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 cucaense

HABIT Perennial; caespitose. Rhizomes short. Basal innovations flabellate. Culms erect, or geniculately ascending; 20–30 cm long; without nodal roots, or rooting from lower nodes. Culm-internodes 1–4 cm long. Culm-nodes constricted; brown. Lateral branches ample. Leaf-sheaths 1.2 cm long; hirsute; outer margin hairy. Ligule a ciliate membrane; 0.2 mm long. Leaf-blades conduplicate; 1.5–5.5 cm long; 1–2 mm wide. Leaf-blade surface glabrous; hairless except near base. Leaf-blade margins scabrous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle; terminal and axillary. Peduncle 3–6 cm long; glabrous.

Panicle open; ovate; 2–3.5 cm long; 1.5–3.5 cm wide; bearing few spikelets. Panicle axis glabrous. Panicle branches glabrous; pubescent in axils.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 1–6 mm long; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 2.2–2.7 mm long; 0.8–0.9 mm wide; falling entire. Rhachilla internodes elongated between glumes.

GLUMES Glumes similar; reaching apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 1.5–1.9 mm long; 0.66–0.75 length of spikelet; membranous; without keels; 1(–3) -veined. Lower glume lateral veins absent, or obscure. Lower glume apex acuminate. Upper glume elliptic; 1 length of spikelet; membranous; without keels; 7–9 -veined. 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; 7–9 -veined; acute. Palea of lower sterile floret 0.75 length of lemma. Fertile lemma elliptic; dorsally compressed; 2.1–2.3 mm long; 0.7–0.8 mm wide; indurate; without keel. Lemma surface papillose. Lemma margins involute. Lemma apex apiculate; scabrous. Palea involute; indurate.

FLOWER Anthers 3; 1.2 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 1.4 mm long; light brown. Embryo 0.5 length of caryopsis. Hilum elliptic.

DISTRIBUTION South America: Brazil.

NOTES Paniceae. Zuloaga 1994.

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