GrassBase - The Online World Grass Flora

Descriptions

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

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

Mesosetum wrightii

HABIT Perennial. Stolons present. Culms decumbent; 10–40 cm long; rooting from lower nodes. Culm-nodes bearded. Leaves mostly basal. Leaf-sheaths striately veined; glabrous on surface, or pilose; outer margin hairy. Ligule a fringe of hairs; 1 mm long. Leaf-blades linear, or lanceolate; 2–6.5 cm long; 2–4 mm wide. Leaf-blade surface glabrous, or pilose; with tubercle-based hairs. Leaf-blade margins cartilaginous; glabrous, or tuberculate-ciliate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; unilateral; 1.5–3 cm long. Rhachis angular; 0.5 mm wide; pubescent on margins. Spikelet packing adaxial; regular; 2 -rowed.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels oblong; 1 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 3.2–4.2 mm long; falling entire. Spikelet callus pubescent.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume lanceolate; 2–2.5 mm long; 0.6 length of spikelet; chartaceous; much thinner on margins; 1-keeled; 3 -veined. Lower glume surface glabrous, or pilose. Lower glume apex dentate; 2 -fid. Upper glume lanceolate; 3.5–3.8 mm long; 1 length of spikelet; membranous; without keels; 7–9 -veined. Upper glume lateral veins transversely connected at apex. Upper glume surface glabrous, or pilose; with a dorsal tuft of hair. Upper glume margins ciliate. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 1 length of spikelet; membranous; 7 -veined; with veins transversely connected at apex; with marginal tufts of hair and with dorsal tufts of hair; 3 hair tufts in all; ciliolate on margins; acute. Fertile lemma ovate; dorsally compressed; 2.5–2.8 mm long; coriaceous; shiny; without keel; 5 -veined. Lemma lateral veins obscure. Lemma surface smooth. Lemma margins flat; covering most of palea. Lemma apex acute. Palea coriaceous; without keels.

FLOWER Anthers 3; purple.

FRUIT Caryopsis 2 mm long; dark brown. Embryo 0.5 length of caryopsis. Hilum linear; 0.66 length of caryopsis.

DISTRIBUTION South America: Caribbean.

NOTES Paniceae. Filgueiras.

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