Brachypodium* Ess. Agrostogr. 100, 155 (1812).
Derivation:. From the Greek brachys (short) and podion (a little foot), in reference to subsessile spikelets.
Key references (keys and floras):. C.A.Gardner, Flora of Western Australia 1 Gramineae 85–86 (1952); E.E.Henty, Manual Grasses New Guinea 42 (1969); J.P.Jessop, Flora of South Australia 4:1878 (1986); B.K.Simon, Key to Australian Grasses 80 (1993); S.W.L.Jacobs and S.M.Hastings, Flora of New South Wales 4: 604 (1993); N.G.Walsh, Flora of Victoria 2: 508–509 (1994); D.I.Morris, Student's Flora of Tasmania 4B: 292–293 (1994); E.Edgar and H.E.Connor, Flora of New Zealand 5: 373–376 (2000); D.Sharp and B.K.Simon, AusGrass (2002); J.P.Jessop, Grasses of South Australia 261 (2006); S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th Ed, 171 (2008); A.Wilson (ed.), Flora of Australia 44A: Poaceae 2: 78–80 (2009).
W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (227).
Naturalised. 16 species, from temperate regions, and tropical mountains. 1 species in Australia, SA, NSW, Vic, and Tas. Also New Guinea, Malesia and New Zealand.
Habit. Annual or perennial, rhizomatous to tufted. Leaf blades broad (rarely) or narrow. Ligule an unfringed membrane.
Inflorescence. Inflorescence a single raceme or paniculate (rarely), open.
Spikelets. Spikelets all partially embedded in rachis or not all embedded, laterally compressed, more than 2 flowered, solitary, pedicelled (with broad side facing axis); with naked rachilla extension. Fertile spikelets laterally compressed, disarticulating above glumes.
Glumes. Glumes unequal to more or less equal, shorter than spikelet, shorter than adjacent lemmas, pointed, awned or awnless, similar (lanceolate). Lower glume 5–7 nerved. Upper glume 7–9 nerved or 11 nerved.
Florets. Fertile florets 8–22. Lemmas ovate-lanceolate to acuminate, similar in texture to glumes, entire at apex, pointed, awned, (5–)7–9 nerved, not keeled (rounded on the back). Awns 1, apical, non-geniculate, much shorter than body of lemma to about as long as body of lemma, persistent (3–5). Palea relatively long, entire (truncate), 2 nerved, 2 keeled. Distal incomplete florets underdeveloped. Lodicules 2. Ovary hairy. Stamens 3. Stigmas 2. Grain medium sized, longitudinally grooved, compressed dorsiventrally, with hairs confined to a terminal tuft. Hilum long-linear. Endosperm hard.
Kranz Anatomy. C3.
2n = 10, 14, 16, 18, 28, 30, 42, and 56, 2, 4, 6, and 8 ploid, commonly adventive.
Habitat. Mesophytic. Shade species, or species of open habitats.
Classification. Pooideae; Brachypodieae.
Notes. The loose raceme and elongated spikelets give Brachypodium a recognisable and fairly uniform facies. Cytology and serology point to an isolated position for Brachypodium, and it is accommodated in an independent tribe. On the other hand it intergrades morphologically with Elymus (Clayton and Renvoize, 1986).
Types Species. B. pinnatum P.Beauv.
Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: Naturalised.