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Descriptions

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

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

Thrasya parvula

HABIT Perennial; caespitose. Culms erect; 40–55 cm long. Culm-nodes glabrous. Lateral branches lacking. Leaf-sheaths keeled; glabrous on surface, or puberulous. Ligule an eciliate membrane; 2 mm long; erose. Leaf-blades 2.5–12 cm long; 1.5–2.5 mm wide. Leaf-blade surface puberulous; hairy on both sides. Leaf-blade margins glabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; arcuate; unilateral; 2–4.5 cm long. Rhachis broadly winged; 3.5 mm wide; glabrous on surface; scaberulous on margins; terminating in a barren extension; extension flattened. Spikelet packing alternately adaxial and abaxial; regular; 1 -rowed.

Spikelets pectinate; in pairs. Fertile spikelets sessile and pedicelled; 2 in the cluster. Pedicels fused to internode; united wholly; pubescent.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; acute; 1.4–1.6 mm long; 0.7 mm wide; falling entire.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume oblate; 0.3 mm long; 0.2 length of spikelet; hyaline; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex truncate. Upper glume oblate; 0.4 mm long; 0.25 length of spikelet; membranous; without keels; 1 -veined. Upper glume primary vein absent. Upper glume lateral veins absent. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of spikelet; chartaceous; sulcate; acute. Fertile lemma elliptic; 1.4–1.6 mm long; coriaceous; without keel. Lemma surface papillose. Lemma margins involute. Lemma apex acute. Palea coriaceous. Palea surface papillose.

FLOWER Lodicules 2; fleshy; truncate. Anthers 3.

DISTRIBUTION South America: Brazil.

NOTES Paniceae. Burman 1993.

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