Leptochloa Essai Agrost. 71 (1812).
From Greek leptos (slender) and chloe (grass), referring to the
revisions, nomenclatural references:. S.T.Blake, Contr. Qld. Herb.
14:5–9 (1972); M.Lazarides, Brunonia 3: 247–269 (1980); N.Snow and
B.K.Simon, Austrobaileya 5: 299–305 (1999).
(keys and floras):. G.Bentham, Flora Australiensis 7: 616–618 (1878)
and 618–620 (as Diplachne); C.A.Gardner, Flora of Western Australia
1 Gramineae 110–111 (1952) as Diplachne and 211–212; E.E.Henty, Manual
Grasses New Guinea 121 (1969); M.Lazarides, Tropical Grasses S.E.
Asia 169–170 (as Diplachne) and 176–177(1980); M.Lazarides, Flora
of Central Australia 462(1981) and 461–462 (as Diplachne);
J.C.Tothill and J.B.Hacker, Grasses of Southern Queensland 296–297
(1983) and 202–203 (as Diplachne); J.P.Jessop, Flora of South
Australia 4: 1932–1933 (1986) as Diplachne and 1948; M.Lazarides,
F.Quinn and J.Palmer, Flora of the Kimberley Region 1151 (1992) as Diplachne
and 1185–1186; B.K.Simon, Key to Australian Grasses 104 ( asDiplachne)
and 125 (1993); S.W.L.Jacobs and K.L.McClay, Flora of New South Wales 4:
529–531 (1993) and 531–533 (as Diplachne); D.Sharp and B.K.Simon, AusGrass
(2002); K.Mallet (ed.), Flora of Australia 44B: Poaceae 3:
439–452 (2005); J.P.Jessop, Grasses of South Australia 386–390 (2006);
S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales,
4th Ed, 293–295 and 222–223 (2008) under Diplachne.
W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (337).
naturalised. 32 species, from tropical and subtropical. 9 species in Australia,
WA, NT, SA, Qld, NSW, Vic, and Tas. Also New Guinea and Malesia.
or perennial, rhizomatous or stoloniferous or tufted or decumbent. Culms woody
and persistent, or herbaceous. Leaf blades narrow. Ligule an unfringed membrane
to a fringe of hairs.
Inflorescence of spicate main branches (spiciform racemes), a spike-like
panicle or a racemose panicle with spikelets all similar, open, non-digitate
(the racemes often whorled) or subdigitate.
Spikelets laterally compressed to subterete, more than 2 flowered, with 2 or
more fertile florets, solitary, shortly pedicelled; with naked rachilla
extension. Fertile spikelets adaxial (with lower glume against rachis),
disarticulating above glumes.
unequal to more or less equal, shorter than spikelet, usually shorter than
adjacent lemmas, hairless, pointed, awnless, keeled. Lower glume 1 nerved.
Upper glume 1 nerved.
Fertile florets (1–)3–6. Lemmas less firm than glumes to similar in texture to
glumes (membranous to hyaline), not becoming indurated, entire at apex (rarely)
or incised, when entire, blunt, muticous or mucronate or awned, 3 nerved, hairy
(with appressed hairs on the lateral nerves) or glabrous, usually more or less
1 keeled. Awns when present, 1, from a sinus, non-geniculate, much shorter than
body of lemma. Palea entire to apically notched, 2 nerved. Callus short
(minute), blunt. Lodicules 2. Stamens 1–3. Grain small, compressed laterally or
compressed dorsiventrally. Hilum short. Embryo large.
C4, biochemical type PCK (L. ciliolata) or NAD-ME (L.
2n = 20,
40, and 60, 2, 4, and 6 ploid, commonly adventive.
Helophytic, mesophytic, and xerophytic. Woodland, savanna, dry and swampy soils.
Shade species and species of open habitats.
Notes. Formerly a large
and somewhat variable genus, with two sections (sect. Leptochloa and
sect. Diplachne are tolerably distinct in the Old World, but intergrade
in the New World (Clayton and Renvoize, 1986). A morphological cladistic study by Snow (1997)
shows there to be no evidence for division in the genus, but a recent study based on molecular cladistics (Peterson et al, 2012), necessitates the transfer of some species to Dinebra and recognition of four other genera Diplachne, Leptochloa, Disakisperma and Trigonochloa. All except the last occur in Australia.
Types Species. L.
virgata (L.) P.Beauv.
Element. Clifford & Simon 1981, Simon & Jacobs 1990: Gondwanan.