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.

Otachyrium succisum

HABIT Annual. Culms erect; (10–)45–60(–85) cm long; 3–8 mm diam.; without nodal roots. Lateral branches lacking, or sparse. Leaves basal and cauline. Leaf-sheaths pilose. Ligule an eciliate membrane; 0.5 mm long; erose; truncate. Leaf-blades linear, or lanceolate; (2–)10–30 cm long; 5–15 mm wide. Leaf-blade surface glabrous, or pilose; with tubercle-based hairs. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 5–30 cm long; 5–10 cm wide. Panicle branches capillary.

Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels unequal; 1–5 mm long, or 10–20 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; laterally compressed; 2.2–2.5 mm long; falling entire.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.25 length of spikelet; membranous; without keels; 1–3 -veined. Lower glume apex obtuse. Upper glume orbicular; 0.33 length of adjacent fertile lemma; membranous; without keels; 5–7 -veined. Upper glume apex truncate.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret ovate; 1 length of spikelet; coriaceous; 3 -veined; sulcate; acute. Palea of lower sterile floret becoming indurate on keels at maturity; winged on keels (narrowly); smooth. Fertile lemma ovate; 2–2.2 mm long; indurate; dark brown; without keel; 3 -veined. Lemma margins involute. Lemma apex acute; laterally pinched. Palea indurate.

FRUIT Caryopsis with adherent pericarp; ovoid; 1.5 mm long. Embryo 0.5 length of caryopsis. Hilum elliptic.

DISTRIBUTION South America: northern South America and Brazil.

NOTES Paniceae. WDC.

ADDITIONAL CHARACTERS Longer pedicels 4–10 times the shorter.

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