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 itatiaiae

HABIT Perennial. Culms decumbent; 90–120 cm long; rooting from lower nodes. Culm-internodes 3–14 cm long; distally glabrous. Culm-nodes purple; glabrous. Lateral branches ample; arising from upper culm. Leaf-sheaths 3–8 cm long; glabrous on surface; outer margin hairy. Ligule a ciliate membrane; 0.3–0.4 mm long. Collar pubescent. Leaf-blade base broadly rounded. Leaf-blades lanceolate, or oblong; 10–12 cm long; 10–14 mm wide. Leaf-blade midrib conspicuous. Leaf-blade surface glabrous; hairless except near base. Leaf-blade margins scabrous; ciliate.

INFLORESCENCE Inflorescence a panicle. Peduncle 20–40 cm long; scaberulous above.

Panicle open; ovate; effuse; 13–18 cm long; 10–20 cm wide. Panicle axis glabrous. Panicle branches scabrous; glabrous in axils.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 3–8 mm long; smooth.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 4.6–5 mm long; 1.6–1.7 mm wide; falling entire. Rhachilla internodes elongated between glumes.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 2.6–3.2 mm long; 0.5–0.6 length of spikelet; membranous; without keels; 5 -veined. Lower glume apex acuminate. Upper glume elliptic; 4–4.3 mm long; 0.9 length of spikelet; membranous; without keels; (11–)13 -veined. Upper glume surface asperulous. Upper glume apex obtuse.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; 13 -veined; scaberulous; acute. Palea of lower sterile floret 1 length of lemma; pilose; adorned on flanks. Fertile lemma lanceolate; dorsally compressed; 4–4.2 mm long; 1.3–1.6 mm wide; indurate; without keel; 7 -veined. Lemma surface scaberulous; rough above. Lemma margins involute. Lemma apex apiculate; pubescent. Palea involute; indurate. Palea surface scaberulous (above).

FLOWER Anthers 3; 2.2 mm long.

FRUIT Caryopsis with adherent pericarp; obovoid; 2.5 mm long. Embryo 0.2 length of caryopsis. Hilum punctiform.

DISTRIBUTION South America: Brazil.

NOTES Paniceae. Zuloaga 1994.

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