Dichanthium sericeum

Dichanthium sericeum (R. Br.) A. Camus. Bull.
Mus. Hist. Nat. (Paris)
27: 549 (1921).

Classification. (GPWG 2001) : Subfamily
Panicoideae. Andropogoneae.

Basionym and/or
Replacement Name:
R. Br., Prodr. 201 (1810).

Type of Basionym or
Protologue Information
: LT: R. Brown 6178 [excluding part A], Australia: New South Wales:
Paterson River (BM (photo, BRI, K); ILT: BRI
(fragm. ex K), E (photo, BRI, K), K (photo, BRI)). LT designated by Blake,
Proc. Roy. Soc.
80: 67 (1969).

Recent synonyms:
D. affine.

Key references
(books and floras):
[1810]. R.Brown, Prodromus (201 as Andropogon
), [1878] G.Bentham, Flora Australiensis 7 (529 as Andropogon
530 as Andropogon affinis, Andropogon sericeus), [1952]
C.A.Gardner, Flora of Western Australia 1 Gramineae (330 as D.
, 332, 332 as D. humilius), [1969] E.E.Henty, Manual
New Guinea (69 & as D. superciliatum), [1981]
M.Lazarides in J.Jessop (ed)., Flora of Central Australia (488 as D.
sericeum, D. affine, D. humilius
), [2002] D.Sharp & B.K.Simon, AusGrass,
Grasses of Australia
, [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses
of South Australia
(516), [2008] S.W.L.Jacobs, R.D.B.Walley &
D.J.B.Wheeler, Grasses of New South Wales (207).

[1984] N.T.Burbidge. rev. S.W.L.Jacobs, Australian Grasses  (109), [2006] J.Jessop, G.R.M.Dashorst,
F.M.James, Grasses of South Australia  (517, fig. 442 & plate 20 as subsp. sericeum
& 518, fig. 443 as subsp. humilius), [2008] S.W.L.Jacobs,
R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th edn

Habit. Annual
or perennial. Culms erect, stature robust to moderate, 10–120 cm tall, 4
-noded. Mid-culm nodes bearded. Lateral branches simple or sparsely branched.
Leaf-sheaths glabrous on surface or hairy. Ligule an eciliate membrane, 0.5–1
mm long. Leaf-blades 8–15 cm long, 2–4 mm wide. Leaf-blade surface glabrous or

Inflorescence digitate, with ramose branches. Rhachis fragile at the nodes.

Spikelets sessile, 1 in the cluster. Companion spikelets pedicelled, 1 in the
cluster. Basal sterile spikelets well-developed, 2–6 in number. Companion
spikelets developed, containing empty lemmas, 3–5 mm long. Fertile spikelets
2-flowered, the lower floret barren (rarely male), the upper fertile,
comprising 1 basal sterile florets, comprising 1 fertile floret(s), without
rachilla extension, oblong, dorsally compressed, 4–4.5 mm long.

Glumes. Glumes
dissimilar, firmer than fertile lemma. Lower glume oblong, membranous or
chartaceous or indurate, much thinner above, without keels, 5–8 -nerved. Lower
glume surface indumented. Upper glume lanceolate, keeled, 1-keeled, 3 -nerved.
Upper glume surface glabrous. Upper glume apex erose. Florets. Basal
sterile florets 1, barren, without significant palea. Lemma of lower sterile
floret hyaline.

Fertile lemma without
keel, 1 -nerved. Lemma apex entire, awned, 1 -awned. Median (principal) awn
apical, 25–32 mm long overall, with a twisted column. Palea absent. Anthers 3.
Grain 1–2 mm long.

: Tropical Asia, Australasia, Pacific, and North

: Western Australia, Northern Territory, South Australia,
Queensland, New South Wales, Victoria, Tasmania.

Western Australia: Gardner,
Fitzgerald, Hall. Mueller, Giles. Northern Territory:
Darwin &
Gulf, Victoria
River. South Australia: North-western, Lake Eyre, Gairdner-Torrens
Basin, Flinders Ranges, Eastern, Northern Lofty, Southern Lofty, South-eastern.
Queensland: Burke, Burnett, Cook,
Darling Downs, Gregory North, Leichhardt, Maranoa, Mitchell, Moreton, North
Kennedy, Port Curtis, South Kennedy, Warrego, Wide Bay,
Gregory South. New South Wales: North Coast, Central Coast, Northern
Tablelands, Central Tablelands, Southern Tablelands, North-Western Slopes,
Central-Western Slopes, South-Western Slopes, North-Western Plains,
South-Western Plains, North Far Western Plains, South Far Western Plains. Victoria: Midlands,
Riverina, Volcanic Plain, Wimmera. Tasmania:
East Coast.

 Infra-specific taxa: subsp. sericeum, subsp.humilius, subsp. polystachyum.

Lower glume of pedicelled spikelet obovate with sub-apical arch conspicuous, cilia erect from surface; robust annuals     D. sericeum subsp. polystachyum        

Lower glume of pedicelled spikelet linear to narrowly ovate, cilia not erect from surface; annuals or perennials             2             

Spikelets 4.5 x 1–1.4 mm; lower glume 9–10-nerved; raceme usually more than 4 cm long; perennials                     D. sericeum subsp. sericeum

Spikelets 4 x 1 mm; lower glume 5–7-nerved; racemes less than 4 cm long; annuals                                               D. sericeum subsp. humilius

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