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 pyrularium

HABIT Annual. Culms decumbent; 5–30 cm long; rooting from lower nodes. Culm-internodes distally glabrous. Culm-nodes glabrous, or bearded. Lateral branches lacking, or ample; arising from lower culm. Leaf-sheaths mostly shorter than adjacent culm internode; glabrous on surface, or pilose; with tubercle-based hairs; outer margin hairy. Ligule an eciliate membrane; 0.3–0.6 mm long; erose. Leaf-blade base cordate. Leaf-blades lanceolate, or elliptic; 25–37 cm long; 4–9 mm wide. Leaf-blade surface glabrous, or pilose; sparsely hairy, or moderately hairy, or densely hairy; with tubercle-based hairs. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle; terminal and axillary. Peduncle 2–12 cm long.

Panicle open, or contracted; lanceolate, or ovate; 2–10 cm long. Panicle branches glabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; 5–14 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets obovate; dorsally compressed; 1.2–1.8 mm long; 0.5 mm wide; falling entire; deciduous from the base, or with the pedicel. Rhachilla internodes elongated between glumes. Rhachilla elongation 0.25 mm long.

GLUMES Glumes reaching apex of florets; thinner than fertile lemma. Lower glume lanceolate; 0.7–1.4 mm long; 0.6–0.75 length of spikelet; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1 length of spikelet; membranous; without keels; 5 -veined. Upper glume surface glabrous, or pubescent. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; ovate; 1 length of spikelet; membranous; 3 -veined; glabrous, or pubescent; acute. Fertile lemma elliptic; dorsally compressed; 1–1.3 mm long; indurate; pallid; without keel. Lemma surface smooth. Lemma margins involute. Lemma apex acute. Palea involute; indurate.

FLOWER Anthers 3; 0.6 mm long; purple.

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

NOTES Paniceae. Fl Guiana 1995.

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