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 aquarum

HABIT Annual. Culms erect; 90–130 cm long; rooting from lower nodes. Culm-internodes hollow; 7–19 cm long; distally glabrous. Culm-nodes brown; glabrous. Lateral branches ample; arising from upper culm. Leaf-sheaths 8–18 cm long. Ligule a ciliate membrane; 1.2 mm long; pilose on abaxial surface. Collar glabrous. Leaf-blades persistent, or deciduous at the ligule; involute; 11–18 cm long; 2–4 mm wide. Leaf-blade surface scaberulous.

INFLORESCENCE Inflorescence a panicle; terminal and axillary. Peduncle 10–25 cm long; scaberulous above; glabrous.

Panicle open; pyramidal; 35–40 cm long; 12–28 cm wide. Panicle branches scaberulous; glabrous in axils.

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

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 3–3.9 mm long; 1–1.2 mm wide; falling entire. Rhachilla internodes elongated between glumes.

GLUMES Glumes reaching apex of florets; thinner than fertile lemma; gaping. Lower glume ovate; 1.7–2.7 mm long; 0.5–0.75 length of spikelet; membranous; without keels; 5 -veined. Lower glume primary vein scaberulous. Lower glume apex acuminate. Upper glume ovate; 1 length of spikelet; membranous; without keels; 7 -veined. Upper glume apex acuminate.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 1 length of spikelet; membranous; 7 -veined; acute. Palea of lower sterile floret 1.7–2.1 mm long; 0.5–0.66 length of lemma. Fertile lemma elliptic; dorsally compressed; 2.1 mm long; indurate; yellow and black; mottled with last colour; shiny; without keel; 5 -veined. Lemma margins involute. Palea involute; indurate. Palea apex papillose.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 1.5 mm long. Embryo 0.33 length of caryopsis. Hilum punctiform.

DISTRIBUTION South America: northern South America.

NOTES Paniceae. Zuloaga 1995.

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