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.

Panicum pantrichum

HABIT Perennial; mat forming. Culms rambling; 6–25 cm long; 1 mm diam.; rooting from lower nodes. Culm-internodes distally pubescent. Lateral branches lacking. Leaf-sheaths pilose; with tubercle-based hairs. Ligule a ciliolate membrane; 0.2–0.3 mm long. Leaf-blade base asymmetrical. Leaf-blades ovate; 3.5–8 cm long; 7–10 mm wide. Leaf-blade surface pubescent.

INFLORESCENCE Inflorescence a panicle; terminal and axillary. Axillary inflorescences present in upper axils; enclosed.

Panicle open; pyramidal; 2–10 cm long; 1–8 cm wide; bearing few spikelets; contracted about primary branches.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; acute; 2.2–2.8 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 1.6–2.3 mm long; 0.75 length of spikelet; membranous; without keels; 3 -veined. Lower glume surface pubescent. Lower glume apex obtuse. Upper glume ovate; 2.2–2.7 mm long; 1 length of spikelet; membranous; without keels; 5–7 -veined. Upper glume surface pubescent. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; ovate; 2–2.5 mm long; 1 length of spikelet; membranous; 5–6 -veined; without midvein, or with obscure midvein; pubescent; acute. Fertile lemma elliptic, or obovate; dorsally compressed; 1.9–2.2 mm long; indurate; shiny; without keel. Lemma margins involute. Palea involute; indurate.

FLOWER Anthers 3; 0.3 mm long; retained within floret; pallid.

FRUIT Caryopsis ellipsoid; 0.9–1.4 mm long; light brown, or red.

DISTRIBUTION South America: Mesoamericana, northern South America, western South America, Brazil, and southern South America.

NOTES Paniceae. Fl Costa Rica 1994.

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