0.5 mm long. Leaf-blades 4–8 cm long; 2–3 mm wide. Leaf-blade surface scaberulous; rough on both sides; glabrous. Leaf-blade margins cartilaginous; scaberulous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; straight, or arcuate; unilateral; 3–3.5 cm long. Rhachis narrowly winged; 0.75 mm wide; ciliate on margins. Spikelet packing crowded; regular; 2 -rowed.

Spikelets appressed; solitary. Fertile spikelets pedicelled. Pedicels reduced to a stump; flattened; ciliate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; compressed strongly; 5.5 mm long; falling entire. Spikelet callus base obtuse.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma; recurved at apex. Lower glume oblong; 4.5 mm long; 0.75–0.8 length of spikelet; coriaceous; 1-keeled. Lower glume primary vein ciliate. Lower glume apex acuminate. Upper glume elliptic; 5.5 mm long; 1 length of spikelet; coriaceous; with hyaline margins; 1-keeled; winged on keel; winged all along, or above. Upper glume primary vein ciliate. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 1 mm long.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 2–3 mm long; hyaline. Fertile lemma oblong; 2.5–3 mm long; hyaline; without keel; 1 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 8 mm long overall; with twisted column. Column of lemma awn 3.5 mm long; glabrous. Palea absent or minute.

FLOWER Anthers 2; 0.8–0.9 mm long.

DISTRIBUTION Asia-tropical: India.

NOTES Andropogoneae. Bor 1993.

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