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.

Piptochaetium calvescens

HABIT Perennial; caespitose. Culms erect; 30–40 cm long; 3 -noded. Leaf-sheaths mostly shorter than adjacent culm internode; smooth; glabrous on surface. Ligule an eciliate membrane; 1.5 mm long; 0.5 mm long on basal shoots. Leaf-blades filiform; conduplicate; 5–10 cm long; 0.5 mm wide. Leaf-blade venation with 3 secondary veins. Leaf-blade surface ribbed; grooved adaxially; scabrous; rough adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear, or oblong; 5–7 cm long; 1 cm wide. Primary panicle branches appressed. Panicle axis glabrous, or puberulous. Panicle branches puberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels puberulous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 5–6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus brief; glabrous, or sparsely hairy; obtuse.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 5–6 mm long; 1.2 length of upper glume; membranous; much thinner on margins; purple; without keels; 5 -veined. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 0.5–1 mm long. Upper glume lanceolate; 4–4.5 mm long; membranous; with hyaline margins; purple; without keels; 3 -veined. Upper glume apex acute; awned; 1 -awned. Upper glume awn 0.5–1 mm long.

FLORETS Fertile lemma obovate; laterally compressed; gibbous; 3 mm long; indurate; without keel. Lemma surface tuberculate; rough generally. Lemma margins involute; interlocking with palea keels. Lemma apex with an annular corona; awned; 1 -awned. Principal lemma awn eccentric; bigeniculate; 12–14 mm long overall; with twisted column; deciduous. Palea reflexed at apex; 1 length of lemma; 2 -veined. Palea keels contiguous above a sulcus.

FLOWER Anthers 3; 0.25 mm long; retained within floret.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: southern South America.

NOTES Stipeae. Parodi 1997.

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