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Oplismenus burmannii (Retz.) P.Beauv.

Derivation
Oplismenus P.Beauv., Fl. Oware 2: 14 (1810); from the Greek hoplismenos (armed), alluding to the awns.

burmannii- in honour of Nicolaus Lorenz Burmann (1734–1793). Dutch botanist.

Published in
Ess. Agrostogr. 54, 168, 169 (1812).


Habit
Annual. Culms prostrate, 10–60 cm tall. Mid-culm nodes glabrous. Ligule a fringed membrane, 0.4–0.8 mm long. Collar glabrous. Leaf-blades lanceolate or ovate, 1–10 cm long, 5–20 mm wide. Leaf-blade venation with obscure cross nerves. Leaf-blade surface smooth.

Inflorescence
Inflorescence compound, a panicle of racemes. Racemes 3–8, unilateral, 0.5–2.5 cm long. Central inflorescence axis 2–13 cm long. Rhachis angular, pilose on surface. Spikelet packing imbricate or approximate.

Spikelets
Spikelets in pairs, subequal or the lower smaller. Pedicels oblong. Fertile spikelets 2-flowered, comprising 1 fertile floret, lower floret sterile, upper fertile, without rhachilla extension, lanceolate, laterally compressed, 2–3 mm long, falling entire.

Glumes
Glumes similar or dissimilar, thinner than fertile lemma. Lower glume ovate, 1.7–2.1 mm long, equalling upper glume, 50–75% of length of spikelet, herbaceous, 1-keeled, 3–5-nerved. Lower glume surface pubescent. Lower glume apex acute, awned. Lower glume awn 2.5–20 mm long, without vesture (but scaberulous). Upper glume ovate, 1.7–2.2 mm long, herbaceous, 1-keeled, 3–7-nerved. Upper glume surface pubescent. Upper glume apex obtuse, muticous or awned. Upper glume awn 0–5 mm long.

Florets
Basal sterile floret 1, with palea or without significant palea. Lemma of lower sterile floret ovate, 2.6–3.3 mm long, 100% of length of spikelet, membranous, 1-keeled, 7–11-nerved, pubescent, without hair tufts or with a transverse fringe of hairs or hair tufts, eciliate or ciliate on margins, emarginate, mucronate or awned. Fertile lemma oblong, dorsally compressed, 2–2.7 mm long, coriaceous, glossy, 7-nerved. Lemma margins involute. Lemma apex acute, laterally pinched. Palea involute, coriaceous, without keels.


Continental Distribution:
Africa, Temperate Asia, Tropical Asia, Australasia, Pacific, North America, South America.

Australian Distribution:
Northern Territory, Queensland.

Northern Territory: Darwin & Gulf. Queensland: Cook, North Kennedy.

Classification. (GPWG 2001):
Panicoideae: Paniceae

Notes
Native. A tropical species, occurring mainly in Africa and Asia. In tropical and subtropical sub-humid woodlands and coastal grasslands. In Australia, it is known from relatively few collections. Flowers Mar.–Aug. Diagnostic features include the scabrous awns.


Images
Illustrations available:
Inflorescence and detail of inflorescence (scanned specimen)
Australian distribution



Inflorescence and detail of inflorescence (scanned specimen)
© Queensland Herbarium
by Will Smith


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Australian Distribution
© ABRS


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