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 aequivaginatum

HABIT Annual. Culms decumbent; 20–100 cm long; rooting from lower nodes. Culm-internodes 3.5–10.5 cm long; distally glabrous, or pilose. Culm-nodes constricted; pubescent. Leaf-sheaths 3–8.5 cm long; striately veined; glabrous on surface, or hispid; outer margin hairy. Ligule a ciliolate membrane; 0.3–0.6 mm long. Collar pubescent. Leaf-blade base broadly rounded, or cordate. Leaf-blades linear, or lanceolate; 3.5–12 cm long; 5–13 mm wide. Leaf-blade midrib conspicuous. Leaf-blade surface glabrous, or hispid. Leaf-blade margins scaberulous; tuberculate-ciliate. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; effuse; 10–15 cm long; 3–7 cm wide. Primary panicle branches ascending. Panicle axis smooth; glabrous. Panicle branches flexuous; glabrous in axils, or pubescent in axils.

Spikelets solitary, or in pairs. Fertile spikelets pedicelled. Pedicels smooth; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 1.7–2.5 mm long; 0.7 mm wide; falling entire. Rhachilla internodes elongated between glumes.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; not clasping; 0.9–1.3 mm long; 0.4–0.5 length of spikelet; membranous; without keels; 3 -veined. Lower glume lateral veins without connecting veins, or transversely connected at apex. Lower glume apex acuminate. Upper glume elliptic; 0.9 length of spikelet; membranous; without keels; 9 -veined. Upper glume lateral veins without cross-veins, or transversely connected at apex. 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; 9 -veined; acute. Palea of lower sterile floret 0.25–0.33 length of lemma. Fertile lemma elliptic; dorsally compressed; 1.6–1.9 mm long; 0.6 mm wide; indurate; without keel. Lemma surface papillose. Lemma margins involute. Lemma apex apiculate. Palea involute; indurate.

FRUIT Caryopsis with adherent pericarp; ellipsoid; light brown. Embryo 0.33 length of caryopsis. Hilum punctiform.

DISTRIBUTION South America: northern South America and Brazil.

NOTES Paniceae. Zuloaga 1994.

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