Error message

Notice: Undefined property: stdClass::$comment_count in comment_node_page_additions() (line 728 of /var/aegir/platforms/scratchpads-2.9.4/modules/comment/comment.module).

Cymbopogon

Cymbopogon Pl. Min. Cogn. Pugil. 2: 14 (1815).

Derivation:. From Greek kumbe (boat) and pogon (beard), alluding to the boat-shaped spatheoles subtending the hairy racemes.

Taxonomic revisions, nomenclatural references:. S.T.Blake, Papers Dept. Biol. University Qld, 2(3): 55–59 (1944); S.T.Blake, Contr. Queensland Herb. 17: 29–61 (1974); S.Soenarko, Reinwardtia 9: 225–375 (1977); B.K.Simon, Austrobaileya 3: 80–82 (1989).

Key references (keys and floras):. G.Bentham, Flora Australiensis 7: 532–534(1878) as Andropogon in part; C.A.Gardner, Flora of Western Australia 1 Gramineae 337–340 (1952); J.W.Vickery, Flora of New South Wales, Gramineae 19: 51–55 (1961); E.E.Henty, Manual Grasses New Guinea 56 (1969); M.Lazarides, Tropical Grasses S.E. Asia 29–32 (1980); M.Lazarides, Flora of Central Australia 489–490(1981); J.C.Tothill and J.B.Hacker, Grasses of Southern Queensland 170–172 (1983); J.P.Jessop, Flora of South Australia 4: 1987 (1986); B.K.Simon, Flora of the Kimberley Region 1142–1143 (1992); B.K.Simon, Key to Australian Grasses 87–88 (1993); S.W.L.Jacobs and C.A.Wall, Flora of New South Wales 4: 444–445 (1993); N.G.Walsh, Flora of Victoria 2: 624–625 (1994); D.Sharp and B.K.Simon, AusGrass (2002); J.P.Jessop, Grasses of South Australia 513–514 (2006); S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th Ed, 190–191 (2008).

W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (608).

Native and naturalised. About 40 species, from tropical and subtropical Africa and Asia, Australia. 11 species in Australia, WA, NT, SA, Qld, NSW, and Vic. Also New Guinea and Malesia.

Habit. Usually perennial (rarely annual), tufted. Leaf blades broad or narrow, cordate or not cordate. Ligule an unfringed membrane to a fringed membrane.

Inflorescence. Inflorescence paniculate (leafy), a spatheathe panicle, spatheate, racemes paired or in clusters, not in tight heads, a compound pseudo-inflorescence. Spikelet-bearing axes racemes (short, spikelike, each pair with a spatheole), with heteromorphic spikelets (the pedicelled spikelets not depressed abaxially, awnless), paired (the raceme bases short to more or less connate, flattened, often widely spreading or deflexed), disarticulating at joints. Internodes densely long-hairy to somewhat hairy.

Spikelets. Spikelets laterally compressed or subterete or dorsally compressed, 2 flowered, with 1 fertile floret, unawned or awned, paired (or with a terminal triplet), sessile and pedicelled, in pedicelled/sessile combinations; sessile spikelet with lower incomplete floret. Fertile spikelets falling with glumes.

Glumes. Glumes more or less equal, long relative to adjacent lemmas, awnless, dissimilar (the lower bicarinate, the upper naviculate). Lower glume two-keeled (the keels sometimes winged apically), flattened on back to sulcate on back, relatively smooth, 1–5 nerved. Upper glume 1–5 nerved.

Florets. Lower incomplete floret(s) sterile. Lemmas awnless, 2 nerved, less firm than fertile lemmas to similar in texture to fertile lemmas, not becoming indurated (hyaline). Fertile florets 1. Lemmas hyaline to firm-stipitate beneath the awn, less firm than glumes, not becoming indurated, apically incised, muticous or awned, 1–3 nerved, glabrous. Awns when present, 1, from a sinus, geniculate, hairless (glabrous), much shorter than body of lemma to much longer than body of lemma. Palea absent. Callus short, blunt. Lodicules 2. Stamens 3. Grain small, compressed dorsiventrally (subterete to planoconvex). Hilum short. Embryo large. Pedicels free of rachis, or discernible, but fused with rachis and free of rachis (sometimes the pedicel of the homogamous pair being swollen and more or less fused with the internode). Pedicelled spikelets present, different from sessile spikelet, sterile, 1 floreted.

Kranz Anatomy. C4, biochemical type NADP-ME (C. citratus).

2n = 20, 22, 40, and 60.

Habitat. Mesophytic to xerophytic. Savanna. Species of open habitats.

Classification. Panicoideae; Andropogoneae.

Notes. A fairly homogeneous genus of narrowly circumscribed species, which are often difficult to distinguish. The concave 2-keeled sessile spikelet clearly indicates an affinity with Andropogon, from which it differs mainly in its elaborate compound panicle with deflexed raceme bases. Another distinguishing feature is the aromatic flavour when chewed, lacking in only two species (Clayton and Renvoize, 1986).

Types Species. C. schoenanthus (L.) Spreng.

Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: Old World Tropics.

AVH 2011

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith