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.

Paspalum petrosum

HABIT Perennial; caespitose. Butt sheaths pubescent (tomentose). Culms erect; 70–85 cm long. Culm-internodes distally glabrous. Leaf-sheaths pilose. Ligule an eciliate membrane. Leaf-blades curved; involute; 15–35 cm long. Leaf-blade surface pubescent; hairy adaxially.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 5–8; borne along a central axis; unilateral; 4–5 cm long. Central inflorescence axis 4–8 cm long. Rhachis narrowly winged; angular; 0.4–0.5 mm wide; glabrous on surface.

Spikelets solitary, or in pairs. Fertile spikelets pedicelled. Pedicels oblong; 0.5 mm long; pubescent.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets obovate; dorsally compressed; plano-convex; subacute; 1.8–1.9 mm long; falling entire.

GLUMES Glumes one the lower absent or obscure; reaching apex of florets; thinner than fertile lemma. Upper glume elliptic; 1 length of spikelet; membranous; without keels; 5 -veined. Upper glume primary vein conspicuous. Upper glume surface glabrous. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of spikelet; membranous; 5 -veined; with conspicuous midvein; glabrous; acute. Fertile lemma elliptic; 1.8–1.9 mm long; indurate; shiny; without keel. Lemma surface smooth. Lemma margins involute. Palea involute; indurate.

DISTRIBUTION South America: western South America.

NOTES Paniceae. Swallen 2004.

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