GrassBase - The Online World Grass Flora


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

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

Panicum davidsei

HABIT Perennial. Culms decumbent; 150–320 cm long; rooting from lower nodes. Culm-internodes 8–23 cm long; distally hispid. Culm-nodes constricted; bearded. Lateral branches ample; arising from lower culm. Leaf-sheaths 5–8 cm long; hirsute; with tubercle-based hairs; outer margin hairy. Ligule a ciliate membrane; 0.2 mm long. Collar pilose. Leaf-blade base broadly rounded. Leaf-blades lanceolate; 9–13 cm long; 10–13 mm wide. Leaf-blade midrib conspicuous. Leaf-blade surface pilose; sparsely hairy; hairy abaxially. Leaf-blade margins glabrous, or ciliate; hairy at base. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle. Peduncle 10–40 cm long.

Panicle open; ovate; 12–20 cm long; 7–12 cm wide. Primary panicle branches whorled at lower nodes. Panicle branches flexuous; eglandular; glabrous; pubescent in axils.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels flexuous; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; with a barren rhachilla extension. Spikelets elliptic; dorsally compressed; 3–3.3 mm long; 1 mm wide; falling entire. Rhachilla internodes elongated between glumes.

GLUMES Glumes similar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 1.3–1.8 mm long; 0.5 length of spikelet; membranous; without keels; 3 -veined. Lower glume surface asperulous. Lower glume apex acuminate. Upper glume elliptic; 2.1–2.7 mm long; 0.66–0.75 length of spikelet; membranous; without keels; 11–14 -veined. Upper glume surface asperulous. Upper glume apex acute.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; 10–12 -veined; acute. Palea of lower sterile floret 2.1–2.4 mm long; 0.66 length of lemma. Fertile lemma elliptic; dorsally compressed; 2.4–2.7 mm long; 1 mm wide; indurate; without keel; winged on margins (at apex). Lemma surface papillose. Lemma margins involute. Lemma apex acute; with a little green crest and scabrous. Palea involute; indurate.

FLOWER Anthers 3; 1.2 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 1.8 mm long. Embryo 0.33 length of caryopsis. Hilum punctiform.

DISTRIBUTION South America: northern South America.

NOTES Paniceae. Zuloaga 1994.

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