Setaria Ess. Agrostogr. 51, 178 (1812).

Derivation:. From Latin seta (bristle), referring to the bristly awns.

Taxonomic revisions, nomenclatural references:. R.D.Webster, Sida 16: 439–442 (1995) (Paspalidium placed in synonymy with Setaria)..

Key references (keys and floras):. G.Bentham, Flora Australiensis 7: 492–494 (1878); C.A.Gardner, Flora of Western Australia 1 Gramineae 264–268 (1952); J.W.Vickery, Flora of New South Wales, Gramineae 19: 225–241 (1975); E.E.Henty, Manual Grasses New Guinea 171–172 (1969); M.Lazarides, Tropical Grasses S.E. Asia 140–143 (1980); M.Lazarides, Flora of Central Australia 480–481 (1981); J.C.Tothill and J.B.Hacker, Grasses Southern Qld 374–376 (1983); J.P.Jessop, Flora of South Australia 4: 1976–1978 (1986); R.D.Webster, Australian Paniceae 203–216 (1987); T.D.Macfarlane, Flora of the Kimberley Region 1218–1219 (1992); B.K.Simon, Key to Australian Grasses 155–157 (1993); S.W.L.Jacobs and S.M.Hastings, Flora of New South Wales 4: 494–497 (1993); N.G.Walsh, Flora of Victoria 2: 599–601 (1994); D.I.Morris, Student's Flora of Tasmania 4B: 341–344 (1994); E.Edgar and H.E.Connor, Flora of New Zealand 5: 581–589 (2000); D.Sharp and B.K.Simon, AusGrass (2002); J.P.Jessop, Grasses of South Australia 476–486 (2006); S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th ed, 367–371 (2008).

W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (503).

Native and naturalised. About 110 species, from tropical and warm temperate regions. 16 species in Australia, WA, NT, SA, Qld, NSW, Vic, and Tas. Also New Guinea, Malesia and New Zealand.

Habit. Annual or perennial, rhizomatous or stoloniferous or tufted or decumbent. Leaf blades broad or narrow, usually not cordate, pinnately veined to palmately veined (rarely) or parallel veined. Ligule a fringed membrane (narrow) or a fringe of hairs.

Inflorescence. Inflorescence of spicate main branches or a false spike, with spikelets on contracted axes or paniculate, a spike-like panicle or an open panicle with branches ending in single spikelets, open or contracted.

Spikelets. Spikelets dorsally compressed, 2 flowered, with 1 fertile floret, with involucres of bristles or subtended by solitary bristles, several in a whorl, subsessile or pedicelled. Fertile spikelets with lower incomplete floret(s), elliptic or ovate or obovate, falling with glumes or not disarticulating (in cultivated forms).

Glumes. Glumes relatively large, unequal, shorter than adjacent lemmas or long relative to adjacent lemmas, awnless, membranous. Lower glume 3–6 nerved. Upper glume 3–9 nerved.

Florets. Lower incomplete floret(s) male, or sterile. Lemmas awnless, 5 nerved or 7 nerved (rarely), more or less equalling fertile lemmas to exceeding fertile lemmas, less firm than fertile lemmas (membranous), not becoming indurated. Fertile florets 1. Lemmas decidedly firmer than glumes, rugose, becoming indurated (crustaceous), yellow in fruit, entire at apex, pointed, muticous (usually apiculate), with a clear germination flap, 1–5 nerved, glabrous, having margins tucked into palea, usually not keeled. Palea relatively long, entire, textured like lemma, indurated, 2 nerved. Lodicules 2. Stamens 3. Grain small, ellipsoid to subglobose, compressed dorsiventrally, sculptured or smooth. Hilum short. Embryo large.

Kranz Anatomy. C4, biochemical type NADP-ME (5 species).

2n = 18, 36, 54, 63, and 72 or 36–54, 2, 4, 6, and 8 ploid, commonly adventive.

Habitat. Generally mesophytic. In woodland, grassland, weedy places. Shade species (e.g. S. palmifolia), or species of open habitats.

Classification. Panicoideae; Paniceae.

Notes. A heterogeneous genus whose traditional subdivision usefully summarise the major facies, but are of doubtful practical value due to the large number of intermediate species. The most characeristic feature is modification of the tip of the panicle branches into bristles subtending the spikelets. This is associated with contraction of the panicle along two diverging lines which lead, on the one hand to racemose branches, and on the other to a cylindrical spike (Clayton and Renvoize, 1986). Some agrostologists (Veldkamp, 1994; Webster, 1995) maintain that because there is a continuum in variation of the bristle arrangement between Paspalidium and Setaria, the generic separation is difficult to apply, and they place all species of Paspalidium under Setaria (B.K.Simon).

Types Species. S. viridis (L.) P.Beauv.

Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: Gondwanan.

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