Diplachne fusca (L.) Kunth. Rev.
Gram. 1: 91 (1829).
Classification. (GPWG 2001) : Subfamily
Chloridoideae. Cynodonteae.
Basionym and/or
Replacement Name: Festuca fusca
L., Syst. Nat. (ed. 10): 2: 876 (1759).
Type of Basionym or
Protologue Information: LT: F. Hasselquist s.n., Palestine (LINN-92.21). LT designated by
Phillips, Fl. Trop. E. Afr., Gram (2): 281 (1974).
Recent synonyms:
Diplachne parviflora, D. reptatrix, Leptochloa fusca
Key references
(books and floras): [1810]. R.Brown, Prodromus (183 as Triodia
ambigua, 182 as Triodia parviflora), [1878] G.Bentham, Flora
Australiensis 7 (619 as Diplachne muelleri, Diplachne fusca, 620 as
Diplachne parviflora), [1952] C.A.Gardner, Flora of Western Australia
1 Gramineae (110 as Diplachne muelleri, 111 as Diplachne
fusca, Diplachne parviflora), [1969] E.E.Henty, Manual Grasses New
Guinea (121 as Leptochloa polystachya), [1981] M.Lazarides in J.Jessop
(ed)., Flora of Central Australia (461 as Diplachne fusca &
462 as Diplachne parviflora), [2002] D.Sharp & B.K.Simon, AusGrass,
Grasses of Australia, as Leptochloa, [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses
of South Australia (386) as Leptochloa, [2008] S.W.L.Jacobs, R.D.B.Walley &
D.J.B.Wheeler, Grasses of New South Wales (222 as Diplachne fusca, D.
parviflora, D. uninervia).
Illustrations:
[2005] K.Mallet (ed.), Flora of Australia 44B: Poaceae 3 (Fig. 79
as var. fusca), [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses
of South Australia (387, fig. 321 as
var. fusca, 388, fig. 322 as var. uninervia & 389, fig. 323
as var. muelleri), [1984] N.T.Burbidge. rev. S.W.L.Jacobs, Australian
Grasses.
Habit. Annual
or perennial. Rhizomes absent. Culms erect or geniculately ascending or
decumbent, stature slender to delicate, 25–150 cm tall. Ligule an eciliate
membrane, 1.2–8 mm long, entire or lacerate, acute. Leaf-blades flat or
conduplicate or involute or convolute, 14–55 cm long, 0.8–5 mm wide. Leaf-blade
surface scabrous.
Inflorescence.
Inflorescence compound, a panicle of racemes. Racemes 10–30, erect or
spreading, straight, 2–15 cm long. Central inflorescence axis 7–40 cm long.
Spikelets.
Spikelets pedicelled or sessile. Fertile spikelets many flowered, with at least
2 fertile florets (6–11), comprising 6–11 fertile floret(s), with diminished
florets at the apex, elliptic, laterally compressed or dorsally compressed,
5–18 mm long.
Glumes. Glumes
similar. Lower glume lanceolate, membranous, keeled, 1-keeled, 1 -nerved. Upper
glume oblong, 1.8–7.4 mm long, membranous, keeled, 1-keeled, 1 -nerved. Upper
glume apex muticous or mucronate.
Florets.
Fertile lemma 1.8–6.1 mm long, without keel or keeled, 3 -nerved. Lemma surface
indumented. Lemma apex dentate, mucronate or awned, 1 -awned. Median
(principal) awn from a sinus, 0.3–1.6 mm long overall. Palea 2 -nerved.
Lodicules present. Anthers 3. Grain 1.6–1.8 mm long.
Continental
Distribution: Africa, Temperate Asia, Tropical Asia, Australasia, and South America.
Australian
Distribution: Western Australia, Northern Territory, South Australia,
Queensland, New South Wales, Victoria, Tasmania.
Western Australia: Hall, Dampier.
Carnegie, Helms, Fortescue, Ashburton, Carnarvon, Austin. Avon.
Northern Territory: Central Australia
North, Central Australia South. South
Australia: North-western, Lake Eyre, Gairdner-Torrens Basin, Flinders
Ranges, Eastern, Murray, Yorke Peninsula, Southern Lofty. Queensland:
Burke, Cook, Darling Downs, Gregory North,
Leichhardt, Maranoa, Mitchell, Moreton, North Kennedy, Port Curtis, Warrego,
South Kennedy, Gregory South. New South Wales: North Coast, Central
Coast, Central Tablelands, North-Western Slopes, Central-Western Slopes,
South-Western Slopes, North-Western Plains, South-Western Plains, North Far
Western Plains. Victoria: Murray Mallee, Riverina, Volcanic
Plain.
Notes.
There are four subspecies, three in Australia.
Native;
all states; widespread and common in warm-temperate and tropical areas. Flowers
usually after rain.
Infra-specific
taxa: subsp. fusca, subsp. muelleri, subsp. uninervia.
1.Lowermost panicle
branches not exserted at maturity; lemma often smoky white at maturity with a
darker area surrounding the caryopsis D. fusca subsp. muelleri
Lowermost panicle branches exserted at maturity;
lemma colour various but not generally smoky white with a darker area 2
2. Lemma apex obtuse
to truncate; lemma dark green or lead coloured; anthers almost always less than
0.7 mm long D. fusca subsp. uninervia
Lemma apex obtuse to acute or acuminate; lemma
of various colours; anthers usually 0.5–2.5 mm long D. fusca subsp. fusca
