Enteropogon

Enteropogon Nat. Syst. 2nd edn, . 448 (1836).

Derivation:. From Greek enteron (intestine) and pogon (beard), alluding to the awned lemmas.

Taxonomic revisions, nomenclatural references:. M.Lazarides, Austr. J. Bot. Supp.Ser. 5: 24–33 (1972); B.K.Simon, Austrobaileya 2: 1–6 (1984); S.W.L.Jacobs and J.Highet, Telopea 3: 217–222 (1988).

Key references (keys and floras):. G.Bentham, Flora Australiensis 7: 610–614 (1878) as Chloris in part; M.Lazarides, Tropical Grasses S.E.Asia 160 (1980); M.Lazarides, Flora of Central Australia 465 (1981); J.C.Tothill and J.B.Hacker, Grasses of Southern Queensland 224–225 (1983); J.P.Jessop, Flora of South Australia 4: 1953–1954 (1986); M.Lazarides, F.Quinn and J.Palmer, Flora of the Kimberley Region 1160 (1992); B.K.Simon, Key to Australian Grasses 111 (1993); S.W.L.Jacobs and J.Highet, Telopea 3: 217–222 (1988); S.W.L.Jacobs and S.M.Hastings, Flora of New South Wales 4: 520–521 (1993); N.G.Walsh, Flora of Victoria 2: 576 (1994); D.Sharp and B.K.Simon, AusGrass (2002); K.Mallet (ed.), Flora of Australia 44B: Poaceae 3: 288–294 (2005); J.P.Jessop, Grasses of South Australia 357–360 (2006); S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th ed, 242–243 (2008).

W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (396).

Native. 18 species, from Africa, Seychelles, India, Taiwan, Australia and the Pacific. 6 species in Australia, WA, NT, SA, Qld, NSW, and Vic.

Habit. Perennial, tufted. Leaf blades narrow. Ligule a fringed membrane (short).

Inflorescence. Inflorescence a single spike or of spicate main branches or a single raceme (with short pedicels), a single raceme or spike or of digitate or subdigitate racemes or spikes, digitate or subdigitate or non-digitate (when consisting of a single raceme).

Spikelets. Spikelets dorsally compressed, more than 2 flowered to 2 flowered, with 1 fertile floret, awned, solitary, sessile to subsessile (on one side of axis); with naked rachilla extension. Fertile spikelets adaxial (with lower glume against rachis), disarticulating above glumes.

Glumes. Glumes unequal, (the longer) long relative to adjacent lemmas, hairless, glabrous, awned (upper glume, often) or awnless, keeled, subulate to lanceolate, minutely bidentate, membranous, divergent. Lower glume 1 nerved. Upper glume 1 nerved.

Florets. Fertile florets 1, or 2 (the upper lemma male or with a hermaphrodite floret). Lemmas decidedly firmer than glumes (leathery or rigid, although membranous in E. dolichostachyus), entire at apex or incised, awned, 3 nerved (the median raised), glabrous or scabrous, having margins tucked into palea, not keeled. Awns 1, from a sinus or apical, non-geniculate, about as long as body of lemma to much longer than body of lemma. Palea relatively long, entire to apically notched, 2 nerved. Distal incomplete florets 1 or 2–4, underdeveloped or specialised and modified (sometimes represented by a cluster of awned rudiments). Callus short, blunt to pointed (hyaline). Lodicules 2. Stamens 3. Grain small, ellipsoid, shallowly longitudinally grooved, compressed dorsiventrally (concavo-convex). Hilum short. Embryo small to large (up to 1/3 of the grain length).

Kranz Anatomy. C4.

2n = 20, 2 ploid.

Habitat. Mesophytic to xerophytic. Savanna on sand or clay. Shade species, or species of open habitats.

Classification. Chloridoideae; Cynodonteae.

Notes. Often confused with  Chloris, but sharply differentiated by the shape of the lemma and grain (Clayton and Renvoize, 1986).

Types Species. E. monostachyos (Vahl) K.Schum. ex Engl.

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