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 mystasipum

HABIT Perennial; caespitose. Butt sheaths persistent and investing base of culm; with compacted dead sheaths. Culms erect; 45–106 cm long. Culm-internodes terete; striate; distally glabrous. Culm-nodes glabrous. Leaf-sheaths 6–14 cm long; longer than adjacent culm internode; hirsute; outer margin hairy. Ligule a ciliate membrane; 0.8–1.2 mm long. Leaf-blades involute; 20–45 cm long; 3–5 mm wide; stiff. Leaf-blade surface scaberulous; rough abaxially; pilose; sparsely hairy; hairy adaxially. Leaf-blade margins scabrous; ciliate; hairy at base. Leaf-blade apex attenuate; muticous, or pungent.

INFLORESCENCE Inflorescence a panicle; comprising 10–20 fertile spikelets. Peduncle 30–70 cm long; glabrous.

Panicle open; ovate; 9–20 cm long; 1–6 cm wide; bearing few spikelets. Primary panicle branches appressed, or ascending; simple; 6–12 cm long. Panicle axis scabrous; glabrous, or hispid. Panicle branches glabrous in axils, or bearded in axils.

Spikelets appressed; solitary. Fertile spikelets pedicelled. Pedicels scabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 7.2–9.2 mm long; 2–2.4 mm wide; falling entire. Spikelet callus square; 0.5 mm long. Rhachilla internodes elongated between glumes.

GLUMES Glumes similar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 4.5–5.8 mm long; 0.5–0.75 length of spikelet; membranous; without keels; 7–9 -veined. Lower glume primary vein scabrous. Lower glume apex acute. Upper glume ovate; 6.8–8 mm long; 1 length of spikelet; membranous; without keels; 9–11 -veined. Upper glume primary vein scabrous. Upper glume apex acuminate.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 6–7.2 mm long; 1 length of spikelet; membranous; 7–9 -veined; acute. Palea of lower sterile floret 4.8–5.2 mm long; pilose; adorned on flanks. Fertile lemma elliptic; dorsally compressed; 4.8 mm long; 1.6 mm wide; indurate; yellow and black; suffused with last colour; without keel; 7 -veined. Lemma margins involute; ciliate; hairy at base. Palea involute; indurate.

FLOWER Anthers 3; 3 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 3.5 mm long. Embryo 0.5 length of caryopsis. Hilum punctiform.

DISTRIBUTION South America: Brazil.

NOTES Paniceae. Zuloaga 1996.

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